An authentication system comprising a medium having a plurality of elements, the elements being distinctive, detectable and disposed in an irregular pattern or having an intrinsic irregularity. Each element is characterized by a determinable attribute distinct from a two-dimensional coordinate representation of simple optical absorption or simple optical reflection intensity. An attribute and position of the plurality of elements, with respect to a positional reference is detected. A processor generates an encrypted message including at least a portion of the attribute and position of the plurality of elements. The encrypted message is recorded in physical association with the medium. The elements are preferably dichroic fibers, and the attribute is preferably a polarization or dichroic axis, which may vary over the length of a fiber. An authentication of the medium based on the encrypted message may be authenticated with a statistical tolerance, based on a vector mapping of the elements of the medium, without requiring a complete image of the medium and elements to be recorded.

The issues of authentication and counterfeit deterrence can be important in many contexts. Bills of currency, stock and bond certificates, credit cards, passports, bills of lading, as well as many other legal documents (e.g., deeds, wills, etc.) All must be reliably authentic to be useful. Authentication and avoidance of counterfeiting can also be important in many less obvious contexts. For example, improved verification/counterfeiting prevention mechanisms would be very useful in, for example, verifying the contents of shipping containers, quickly identifying individuals with particular health or criminal histories, etc. Counterfeit products are, by definition, unauthorized copies of a product, its packaging, labeling, and/or its logo(s). Attractive targets for counterfeiters are items with significant brand equity or symbolic value, where the cost of production is below the market value.
In the commercial manufacturing world, it is not uncommon for counterfeit or otherwise unauthorized goods to be manufactured, distributed, and sold in direct competition with authentic goods. Counterfeiting has reached epidemic proportions worldwide, especially in the area of consumer goods including goods made from fabric, plastic, leather, metal, or combinations thereof such as clothing, handbags and wallets, perfumes, and other consumer goods. Electronics and software products are also particular targets of counterfeiters, who appropriate the value of trademarks or copyrights without license. Since costs savings based on decreased incremental cost of production (exclusive of license fees) is not a necessary element in the counterfeiting scheme, the counterfeit articles may be of apparently high quality and closely resemble authentic articles. Indeed, counterfeit articles can so closely resemble genuine goods that consumers readily confuse the counterfeit articles with the authentic articles. In other circumstances, the manufacturer segments the world market for different sales and distribution practices, so that the "counterfeit" goods may be essentially identical to authorized goods. Further, in many instances, a manufacturer produces goods under license from an intellectual property owner, and thus sales outside the terms of the license agreement are also "counterfeit".
In the U.S. alone, crime and/or fraud prevention is a multi-billion dollar market. In the commercial sector, the marking of every day products such as jeans, cosmetics and compact disk/video tapes, software, etc. can prevent the counterfeiting (bootleg) and import of fraudulent copies unauthorized by the legitimate producers.
A wide variety of attempts have been made to limit the likelihood of counterfeiting. For example, some have tried to assure the authenticity of items by putting encoded or unencoded markings thereon (e.g., an artist's signature on his or her painting). Unfortunately, as soon as the code is broken--e.g., a counterfeiter learns to duplicate a signature, this method becomes worthless for authentication purposes. In the context of paper products (e.g., currency), counterfeiting-prevention methods have also used two-dimensional authentication mechanisms--e.g., watermarks or special threads incorporated within the paper used to make the currency. These mechanisms are clearly helpful, but they can also be overcome. For example, counterfeiters routinely bleach a one-dollar bill (in such a way that the colored threads that mark the special currency paper are not damaged) and then imprint the markings of a one hundred-dollar bill thereon. Thus, the mere release of physical security materials into the market forms one limitation on their unfettered use.
Other authentication methods have utilized mechanisms that provide three dimensions of data. For example, the holograms provided on many credit cards provide more variables (i.e., relative to two-dimensional threads or watermarks) which may be precalibrated, and thereafter, used to verify the authenticity of an item. Nevertheless, since holograms have a pre-set, or deterministic, pattern they may also be duplicated and counterfeit products made. Further, since the holograms are invariant, they are subject to pilferage before application to goods, or translocation from authorized to unauthorized goods in the marketplace. Authentication mechanisms, which utilize deterministic patterns, are inherently vulnerable to counterfeiting since the counterfeiter, in essence, has a "fixed" target to shoot at. High security schemes, such as military codes, have encryption keys that change frequently. This method, however, assists prospectively in securing valuable time-sensitive information, and does not prevent subsequent decryption of a previously transmitted message. At the other end of the spectrum, a random element-based authentication mechanism would provide an incessantly "moving" and nonrepeating target that would be practically impossible to undetectably duplicate, without knowledge of the encoding scheme.
Finally, although existing authentication mechanisms provide adequate protection against counterfeiting in some contexts, increasingly powerful tools are available to decode encrypted messages, making more secure schemes necessary for long-term protection. For example, in conjunction with its monitoring and surveillance activities, governments routinely seek to break or circumvent encryption codes. The technologies employed are then quickly adopted by the private sector, and indeed government regulations seek to maintain weak encryption standards, facilitating codebreaking. In addition to computers, current counterfeiters have access to extremely powerful tools for undermining physical copy-protection schemes--e.g., color photocopying equipment, reverse engineering of semiconductor chips, etc. These factors have combined to continually provoke strong demand for new methods and mechanisms for authenticating items, especially methods and mechanisms that are less vulnerable to counterfeiting and/or employ new copy-protection mechanisms.
The security issue for a broad class of labeled consumer goods, in one sense, boils down to whether someone can mass produce a counterfeit label with a corresponding security code without being detected. At one extreme, a simple photocopy of a label would indeed work if the scanner simply looked for the location of indicia, such as two-dimensionally located fibers. The use of fluorescent fibers would require the scanner to properly illuminate the fibers to cause them to fluoresce and discriminate against a fiber that fluoresces with the wrong color. Dichroic fibers would require discrimination against fibers that differentially reflect or transmit light based on the polarization as well as color of illuminating source, and means for duplicating the pattern once detected. Clearly, the more factors that are involved the better. Thus, security features, which require specialized equipment to measure and duplicate are preferred measures.
One issue, which arises in existing technologies, is the robustness of the scheme in distinguishing authentic from counterfeit. If the authentication scheme is too strict, genuine articles will be rejected due to minor variations, such as environmental changes or exposure, deformation, or the like. On the other hand, if the authentication scheme is not strict, counterfeit goods may pass, or counterfeiters may learn to fool the authentication system into authenticating counterfeit goods on a regular basis.
PRIOR ART
ANTI-COUNTERFEITING LABEL SCHEMES
U.S. Pat. No. 5,592,561, incorporated herein by reference, suggests a system that provides an authenticating, tracking/anti-diversion, and anti-counterfeiting system that can track various goods. The system includes a control computer, a host computer, a marking system, and a field reader system, which are all compatible and can be physically linked via data transmission links. An identifiable and unique mark is placed on each good, or on materials out of which the goods are to be made, which enables subsequent inspection. The marks or patterns include areas where a marking agent is applied in an encrypted pattern and areas where it is not applied. The pattern can be scanned or captured by a reader and deciphered into encoded data. The entry can then either be compared directly to a set of authentic entries on a database or decoded and compared to a set of data on the centrally located host database. The marking system provides control over imprinting, allowing a limited number of authorized codes to be printed before reauthorization is required. In order to provide marking validation, a camera captures images of imprints. After imprinting of the encoded marking, an image of the marking is obtained and centrally authenticated as a valid code, which may be stored in a database along with stored pertinent information pertaining to this specific product. Monitoring of the marked goods is facilitated by including a unique encrypted pattern having, for example, a unique owner identifier, a unique manufacturer identifier, a unique plant identifier, a unique destination identifier, and time and date information.
U.S. Pat. Nos. 5,367,148, 5,283,422, and 4,814,589, incorporated herein by reference, provide systems for detecting counterfeit objects by employing ID codes having random number components which are stored in a database of authorized ID codes.
U.S. Pat. No. 5,367,319, incorporated herein by reference, provides a system wherein an object, such as currency, is randomly marked, such as with an ink jet printer. Counterfeiting of the object by copying is detected by sensing duplication of the random pattern.
SELF-AUTHENTICATING IMPRINTED CODES
WO 97/25177, Shachrai et al., incorporated herein by reference, relates to a gemstone marking method and apparatus, in which, in one embodiment provides an encryption code which is inscribed on the gemstone which is based, in part, on a random or irreproducible characteristic of the gemstone.
U.S. Pat. No. 5,499,924, incorporated herein by reference, relates to a digital camera with an apparatus for authentication of images produced from an image file. U.S. Pat. No. 5,351,302, incorporated herein by reference, relates to a method for authenticating objects based on a public key cryptography method encoding an ascertainable characteristic of the object, such as a serial number.
PHYSICAL SECURITY SCHEMES--OPTICAL
U.S. Pat. No. 5,574,790, incorporated herein by reference, provides a multiple-reader system for authentication of articles based on multiple sensed fluorescent discriminating variables, such as wavelengths, amplitudes, and time delays relative to a modulated illuminating light. The fluorescent indicia incorporates spatial distributions such as bar codes as discriminating features, to define a user-determined and programmable encryption of the articles' authentic identity.
U.S. Pat. No. 4,623,579, incorporated herein by reference, discloses a decorative composite article, which may be longitudinally slit to form a yarn product, which has a combined phosphorescent and fluorescent decorative appearance. The composite article includes paired outer layers of a thermoplastic resin between which is disposed a decorative layer comprising a composition including a colorant component having a phosphorescent colorant and a fluorescent colorant, and a resin binder material. The fluorescent colorant is present in an amount by weight that is up to an amount equal to that of the phosphorescent colorant. The present binder material may be selected from polyester, polyurethane and acrylic polymers and copolymers, with a mixture of butadiene-acrylonitrile rubber and polyurethane composition being preferred. The composite article is prepared by coating two resin films with the composition, followed by contacting the films with each other on their coated surfaces and applying heat and pressure to bond them together to form the decorative composite article.
U.S. Pat. No. 3,942,154, incorporated herein by reference, discloses a method and apparatus for recognizing colored patterns. The method includes encoding the colors of individual picture elements in a fabric pattern by comparing the level of transmittance or reflectance of the picture element at pre-selected wavelengths with stored values representing a reference color to generate a multibit code indicative of the color of the picture element. A comparator used for this purpose incorporates an error either proportional to the wavelength or of constant value so that the output of the comparator will indicate identity with the stored value if the input value for the picture element is within a certain range of the stored value.
U.S. Pat. No. 3,839,637, incorporated herein by reference, discloses the impregnation of spaced courses of yarn in a fabric with a material which is not visible under daylight, but which is visible only when subjected to ultra-violet light, so as to provide guide lines for cutting, or measuring indicia to enable visual counting of the number of yards of cloth in a roll from the end thereof without the necessity of unrolling the bolt.
U.S. Pat. No. 5,289,547, incorporated herein by reference, discloses a method for authenticating articles including incorporating into a carrier composition a mixture of at least two photochromic compounds that have different absorption maxima in the activated state and other different properties to form the authenticating display data on the article, subjecting the display data to various steps of the authenticating method, activation of all photochromic compounds, preferential bleaching of less than all of the photochromic compounds, and/or bleaching of all the photochromic compounds, and subsequent examination of the display data following the various activation and bleaching steps by verifying means to enable authentication.
U.S. Pat. No. 4,767,205, incorporated herein by reference, discloses an identification method and identification kit based upon making up groups of microsized particles normally visible to the naked eye with each particle in each group being of a selected uniform size, shape and color. Coded identification is established by transferring a population of particles from a selected number of the groups to the item to be identified and then confirming such identification by examining the marked item under high magnification with a light microscope.
U.S. Pat. No. 4,883,332, incorporated herein by reference, discloses a scanning fluorescent detection system.
U.S. Pat. No. 5,591,527, incorporated herein by reference, provides optical security articles and methods for making same, having layers of varying refractive index forming an image, which is viewable only across a narrow range of viewing angles and is viewable in ambient (diffuse) light, thus affording a readily apparent verification of the authenticity of the substrate.
U.S. Pat. No. 5,580,950, incorporated herein by reference, provides negative birefringent rigid rod polymer films, formed of a class of soluble polymers having a rigid rod backbone, which when used to cast films, undergo a self-orientation process aligning the polymer backbone parallel to the film surface, resulting in a film that displays negative birefringence.
U.S. Pat. No. 5,549,953, incorporated herein by reference, provides optical recording media having optically variable security properties. Thin film structures, which have an inherent color shift with viewing angle, provide both optically variable security properties and optical data decodable by optical means. The multilayer interference coating has a dielectric material, which is transparent, and a recording layer made of a light absorbing material, a crystalline-structural changing material, or a magneto-optic material. Data is encoded optically or photolithographically as bar codes or digital data.
PHYSICAL SECURITY SCHEMES--PRINTED
The use of optically variable pigments has been described in the art for a variety of applications, such as inks for counterfeit-proof applications such as currency, and generically for coating compositions. They are described, for example, in U.S. Pat. Nos. 4,434,010, 4,704,356, 4,779,898, 4,838,648, 4,930,866, 5,059,245, 5,135,812, 5,171,363, and 5,214,530, incorporated herein by reference. Pigments of these types are prepared by depositing inorganic transparent dielectric layers, semi-transparent metal layers, and metal reflecting layers onto a flexible web, and separating the layers from the web in such a manner as to fragment the deposited thin film layer structure into pigment particles. These particles are in the form of irregularly shaped flat pigment flakes. These pigments are capable of producing dramatic visual effects, including dichroic effects not observed in other types of pigments. A multilayer thin film interference structure is formed having at least one metal reflecting layer, at least one transparent dielectric layer, and at least one semi-transparent metal layer. Various combinations of these layers can be utilized to achieve the desired optically variable effect. Layer thickness can be varied according to the particular desired characteristics of the pigment. For example, U.S. Pat. No. 5,135,812, incorporated herein by reference, describes useful thickness being on the order of 80 nm for the metal reflecting layer, 5 nm for the semi-opaque metal layers, and thickness of a plurality of halfwaves of the particular design wavelength for the transparent dielectric layers.
U.S. Pat. Nos. 5,193,853, and 5,018,767, incorporated herein by reference, provide anticounterfeiting methods wherein a marked image has a minute dot or line pitch which varies from normal scanning resolution of typical copying devices, making such mechanical copying detectable.
U.S. Pat. No. 4,514,085, incorporated herein by reference, provides a method for authenticating documents by marking the document with an encapsulated liquid crystal, and then observing the document under conditions which exploit the unique optical characteristics of liquid crystals.
U.S. Pat. No. 4,507,349, incorporated herein by reference, provides a currency security system employing synthetic layers and sublimatable dye-formed images on the layers.
U.S. Pat. No. 5,601,683, incorporated herein by reference, provides a photocopy resistant document, having a background pattern or logo which is printed with solvent-sensitive, dye based ink. The presence of this photocopy-resistant background pattern or logo limits copying.
PHYSICAL SECURITY SCHEMES--ELECTROMAGNETIC
U.S. Pat. No. 5,602,381, and U.S. Pat. No. 5,601,931, incorporated herein by reference, relate to system and method for authenticating labels based on a random distribution of magnetic particles within the label and an encrypted code representing the distribution printed on the label, and possibly data imprinted on the label.
U.S. Pat. No. 3,701,165, incorporated herein by reference, discloses a method of marking garments with a substance detectable by magnetic detecting devices. When the magnetized substance on the garment part is detected in a process of making garments, subsequent garment making steps are actuated in response to the detection of the stitching.
U.S. Pat. No. 4,820,912, incorporated herein by reference, provides a method and apparatus utilizing microwaves for authenticating documents, having a random distribution of stainless steel fibers embedded and scattered in a card base member. Microwaves are applied to a large number of metallic wires which are embedded and scattered at random in a document or a card, and a proper digital mark responsive to a response microwave signature is recorded in a suitable region of the document or card according to specific rules. To check the authenticity of the document or card, microwaves are applied to the document or card, and a response microwave signature is collated with the digital mark. The document or card is determined as being authentic when the microwave signature and the mark correspond.
PHYSICAL SECURITY SCHEMES--FILMS AND EMBEDDED FILAMENTS
U.S. Pat. No. 4,157,784, incorporated herein by reference, discloses a document security system that optically reveals erasures or modifications of printed matter.
U.S. Pat. No. 3,391,479, incorporated herein by reference, discloses a card security system that provides a dichroic film covering information on the card.
U.S. Pat. No. 3,880,706, incorporated herein by reference, discloses a document security system provided by a fused polymer net within a paper pulp substrate.
U.S. Pat. No. 4,247,318, incorporated herein by reference, provides a security paper formed from non-woven polyethylene film-fibril sheets.
U.S. Pat. No. 4,186,943, incorporated herein by reference, discloses a banknote or document security system that provides an optically distinctive thin film structure in the body of the banknote or document.
U.S. Pat. No. 4,445,039, incorporated herein by reference, discloses an encoded document security system having a security element with a readable physical characteristic.
U.S. Pat. No. 4,652,015, incorporated herein by reference, discloses security paper for banknotes and currency having a metalized film having fine imprinting thereon.
U.S. Pat. No. 4,552,617, incorporated herein by reference, discloses a document security system provides dissolvable strips of microcarrier material having encoding thereon which persists after the carrier dissolves. U.S. Pat. No. 4,437,935, incorporated herein by reference, discloses a document security system provides a dissolvable carrier web material having encoding thereon which attaches to the paper fibers and persists after the web dissolves.
U.S. Pat. No. 5,393,099, incorporated herein by reference, provides an anticounterfeiting method for currency and the like having embedded micro image security features, such as holograms and diffraction gratings.
ENCRYPTION AND ENCODING SCHEMES
U.S. Pat. No. 5,426,700, incorporated herein by reference, provides a public key/private key system for verification of classes of documents, to verify the information content thereof. U.S. Pat. Nos. 5,420,924, and 5,384,846, incorporated herein by reference, provide secure identification cards bearing an image of the object to be authenticated. U.S. Pat. No. 5,388,158, incorporated herein by reference, provides a method for making a document secure against tampering or alteration.
U.S. Pat. Nos. 5,375,170, 5,263,085, and 4,405,829, incorporated herein by reference, provide encryption and digital signature schemes. U.S. Pat. Nos. 5,600,725, and 5,604,804, incorporated herein by reference, provide public key-private key encryption systems. U.S. Pat. No. 5,166,978, incorporated herein by reference, provides a microcontroller for implementing so-called RSA schemes. A so-called public key/private key encryption protocol, such as available from RSA, Redwood Calif., may be used to label the workpiece with a "digital signature". See, "A Method for Obtaining Digital Signatures and Public Key Cryptosystems" by R. L. Rivest, A. Shamir and L. Adelmann, Communications of ACM 21(2):120-126 (February 1978), expressly incorporated herein by reference. In this case, an encoding party codes the data using an appropriate algorithm, with a so-called private key. To decode the message, one must be in possession of a second code, called a public key because it may be distributed to the public and is associated with the encoding party. Upon use of this public key, the encrypted message is deciphered, and the identity of the encoding party verified. In this scheme, the encoding party need not be informed of the verification procedure. Known variations on this scheme allow private communications between parties or escrowed keys to ensure security of the data except under exceptional authentication procedures. See also, W. Diffie and M. E. Hellman, "New directions in cryptography", IEEE Trans. Information Theory, Vol. IT-22, pp. 644-654, November 1976; R. C. Merkle and M. E. Hellman, "Hiding information and signatures in trapdoor knapsacks", IEEE Trans. Information Theory, Vol. IT-24, pp. 525-530, September 1978; Fiat and Shamir, "How to prove yourself: practical solutions to identification and signature problems", Proc. Crypto 86, pp. 186-194 (August 1986); "DSS: specifications of a digital signature algorithm", National Institute of Standards and Technology, Draft, August 1991; and H. Fell and W. Diffie, "Analysis of a public key approach based on polynomial substitution", Proc. Crypto. (1985), pp. 340-349, expressly incorporated herein by reference.
Another encoding scheme uses a DES-type encryption system, which does not allow decoding of the message by the public, but only by authorized persons in possession of the codes. This therefore requires involvement of the encoding party, who decodes the message and assists in stone authentication.
U.S. Pat. Nos. 5,191,613, 5,163,091, 5,606,609, and 4,981,370, incorporated herein by reference, provide document authentication systems using electronic notary techniques. U.S. Pat. Nos. 5,142,577, 5,073,935, and 4,853,961, incorporated herein by reference, provide digital notary schemes for authenticating electronic documents.
U.S. Pat. No. 4,816,655, incorporated herein by reference, provides a document authentication scheme which employs a public key-private key scheme and which further employs unscrambled information from the document.
U.S. Pat. No. 4,637,051, incorporated herein by reference, provides a system for printing encrypted messages which are difficult to forge or alter.
U.S. Pat. No. 4,630,201, incorporated herein by reference, provides an electronic transaction verification system that employs random number values to encode transaction data.
U.S. Pat. No. 4,463,250, incorporated herein by reference, provides a method for detecting counterfeit codes based on a low density coding scheme and an authentication algorithm.
U.S. Pat. Nos. 5,464,690 and 4,913,858, incorporated herein by reference, relate to certificates having holographic security devices.
See also, U.S. Pat. Nos. 4,150,781; 4,494,381; 4,637,051; 4,864,618; 4,972,475; 4,982,437; 5,075,862; 5,142,577; 5,227,617; 5,283,422; 5,285,382; 5,337,361; 5,337,362; 5,380,047; 5,370,763; 5,243,641; 4,514,085; 4,199,615; 4,059,471; 4,178,404; 4,121,003, 5,422,954; 5,113,445; 4,893,338; 4,995,081; 4,879,747; 4,868,877; 4,853,961; 4,812,965; 4,507,744; and EP 0,328,320, incorporated herein by reference.
Thus, there remains a need for a system and method for controlling, enabling, and directing marking of goods during the manufacturing process and enabling detection/cross-validation of the marks so that the goods are uniquely identified and tracked throughout the stream of commerce. In addition, there remains a need for a method and system for marking such that the markings are not readily reproducible with commonly available devices and so that the markings contain sufficient information for product authentication, identification, and tracking. There also remains a need for an article marking method wherein the marking is particularized for the individual article and therefore preventing an otherwise authentic label from being placed on a different article, and preventing forgery of the label or the associated object.
There further exists a need for improved systems and methods which provide security features for labeling and anticounterfeiting schemes, providing physical security, which is applicable to mass market consumer goods, i.e., a system which is low cost, easy to apply, have secure hardware designs, and are easily authenticated by both physical security and identification codes. Heretofore, such systems have had various shortcomings.

System and method for authentication of goods


This invention aims to provide a recycled magnesium alloy having a good corrosion resistance and a process for producing the same. The process of the present invention comprises an adjusting step of adjusting composition of molten metal of a magnesium alloy so as to comprise, by mass: Al: 5 to 10%, Zn: not less than 1% and not less than three times of Cu content (%), Mn: 0.1 to 1.5% and the remainder: Mg and impurities with or without one or more reforming elements. While the upper limit of the Al content is restricted to a low level, the Zn content is increased in accordance with the Cu content. Therefore, the recycled magnesium alloy produced by this process can effectively suppress corrosion caused by Cu, which is one of corrosion-causing elements.

Magnesium (Mg) is the lightest of the practical metals and has a good specific strength, and its resources are abundant. Now that weight saving and reduction of environmental burdens are strongly demanded, magnesium is a promising metal material and magnesium alloys are becoming to be used in various products in various fields.
Magnesium, however, is a very active metal and has the lowest potential (i.e., the highest ionization tendency) among the practical metals. Since magnesium does not form a corrosion resistant film on itself, magnesium-based members are susceptible to corrosion. Therefore, acquisition of corrosion resistance is essential to widespread utilization of the magnesium-based members. One possible means for the acquisition is to provide a corrosion resistant film on a surface of the magnesium-based members. However, formation of a corrosion resistant film incurs high costs. Moreover, even if a corrosion resistant film is formed, corrosion may proceed from defect portions or damaged portions of the film.
Therefore, there is a need for magnesium alloys having good corrosion resistance in themselves. The root cause of corrosion of magnesium alloys is the presence of impurity elements (corrosion-causing elements) such as copper (Cu), iron (Fe) and nickel (Ni). Accordingly, conventional magnesium alloys ensure corrosion resistance by strictly limiting the amount of these corrosion-causing elements mixed in the alloys. For example, a known alloy AZ91D according to ASTM standards ensures good corrosion resistance by strictly limiting the content of corrosion-causing impurities to less than 0.03 mass % (300 ppm) of Cu, less than 0.0015 mass % (15 ppm) of Ni, and less than 0.005 mass % (50 ppm) of Fe. Such a magnesium alloy needs to be produced under strictly controlled conditions and production of brand-new products is taken for granted. This not only incurs an increase in production costs but also inhibits recyclability of magnesium-based members, and does not meet current demand for effective utilization of resources and reduction of environmental burdens.

Recycled magnesium alloy, process for producing the same, and magnesium alloy


This invention relates to splints and the method of manufacturing these splints for first aid or emergency rescue use, and has particular reference to an improved hinge and pivot splint having angular adjustment and securing devices.

1. Field of the Invention
This invention relates generally to splints for first aid or emergency rescue use, and has particular reference to an improved hinge and pivot splint having angular adjustment and securing means.
2. Description of the Prior Art
There have been hinge and pivot splints developed in the past, however most are for surgical use, used only on a single body part, and require professional experience to apply to a patient.
In the prehospital setting it is particularly important to splint the injured body part, whether it be the knee, arm, shoulder, ankle or back, in the exact position in which it is found. Should the body part position be changed there is the danger that both the blood vessels and the nerves within and surrounding the injured body part will be damaged.
In the past, splints for emergency use have consisted of two side pieces placed on both sides of a limb. The side pieces are braced together and the desired angle is set by means of a screw.
A more recent development has been the use of a set of splints for both leg and arm injuries. U.S. Pat. No. 2,339,515 discloses the use of two dissimilar contoured sections, one having a crutch-type end portion, clamped together through the means of a bolt. The splint sections can be fixed in alignment or at relative angles up to 90.degree.. In order for the splint to be used on both the leg and the arm, a more comprehensive set of splint sections with increased lengths are necessary.
In other recent developments, splint devices include members which are angularly as well as linearly adjustable. These splints have limited orientation settings. It is also necessary to bolt the planar members together through individual or continuous slots. The securement of the members in a particular position is cumbersome, time consuming and may require personnel specifically trained in those mechanisms. In addition, these devices are not easily adjustable.
Additional operating problems arise with the use of the conventional splint. The paramedic or other emergency worker must carry additional instruments needed to construct the splint, i.e., additional pieces to lengthen the splint for it to conform to different parts of the body, the necessary nuts and bolts to adjust and tighten the particular angle, and a tool for the actual tightening of the bolts. Additional storage space is also needed. There is also the danger that the pieces may be lost, or not within the immediate vicinity when needed. In addition, it is difficult for one person to both adjust the angle needed, and maintain the angle while tightening the bolts.
It is therefore an object of the present invention to provide an improved splint for the immobilization of straight and non-straight skeletal injuries in the prehospital emergency setting.
It is another object of the present invention to provide a splint for use with all body parts.
It is yet another object of the present invention to provide a splint which offers vastly improved stabilization while minimizing injury manipulation and maximizing patient comfort.
It is yet another object of the present invention to provide a splint which can be adjusted, applied, and secured in a minimum amount of time by a single person.
It is a further object of the present invention to provide a splint which can be simply constructed, readily accessible, and easily stored.
It is still a further object of the present invention to provide a splint which allows an operating range of nearly 270 degrees.


A dynamometer link comprises a first transmission member adapted to slide axially relative to a second transmission member with spring means disposed between the first and second transmission members. Relative displacement of the two members is amplified by a lever pivotally mounted on one of the two members and on which the other member operates. The lever comprises at least a radial arm articulated to one of the members and comprising at a distance from the articulation a two-way axial coupling to the other member and an axial arm having a free end on respective sides of which are disposed two detector members. The link is able to determine the direction of the force transmitted by the link.

1. Field of the invention
The present invention concerns a dynamometer link, that is to say a link adapted to provide information relating to the magnitude of forces that it transmits along a longitudinal axis.
2. Description of the prior art
French patent 2 434 377 discloses a link of this kind comprising at least two male and female members disposed to slide axially one within the other and spring-loaded by respective spring means so that a force transmitted by the link causes a relative displacement representing said force. This relative movement is detected by a lever pivoting inside the female member one end of which cooperates with a cam carried by the male member and the other end of which is adapted to operate a microswitch when the relative displacement of the two members and therefore the pivoting of the lever exceeds a particular threshold.
Of course, to avoid any disturbance of the kinematic system in which the link is incorporated, the relative displacement of the two members must be as small as possible and must preferably lie outside the range of normal loads on the link.
To this end the prior art patent provides for:
prestressing the spring means so that relative displacement of the two members occurs only beyond a predetermined force threshold; PA0 dimensioning the lever and disposing the microswitch so that the latter is operated only beyond a second force threshold higher than the first.
The solutions put forward in this prior art patent have two drawbacks.
The first is that the cam-abutment-lever system is relatively bulky and requires relatively high amplification of the relative movement detected and consequently a long lever. The female member of the link which contains this system must therefore be relatively long and bulky. The use of two levers, one of which carries the microswitch, makes it possible to reduce the length of this member by half. However, this reduction in the length is achieved at the cost of an increase in the diameter.
The second drawback is that this device cannot determine the direction of the force transmitted by the link. This information is relatively important because it makes it possible to distinguish a driving force from a force due to an external force applied to the load.
A particular object of the invention is to eliminate these drawbacks.


An audio speaker cover with a central region and a peripheral region. The central region has a surface that faces an observer and a speaker cover body below the surface. The audio speaker cover body defines a plurality of apertures with lands between the apertures. The apertures have cylindrical walls that meet the surface orthogonally. Precisely engineered apertures permit minimal sound transmission loss and allow a high aperture density without sacrificing the ability of intervening lands in the audio speaker cover to protect an underlying speaker.

Audio speaker covers have been manufactured for decades from a variety of materials including fabric, thermoplastics, thermosets, perforated metal, expanded metal, woven wire, and the like. Certain materials such as fabric may be thin and have a large open area percentage. This may be ideal for sound transmission. But these materials lack the ability to adequately protect the speaker assembly in environments where human contact and abuse is anticipated. Examples include home audio systems, electronic devices, computers, microphones, portable speakers, and transportation-related audio systems such as cars, trucks, boats, aircraft and the like.
In such applications, substantially rigid audio covers are deployed adjacent to the speaker itself to protect the fragile speaker cone and assembly from damage. Additionally, since these systems are in proximity to the audiophile, visual styling and aesthetics are also necessary in order to produce a cost-effective yet attractive means of protecting the speaker itself.
Speaker covers may be injection molded from thermoplastics. However, plastics have a lower strength to weight ratio compared to metal speaker covers and therefore require substantially more thickness than a metal cover to protect the speaker assembly. In order to mold the cover, a minimum of 0.5 degrees of draft must be added to the design of the molded hole in order to "demold" the cover without sticking to the mold and deforming the cover upon ejection from the mold. This draft condition may be from one direction as pictured in FIG. 1 or at a mid-plane between mold halves.
Metal speaker covers have historically offered superior sound transmission characteristics compared to plastic speaker covers due to their high strength to weight ratio. Metal audio covers can be produced from a variety of metals including woven metal wire and with sheets of metal which are subject to a variety of processes to create apertures for sound transmission. These sheet-based processes include metal expanding, punch perforating, laser cutting, water jet cutting, photochemical etching, and powdered metal laser sintering. Sheets of these materials with apertures are then converted in finished goods using traditional metal forming techniques combined with a variety of coating and finishing techniques. However, the finished speaker cover needs to be visually pleasing to the audiophile. The penalty for adding a cover is always the amount of sound transmission loss due to solid or the non-open area of the rigid speaker cover that protects the speaker.
The ideal speaker cover is both attractive and cost effective to manufacture along with providing adequate strength that withstands normal abuse and offers the lowest possible sound transmission loss. Metal speaker covers have traditionally offered the best balance of strength and lower levels of sound transmission loss than compared to injection molded speaker covers.
Current methods for making apertures in metal speaker covers generally fail to balance aesthetics, strength, and acoustic performance. Each technology lacks an essential element in that it creates apertures which are less than ideal for minimizing sound transmission loss while maintaining the strength to adequately protect the speaker from abuse. Known manufacturing techniques in the art of making speaker grills include use of woven wire, metal expanding, metal perforating, laser cutting, water jet cutting, photochemical etching and powdered metal sintering.
Woven wire is created by weaving individual strands of wire to create a wire mesh, much like the way cloth is woven to create fabrics. FIG. 2 is an image of a typical wire mesh. However, the material is expensive since wire must be manufactured and then woven into a mesh with ends that are prone to separation. Furthermore, the material has irregular apertures that are not ideal for acoustic performance.
Metal expanding techniques cost effectively produce apertures in rows by shearing and tearing the metal to create the apertures. FIG. 3 is an image of expanded metal. However, the expanding process often results in hardening and embrittlement of the metal which leaves the material susceptible to tearing. The hardening that occurs makes the material challenging to form complex shapes. Furthermore, the walls of the resulting apertures are rough and not parallel to one another and are therefore not ideal for sound transmission. However, this does produce an attractive surface with reasonable economics and acceptable acoustic performance.
Metal perforating using traditional stamping techniques is often used to produce an array of apertures in a sheet of metal. FIGS. 4A-4B are views of a "punched" aperture. As depicted, there is an initial deformation that occurs on the surface contacted by the punch. The walls that result from the punching operation are not parallel to one another. They have a rough surface that is "torn". The punch compresses a "slug" of material through the button which generates wasted material. The tapered aperture that results from this manufacturing process is not ideal for sound transmission. While a punched side surface may be aesthetically satisfactory, the slug exit usually has an unsightly burr which is generally hidden from view and is typically oriented toward the speaker assembly.
Laser cutting is also used to create apertures in metal speaker covers. Fiber or CO2 lasers can effectively burn and melt through the sheet metal to produce apertures. However, this process yields unsightly apertures, as shown in the FIGS. 5A-5B. The resulting walls of the aperture are irregular, and they are not parallel to one another. This condition is not desirable for acoustic performance. Furthermore, metal splatter is generated as the laser bursts through the material. Like punched metal, this melted metal splattered surface is typically hidden from the consumer, like the burr side of perforated or punched speaker covers.
Water jet cutting produces a tapered cut, like laser cutting without the metal splatter. Again, a tapered irregular wall results from the process, which is not ideal for strength and acoustic performance. To illustrate, FIG. 6 is a series of progressive sections of water jet cutting apertures through a material. Thus, water jet cutting is only suitable for producing large apertures with non-parallel walls. They are generally unsuitable, both visually and economically for audio covers.
Photochemical etching can also be used to produce apertures within a metal sheet. A resist layer is applied to a surface. Then that layer is selectively removed in areas where the apertures are required. FIG. 7 is a sectional view of a layer of sheet metal and a pre-applied resist layer before and after etching. The resist protects the metal surface not exposed to the etchant which "eats" into the metal. Resist and etchant may be applied to one or both sides of the metal. The etchant begins etching into unmasked surface as well beneath the area where the resist remains as depicted in FIG. 8. This method also produces walls which are both irregular and not parallel to one another, which is not ideal for acoustical performance.
Powdered metal sintering can produce a speaker cover with apertures whose walls are relatively parallel to one another. However, the resulting aperture walls and surface texture is poor and require secondary refinishing prior to the final surface treatment. The surface that results is not suitable for "Class A" applications. Furthermore, this method has proven to be cost prohibitive for most applications and is only suitable for rough proof of concept prototypes at this time.

Audio speaker cover for enhanced audio performance


A system for transporting downstream and upstream traffic between service providers and end user terminals is provided. The system may include an apparatus having multiple egress ports configured for transmitting downstream traffic received from the service providers towards nodes adapted for replicating the traffic, at one network layer, and further transmitting the replicated traffic toward the end user terminals. The system may further include a merging unit coupled to ingress port of another apparatus receiving upstream traffic from the user end terminals, where the merging unit is adapted for merging the upstream traffic, at a different network layer, according to which service provider the upstream traffic received from the end user terminals is intended to and for transmitting the merged traffic toward the service providers.

As networks continue to evolve, many network operators are deploying infrastructure for supporting both Internet Protocol (IP) television (TV) service and Internet access service. In general, a network supporting both IP TV and Internet access requires a unidirectional connection for broadcasting IP TV data from an IP TV service provider to a DSLAM serving the associated end users, and a bidirectional connection from the DSLAM serving the end user to the IP point-of-presence (POP) for the Internet access service. Alternatively, rather than a bidirectional connection for the Internet access service, the Internet access service may be provided using a multicast connection which provides both the IP TV service and the Internet access service.
In such a configuration, the network includes one multicast connection from each service provider to the DSLAMs and one unicast connection from each DSLAM to each service provider. In other words, the network must support multicast connectivity from the service providers to the DSLAMs and unicast connectivity from DSLAMs to the service providers. In existing configurations, an Ethernet network is used for interconnecting the service providers and the DSLAMS which serve the associated end users.
In one configuration, an Ethernet switch interconnects the service providers and the DSLAMS such that there is a bidirectional connection between each service provider and the Ethernet switch and a bidirectional connection between the Ethernet switch and each DSLAM for each service provider. In such a configuration, different service providers may share a connection using an Ethernet-based virtual local area network (VLAN). Disadvantageously, this configuration requires replication of the multicast IP TV service traffic at the Ethernet switch, thereby resulting in network bandwidth inefficiency when replicated Ethernet frames follow the same path through the network.
In another configuration, Ethernet frame replication may be performed further downstream by deploying additional Ethernet switches between the Ethernet switch associated with the service providers and the DSLAMs associated with the end users, thereby eliminating network bandwidth inefficiency. Disadvantageously, however, this configuration requires additional Ethernet switching capacity and may require use of the Spanning Tree Protocol for protection. In one such configuration, the additional Ethernet switches may be deployed for aggregating the traffic of the DSLAMs (i.e., a hub-and-spoke configuration in which the hub Ethernet switch is directly connected to the service providers and the spoke Ethernet switches are directly connected to the DSLAMs). Although this configuration does not require use of Spanning Tree Protocol, disadvantageously, this configuration does not eliminate the bandwidth inefficiency.

Apparatus for providing internet protocol television service and internet service


A method and apparatus for transmitting encoded data from one computer system to another using an AT command set compatible communication device is described. Data being sent from a communications application to the AT command set compatible communication device is monitored, and encryption is performed in response to detecting a connect message and a carrier detect signal received from the communication device and changing in response to said detection the state of an encryption application from a first state to a remote state and the data is encrypted using a stream encryption scheme before it is passed to the communication device. When a break sequence is detected or a carrier detect signal is deasserted, encryption is ceased thus having the encryption application automatically return to the first state.

1. Field of the Invention
The described invention relates generally to the field of data communications. More particularly, the invention relates to a method and apparatus for encrypting data that can be used with standard software communication applications using modems.
2. Prior Art
The use of a modem in combination with a standard telephone line is a common method for exchanging data between computer systems. Modems use a standard communication interface that allows modems from different manufacturers to communicate with each other. The "Advanced Technology" command set has also become a defacto standard command language with which computer systems can control a modem. This combination of a standard command language and a standard interface allows modems made by different manufacturers to provide communication capability with computer systems which are also from different manufacturers. This compatibility gives a user the ability to purchase computers and modems based on price and quality considerations only, and therefore is desirable.
Most recently, modems have been developed which operate over cellular networks using standard cellular phones. In addition, AT compatible modems have been developed that operate over the radio network.
The use of a modem with a highly compatible interface creates some security risk, however, because anyone able to detect the signals used by the modems to exchange information can determine the contents of that information. In the past, this security risk has been minimized by the relatively high degree of privacy offered by a standard phone line. The use of cellular telephones as a substitute for traditional telephones, however, has removed this at least somewhat satisfactory degree of security because the signals carrying the information being exchanged are broadcast where they can be detected by anyone so inclined. Thus, the use of a cellular telephone for data communication between computer systems has created the need to make the information transmitted by the cellular telephone unreadable to anyone other than the intended recipient.
The growing presence of mobile computing involving portable computers and wireless data communications poses a considerable threat to corporate security since wireless communications are vulnerable to interceptions. The communications software used with these portables relies on simple passwords to protect access to the network and the login script generally holds the password in plain text. In other words, the stolen portables gives the thief an easy access to the network. Even some applications that use encryption do not employ a strong encryption scheme.
Encryption provides one method for making the information transmitted by modems unreadable to anyone other than the intended recipient. While modems that provide encryption capability exist, the encryption feature cannot be utilized unless the receiving modem also possesses the same encryption capability. This requirement eliminates much of the desired compatibility previously offered by modems that did not posses encryption capability. Additionally, this hardware-based solution adds to the cost of the modem. Alternatively, communication software programs may incorporate an encryption feature, however, this requires the two computer systems communicating with each other to utilize communication software applications that incorporate the same encryption method. Once again, this reduces users choices and eliminates the previously established compatibility among computer systems. Thus, it is desirable to have a method and apparatus of encrypting data that allows various standard computer systems, software applications, and modems to be used interchangeably and which can be uniformly applied with modems that operate over cellular networks, radio networks and regular telephone lines.

Modem compatible method and apparatus for encrypting data that is transparent to software applications


A lamp driving system controlled by electrical isolating is provided. The front-end power stage and the back-end power stage of the lamp driving system are electrically isolated each other by an electrical isolator. The lamp driving system includes a PFC controller for outputting a high voltage into a switching circuit. The switching circuit outputs a lamp driving voltage into the primary side of a boost transformer. A loading resonant network couples to the secondary side of the boost transformer, and generates a feedback signal. There are having the primary side of the electrical isolator, the PFC controller, the switching circuit and boost transformer coupled to a primary ground end. The PFC controller, the loading resonant network and the secondary side of the electrical isolator are coupled to a secondary ground end.

1. Field of the Invention
The present invention relates to a lamp driving system controlled by electrical isolation, and more particularly to a lamp driving system that uses an electrical isolator to control the signal isolation.
2. Description of Related Art
According to the IEC1000-3-2 international specification, a power supply having an input power over 75W needs to have a power factor correction (PFC) function, and thus a front-end power stage of a power supply generally includes a power factor correction controller. The power factor correction controller is a prior art that performs a power factor correction to an AC power while reducing the harmonic current in the power supply and producing an output of a constant voltage approximately equal to 400V.
Referring to FIG. 1 for a schematic circuit block diagram of a lamp driving system in accordance with a prior art, the lamp driving system 1 includes a power factor correction controller 10, an isolating DC/DC converter 12, a switching circuit 14, a PWM controller 16, a boost transformer 18, a loading resonant network 19, a voltage regulator 13 and a system controller 15.
A front-end power stage of the prior art lamp driving system 1 includes a power factor correction controller 10 and an isolating DC/DC converter 12. The power factor correction controller 10 receives an alternate current power AC and produces an output of a constant high voltage HV. The isolating DC/DC converter 12 converts a constant high voltage isolation into the output of a repeated voltage VCC for the back-end power stage of a prior art lamp driving system 1. The back-end power stage includes a switching circuit 14, a PWM controller 16, a boost transformer 18 and a loading resonant network 19. The prior art lamp driving system 1 uses a voltage regulator 13 to convert AC power into outputs of voltage in various different specifications, and the output voltage is provided for a system controller 15, a PWM controller 16, or other circuits.
When the prior art lamp driving system 1 is lit, the system controller 15 will output a start control signal ST to notice the PWM controller 16 to start lighting up the lamp, and the PWM controller 16 will produce a control signal SPWM to control the switch of the switching circuit 14. The switching circuit 14 switches the repeated voltage VCC to output a high-frequency switching power to the boost transformer 18, and the boost transformer 18 will boost the high-frequency switching power to a high-voltage switching power output for the loading resonant network 19. The PWM controller 16 will obtain a feedback signal SFB from the loading resonant network 19, and adjust the output of the control signal SPWM according to the feedback signal SFB to maintain the stability of the lamp driving system 1.
In a traditional lamp driving system 1, the front-end power stage requires a power factor correction controller 10 to improve the power factor, lower the harmonic current and produce a constant voltage, but the constant high voltage produced by the power factor correction controller 10 will affect the operations of the back-end PWM controller 16, the system controller 15 or other controllers. Therefore, the traditional lamp driving system 1 needs to use an isolating DC/DC converter 12 in the front-end power stage for the electrical isolation and voltage step-down, so as to assure the normal operation of the circuit in the back-end power stage.
In general, the isolating DC/DC converter 12 includes components such as a transformer, a controller, a switching circuit and a feedback network, and thus the isolating DC/DC converter 12 of a traditional lamp driving system 1 has a much higher price than other components, and the isolating DC/DC converter 12 occupies quite a large volume in the overall component layout of the lamp driving system 1.
With the consideration of the overall price and component layout of the lamp driving system, it is an important subject for manufacturers to waive the use of an isolating DC/DC converter 12 in a lamp driving system that requires a power factor correction controller to improve the power factor by providing a back-end power stage electrically isolated lamp driving system.

Lamp driving system controlled by electrical isolation

Lien Chang Electronic Enterprise Co., Ltd.


Acoustic signals received by the ears are controlled by feeding back and filtering the signal to be applied to the speaker, rather than by use of a feedforward filter. The feedback filter may incorporate an electrical model of the speaker-to-ear transfer function to force the ear signals to a desired ratio of amplitudes and phases as a function of the frequency. The signals to be output to the right and left channels are fed back through a filter to obtain a feedback signal. The feedback signal is subtracted from one input channel and added to the other input channel to provide the output signals. This technique may be used both in stereo spreading and in three-dimensional localization of a monaural sound source. By using feedback instead of feedforward, the system can be readily adapted to different playback environments. Through a simple adjustment of the electrical model of the speaker-to-ear transfer functions, this system automatically provides the desired ear signals. Since the adjustment simply changes a model, it is possible dynamically to adapt the model to suit the position of the listener. For a simple low-cost stereo spreading system, the filter can be a simple feedback system where several transfer functions are reduced to a single filter.

There are generally two classes of three-dimensional sound manipulation. The first class of manipulation involves processing of conventional recordings to create a wider sense of spaciousness, with sounds apparently emanating from beyond the position of the loud speakers. Such systems include the "SRS system," described in U.S. Pat. Nos. 4,748,669, 4,841,592 and 4,886,774, assigned to Hughes Aircraft Company, the "spatializer" products marketed by Desper Products, such as described in U.S. Pat. No. 4,308,423 (to Joel Cohen) and U.S. Pat. No. 5,412,731 (assigned to Desper Products, Inc.), the QSound System, described in U.S. Pat. Nos. 5,026,051, 5,046,097, 5,052,685, 5,105,462, 5,208,860, 5,371,799 and 5,436,975 (assigned to QSound Ltd.), and a system described by Robert W. Carver in U.S. Pat. Nos. 4,603,429 and 4,309,570. The techniques used in these systems are commonly referred to as "stereo spreading."
The second class of sound manipulation involves the arbitrary placement of single or multiple mono sound sources. This allows a computer to dynamically change the apparent location of sound. This technique involves more exact modeling of the human ear system, and in general requires a digital signal processor to implement localization filters.
The techniques of the first class of three-dimensional sound manipulation generally use a form of feedforward signal processing. For example, in the system described by Carver, an anti-phase electrical cross-coupling signal is introduced to eliminate cross-coupling between right channel signals which reach the left ear and left channel signals which reach the right ear. The anti-phase signal is designed to match the ratio of the transfer function from the speaker to the near ear to the transfer function from the speaker to the far ear. This introduction of an anti-phase electrical cross-coupling signal typically involves a delay of about two hundred microseconds and a frequency response roll off above one kilohertz. By canceling the cross-coupling paths, a signal that comes from the right speaker appears to be farther to the right only because the sound at the left ear is reduced in amplitude. There are several drawbacks to this technique. One is that room acoustics prevent effective cancellation because the sound arriving at the opposite ear is composed not only of sounds traveling along the path from the speaker to the opposite ear, but also includes sound reflected from walls or other objects in the room. Another drawback is that the electrical frequency response of a system using cross-cancellation is not flat, and this causes a sound reproduction to sound hollow.
In the "spatializer" system, rather than using cross-cancellation, a difference signal is derived by subtracting the right input from the left input. This difference signal is fed forward through a signal processing block consisting of a delay and low pass filter. The output of this filter is added to one channel and subtracted from the other channel. For monaural signals, the difference signal component is zero; therefore no processing takes place. Since most of the bass and lead vocal signals are panned to the center, frequency response aberrations which may occur in the Carver system generally do not occur in the "spatializer" system. For signals that appear in the left or right channels only, however, the frequency response is affected. This system works by shifting the phase of low frequencies between the ears. Since the primary localization mechanism below 0.5 kilohertz is inter-aural phase, images outside of the speakers can be obtained by increasing this phase shift. A drawback of this system is that it is optimized by trial-and-error selection of filter components. While it is easy to derive the ear response for a particular set of filter components, it is more difficult to start with the specification of the desired ear response and to derive the required filter components.

Electronic circuit and process for creation of three-dimensional audio effects and corresponding sound recording


In a vehicle navigation apparatus, displaying an enlarged view of an intersection within a guide route is suppressed when a value N associated with a corresponding passing direction of the intersection exceeds a learning reference value. When the value N is not more than the learning reference value, the enlarged view of the intersection is displayed on a display unit. When a deletion operation is received while the enlarged view is displayed, the value N is incremented by “1.” In contrast, when an enlarged view display operation is received while the enlarged view is not displayed, the value N is decremented by “1.”

Conventionally, there is known a navigation apparatus which displays an enlarged view of an intersection on a display unit. That is, when the vehicle comes to a position before the intersection in a navigation route, the navigation apparatus displays an enlarged view of the intersection by enlarging the intersection from a map that has been displayed on the display unit.
However, regarding an intersection through which the vehicle has frequently passed, it is unnecessary for a user to display an enlarged view of the intersection. Further, upon displaying of the enlarged view of the intersection, some portions (e.g., a map around the intersection, traffic congestion information, and construction information) are covered with the enlarged view. Occasionally such information may be more important for the user.
To handle such cases, for example, regarding an intersection, through which the vehicle has passed many times, displaying the enlarged view of the intersection may be suppressed. However, even regarding an intersection through which the vehicle has passed many times, the user may sometimes need the display of the enlarged view of the intersection. Otherwise, the user does not need an enlarged view any more regarding an intersection through which the vehicle has passed several times. Furthermore, whether a user requests such frequent guidance is depending on user's preference, age, and the like.


The implementation of two-dimensional decoding, necessary to achieve a reasonable array aspect ratio for a large content addressable memory, is achieved by having multiple match lines per physical row, these match lines being physically routed on top of the array core cell in an upper metal layer. To limit power dissipation in the resulting large-capacity content addressable memory, the match function is implemented by two or more NAND chains per word. Means for achieving the precharging and evaluation of these chains, and for implementing dummy chains for the provision of timing information, are also disclosed.

CAMs are memories in which data is selected based on its contents, rather than its physical location. This function is useful for many applications, especially when performing a look-up for the purposes of mapping from a long identification word to a shorter word. This operation is required in many telecom functions, including Asynchronous Transfer Mode (ATM) address translation.
U.S. Pat. No. 5,289,403 entitled "Self-Timed Content Addressable Memory Access Mechanism with Built-In Margin Test Feature" granted to J. D. Yetter on Feb. 22, 1994 describes a means of providing self-timing to a NOR-match line CAM, using a dummy column and dummy row. The bit at the intersection of the dummy column and dummy row always misses, while all other cells in that row always match, and this generates the slowest possible mismatch condition on the dummy match line. This signal is then used to generate a clock for timing of subsequent events, and for qualifying all other match lines.
U.S. Pat. No. 5,453,948 entitled "Associative Memory" granted to M. Yoneda on Sep. 26, 1995 describes a low-power implementation of a match line, in which the match line is realized as a series chain, instead of a NOR.
U.S. Pat. No. 5,455,784 entitled "Associative Memory Device with Small Memory Cells Selectively Storing Data Bits and Don't Care Bits" granted to H. Yamada on Oct. 3, 1995 describes a CAM with individual storage cells comprised of a series combination of two EEPROM devices. The series connection of these cells (one per bit) to form a word of CAM results in a series match line chain. Shifted transistor threshold voltages, resulting from programming, cause the EEPROM devices to act as either enhancement- or depletion-mode transistors, and hence "don't cares" may be stored by making both devices depletion-mode.
U.S. Pat. No. 5,469,378 entitled "Content Addressable Memory Having Match Line Transistors Connected in Series and Coupled to Current Sensing Circuit" granted to R. Albon et al on Nov. 21, 1995 describes a series match line chain.
Most previous CAMs employ a dynamic wired-NOR match line pull-down, which provides high speed. However, the prior art circuit construction causes match lines associated with mismatched words to experience transitions, while no transitions occur on match lines associated with matched words. Since the number of matches is much smaller than the number of mismatches, the number of transitions, and hence the power dissipation, is excessive for a wired-NOR match line CAM.


A method for creating digital documents from hardcopy documents by means of a reproduction system including a display and a scanner includes detecting an event of an intended scanning of a hardcopy document; upon detection of the event, opening an image adjustment screen at the display, the screen including an image area, a scan settings area and a process button; displaying at the image area of the screen a digital image; displaying, at the scan settings area of the screen, image parameter values; activating the image parameter values by activating the process button; closing the screen at the display; scanning the hardcopy document according to the image parameter values corresponding with the displayed digital image resulting in a digital document; and selecting the digital image to be displayed to be either equal to a digital image that has been previously stored, or equal to a predetermined other digital image.

1. Field of the Invention
The present invention relates to a method for creating digital documents from hardcopy documents by means of a reproduction system comprising a display and a scanner, wherein the method comprises the steps of: detecting an event of an intended scanning of a hardcopy document; upon detection of the event, opening an image adjustment screen at the display, said image adjustment screen comprising an image area, a scan settings area and a process button; before scanning of the hardcopy document, displaying a digital image at the image area of the image adjustment screen; displaying image parameter values at the scan settings area of the image adjustment screen; activating the image parameter values by activating the process button; and scanning the hardcopy document according to the image parameter values corresponding with the displayed digital image resulting in a digital document.
The present invention also relates to a reproduction system configured to execute the method according to the present invention.
2. Description of Background Art
Reproduction systems are known to include a scanner to scan hardcopy originals, e.g. paper originals and to create a digital document. Such a scanner may be a color scanner that can be used to produce a color scan of the hardcopy original. A reproduction system including a scanner may also include a print engine in order to print the digital document scanned from the hardcopy originals. The print engine produces a print of the hardcopy originals. Such a reproduction system usually has a local user interface or a remote workstation to be used by an operator or a user. The local user interface or the remote workstation includes a display for displaying image parameter values to be set before scanning of a hardcopy original and a setting device configured to prepare the reproduction system for the reproduction of the hardcopy original, for example for updating the set image parameter values. The display and setting device may be integrated into a touch screen.
A digital image is defined as a product of a scanning action. This product may take the form of a scan file being a number of bits of the digital image residing in a memory of the reproduction system. This scan file may take the form of a print out that is printed by the reproduction system on a receiving material based on the digital image. The digital image may be a colored digital image.
The intention of a user to scan a hardcopy document may be detected by means of a relevant event. Such an event may be opening a lid of a document feeder, putting in a hardcopy original in a document feeder or pushing a copy or scan button. Upon the detection of such an event, preparations may be carried out for the reproduction of the hardcopy original.
A preparing step for the reproduction of the hardcopy original is setting image parameters, for example for tuning of brightness, contrast and colors of the digital image.
When reproducing, e.g. copying or scanning, a hardcopy original, it may be very hard to make a satisfactory digital image, in particular, since no preview is available, because the hardcopy original has not been scanned yet. Reasons for this difficulty may be that the hardcopy original has color or contrast related problems, the scanner perceives the colors of the hardcopy original different from how the user sees them, or the printer has not been calibrated correctly.
Typically the user is offered a way to indicate to the reproduction system how the digital image should look by means of displaying a predetermined digital image at the display, e.g. the operator panel, according to image parameters that are set with initial image parameter values. These image parameters may be visualized with respect to the predetermined image and displayed by the display. The user may change these initial image parameter values in order to change the predetermined digital image into an image that shows the desired output.
However, this is not very helpful if the hardcopy original is not like the predetermined digital image.

Method for creating a digital document from a hardcopy document and a reproduction system


A light source device which is uniform in the intensity of distribution of an emitted light and high in the optical utilization efficiency, a display device which is high in recognability and is energy-saving, and an information terminal are provided. A reflecting portion is formed on a surface opposed to an emitting surface of a linear light guide. The reflecting portion is periodically formed with a total reflecting surface guiding a light incident on a linear light guide from a point light source, a light extracting surface allowing the light to reflect in such a way as to emit the light guiding the linear light guide from the emitting surface, and a re-incidence plane which takes the light transmitted but not reflected on the light extracting surface into the linear light guide again. By changing the size of the light extracting surface and the re-incidence plane, the intensity of distribution of the emitting light from the linear light guide can be made uniform.

1. Field of the Invention
The present invention relates to a light guide, a light source device equipped with the light guide and a display device using this device and an information terminal, and more in particular, it relates to a light source device having a light guide which is uniform in the intensity of distribution of an emitting light and high in emitting efficiency, and a display device which is high in cognizability and is in need of little electric power consumption and an information terminal equipped therewith.
2. Description of the Prior Art
Among the display devices, a liquid crystal display (LCD) is characterized by being light in weight and thin in size. Consequently, the LCD has been widely used as the display device for use of information processing terminals of a laptop type, a note type and the like or as the display device of various information terminals such as mobile electronic equipment including a portable type television, an electronic notebook, a portable telephone and the like. In general, in the LCD, the cognizability of information is enhanced by illuminating a display panel by a light source device.
As one of the light source devices used in the LCD, there is available an edge light type light source device, in which a light from the light source is allowed to enter from a side surface of a sheet-shaped light guide which becomes an emitting surface. Since the edge light type light source device is placed at the side surface of an almost bar-shaped light guide, the thickness of the whole light source device can be made nearly equal to the light guide. Consequently, it is possible for the edge light type light source device to be made thinner compared to a vertical type light source device having a light source placed in the front surface of the sheet-shaped light guide. Thus, in the LCD, use of the edge light type light source device has been prevailing.
As for the light source adopted for the edge light type light source device, there is available a point light source such as a light emitting diode (LED) and the like or a line light source such as a cold cathode fluorescent lamp (CCFL).
In FIG. 12 is shown a constitution of the light source device, in which a light from the point light source is turned into a line light source (turned into a linear light flux), and after that, it is allowed to enter the sheet-shaped light guide. The light source device 101 is constituted by the point light sources 102a, 102b, a linear light guide 103, and the sheet-shaped light guide 104. In a direction to which the point light sources 102a and 102b emit a light, there is provided the linear light guide 103, and in a direction to which the linear light guide 103 emits a light, there is provided the sheet-shaped light guide 104.
In the linear light guide 103, there is formed a reflecting portion 105 provided with a periodic concave-convex structure or a light scattering portion on a surface opposed to an emitting surface 103c. Further, in a sheet-shaped light guide 104, there is formed a reflecting portion 106 comprising the periodic concave-convex structure or the light scattering portion on the surface opposed to an emitting surface 104c.
The light which emits from the point light sources 102a and 102b and enters inside the linear light guide 103 from incidence planes 103aand 103b is reflected on a reflecting portion 105, so that it is turned into a line light source and is emitted outside of the linear light guide 103 from the emitting surface 103c. The light which emits from the linear light guide 103 and enters inside the sheet-shaped light guide 104 from an incidence plane 104a is reflected on a reflecting portion 106, so that it is turned into a sheet light source (turned into a sheet-shaped light flux) with its angle changed and is emitted outside of the sheet-shaped light guide 104 from an emitting surface 104c.
Although not shown in the drawing, the display device is disposed in such a way as to oppose to the emitting surface 104c of the sheet-shaped light guide 104. Incidentally, the light source device 101 is used as a back light in case of illuminating a transmission type display device, and as a front light in case of illuminating a reflection type display device. FIG. 12 shows a constitution adopting the light source device 101 as a front light.
Further, in FIG. 13 is shown a constitution of the light source device of a type which allows the light emitted by the line light source (such as CCFL and the like) to directly enter the sheet-shaped light guide. The light source device 101 is constituted by line light sources 108a and 108b, a sheet-shaped light guide 104,and reflectors 109a and 109b. Line light sources 108a and 108b are disposed by opposing to incidence planes 104a and 104b of the sheet-shaped light guide 104. The incidence planes 104a and 104b are covered by the reflectors 109a and 109b together with the line light sources 108a and 108b.
Incidentally, in the sheet-shaped light guide 104, there is formed a reflecting portion 106 comprising the periodic concave-convex structure or the light scattering portion on the surface opposed to the emitting surface 104c.
The light emitted from the line light sources 108a and 108b is reflected directly or in the reflectors 109a and 109b, and after that, it enters the sheet-shaped light guide 104 and is reflected in the reflecting portion 106, so that it is turned into a sheet light source.
Although not shown in the drawing, the display device is disposed in such a way as to oppose to the emitting surface 104c of the sheet-shaped light guide 104. Incidentally, FIG. 13 shows a constitution adopting the light source device 101 as a back light.
In recent years, demands for the enhancement of cognizability and reduction in electric power consumption for the LCD have been increased.
In the above-described edge light type light source device, the light entering the linear light guide or the sheet-shaped light guide from the light source repeats a reflection inside the light guide during the course of turning into a line light source or a sheet light source. At this time, the light is not only absorbed in the light guide and the light scattering portion, but the part thereof returns to the light source and the reflector so as to be absorbed there, and this causes an optical loss to reduce the emitting efficiency of the light guide. As a result, there is a problem in that the optical utilization efficiency of the light source device is lowered. Incidentally, what is meant by "the emitting efficiency of the light guide" is a ratio of the light which emits outside of the light guide from the emitting surface, to the light incident on the light guide from the incidence plane. Further, what is meant by "the optical utilization efficiency of the light source device" is a ratio of the light which illuminates the display device, to the light which is emitted from the light source.
To solve this problem, there is disclosed a method for enhancing the optical utilization efficiency of the light source device by modifying a shape of the linear light guide in Japanese Patent Laid-Open No. 2002-365439.
In FIG. 14 is shown a constitution of the invention disclosed in this publication. The light source device 101 is constituted by the point light sources 102a and 102b, the linear light guide 103, and the sheet light source 104. FIG. 14A is a top view and a front view schematically representing the light source device 101, and FIG. 14B is an enlarged view of the reflecting portion 105 of the linear light guide 103.
As shown in FIG. 14A, in a direction to which the light emits from the point light sources 102a and 102b, there is disposed the linear light guide 103, and in a direction to which the light emits from the linear light guide 103, there is disposed the sheet-shaped light guide 104.
The linear light guide 103, as shown in FIG. 14A, is narrowest in its width at the center, and is formed so as to become wide toward both end portions. In the linear light guide 103, there is formed the reflecting portion 105 on the surface opposed to the emitting surface 103c.
The reflecting portion 105, as shown in FIG. 14B, is constituted by a total reflecting surface 105a, which guides the light incident on the linear light guide 103 from the point light sources 102a and 102b (in other words, guides the light without causing an optical loss) and a light extracting surface 105b, which reflects the light advancing inside the linear light guide 103 in such a way that it emits from the emitting surface 103c. The light extracting surface 105b forms an almost V-shaped groove, and allows the light incident from both of the point light sources 102a and 102b to reflect. The total reflecting surface 105a and the light extracting surface 105b are formed in such a way as to gradually draw to the emitting surface 103c as it draws to the center from the end of the linear light guide 103. The linear light guide 103 is narrowest in its width at the center of the emitting surface 103c, and is formed in such a way as to become wide toward both end portions.
In the sheet-shaped light guide 104, there is provided the reflecting portion 106 comprising the periodic concave-convex portion or the light scattering portion on a surface opposed to the emitting surface 104c.
The light incident on the linear light guide 103 from the point light sources 102a and 102b is reflected on the reflecting portion 105, and after being turned into a line light source, it emits from the linear light guide 103, and enters the sheet-shaped light guide 104 from the incidence plane 104a of the sheet-shaped light guide 104. The light incident on the sheet-shaped light guide 104 is reflected on the reflecting portion 106 so as to be turned into a sheet light source, and emits from the emitting surface 104c.
As described above, the linear light guide 103 is narrowest in its width at the center and is wide toward both end portions. Consequently, the majority of the light incident on the linear light guide 103 from the point light sources 102a and 102b emits outside of the linear light guide 103 before reaching the center in which the width of the linear light guide 103 becomes narrowest, and this causes the number of reflection times to be reduced at the linear light guide 103. As a result, the optical loss at the linear light guide 103 is lowered, thereby enhancing the optical utilization efficiency of the light source device 101.
As for another method, there is a method disclosed in Japanese Patent Laid-Open No. 2001-243822, in which a shape of the reflecting portion of the sheet-shaped light guide is improved so as to enhance emitting efficiency of the sheet-shaped light guide.
In FIG. 15 is shown a constitution of the light source device of this publication. The light source device 101 is constituted by the point light source 102, the linear light guide 103, and the sheet-shaped light guide 104. FIG. 15A is a schematic top view and a schematic front view of the light source device 101, and FIG. 15B is an enlarged view of the reflecting portion 106 of the sheet-shaped light guide 104.
As shown in FIG. 15A, in a direction to which the light emits from the point light source 102, there is disposed the linear light guide 103, and in a direction to which the light emits from the linear light guide 103, there is disposed the sheet-shaped light guide 104.
Here, the linear light guide 103 is wedge-shaped. Further, in the sheet-shaped light guide 104, there is formed the reflecting portion 106 on the surface opposed to the emitting surface 104c. The reflecting portion 106, as shown in FIG. 15B, is constituted by the total reflecting surface 106a which guides the light incident on the sheet-shaped light guide 104, the light reflecting surface 106b which allows the light (advancing inside the light guide without causing a loss) which is guided inside the sheet-shaped light guide 104 to reflect in such a way as to emit from the emitting surface 104c, and a re-incidence plane 106c which takes the light transmitting the light extracting surface 106b into the sheet-shaped light guide 104 again. A tilt angle p of the light extracting surface 106b and a tilt angle q of the re-incidence plane 106c are in the relationship of p<q, p=45 to 65°, and q=80 to 90°.
The light emitted from the point light source 102 and incident on the linear light guide 103 is incident on the sheet-shaped light guide 104 after it is turned into a line light source by the linear light guide 103, and it is reflected on the reflecting portion 106, so that it is turned into a sheet light source.
In the light source device 101, a part of the light transmitted outside of the sheet-shaped light guide 104 from the light extracting surface 106b is incident again inside the sheet-shaped light guide 104 from the re-incidence plane 106c immediately after transmitting, and emits from the emitting surface 104 after it is reflected on the adjacent light extracting surface 106b. As a result, a number of reflection times at the sheet-shaped light guide 104 is reduced, and the optical loss at the sheet-shaped light guide 104 is lowered, thereby enhancing the optical utilization efficiency of the light source device 101.
Although the light source device 101 shown in FIG. 14 attempts to enhance the emitting efficiency by reducing the number of reflection times in the linear light guide 103, the intensity distribution of an emitted light from the linear light guide 103 is not made uniform because the number of reflection times is reduced. That is, as shown in FIG. 16A, the emitted light from the linear light guide 103 shows the intensity distribution in which it is strong in the vicinity of both end portions (incidence planes 103a and 103b) of the linear light guide 103 and becomes weak as it draws to the center portion. As a result, the uniformity of the intensity distribution of the emitted light from the light source device 101 becomes low, and the cognizability of the display device using the light source device 101 is also lowered.
Further, the same is applicable to the light source device 101 shown in FIG. 15. As shown in FIG. 16B, the emitted light from the sheet-shaped light guide 104 shows the intensity distribution in which it is strong in the vicinity of the end portion (incidence plane 104a) of the sheet-shaped light guide 104 and becomes weak as it is apart from the incidence plane 104a.
On the other hand, in Japanese Patent Laid-Open Nos. 2001-332112 and 2002-40420, there is disclosed an invention aiming at the uniformity of the intensity distribution of the emitted light from the light guide.
In FIG. 17 is shown a constitution of the invention disclosed in these patent publications. A light source device 200 has a depth of a wedge-shaped reflection groove deepened as the groove is apart from the light source in order to enhance the uniformity of the intensity of the emitted light from the light guide. In this way, in the center portion of the light guide, an amount of light incident on the wedge-shaped reflection groove is increased, so that the intensity distribution of the light emitted from the light guide is made uniform.
However, in the case of such constitution, since the depth of the groove is limited by a groove pitch and a groove angle, among the light incident on the light guide, an almost-parallel light is unable to reflect effectively on the groove. As a result, the optical loss arising from the light being repeatedly reflected inside the light guide or the light being emitted from the incidence plane opposite to the incidence plane where it is incident becomes large so that the optical utilization efficiency of the light source device is lowered. That is, an amount of emitted light from the light guide is uniformed in a low state of utilization efficiency, and cognizability of the display device using this light guide becomes low.
In this way, it has been impossible for the light guide equipped with a conventional light source device to allow both the uniformity of the intensity distribution of the emitted light and the enhancement of emitting efficiency to be compatible.
The present invention has been made in view of the above-described problems, and its object is to provide a light guide which is high in emitting efficiency and uniform in the intensity distribution of the emitted light, a light source device equipped with this guide, a display device adopting this device, and an information terminal.

Light guide, light source device, display device and information terminal equipped therewith


A display screen inspection method according to the present invention takes a display screen of a display device as an inspection subject and makes decisions on defects of the display screen. The method includes performing a separation between display operating portions and display non-operating portions of the inspection subject present in a gray image from image data of individual pixels of the gray image obtained by picking up an image of the inspection subject, selectively extracting image data of only proper display operating portions and compressing the image data to be inspected for defects, and inspecting the selectively extracted image data for any defects.

The present invention relates to a method for inspecting a display screen. More specifically, the invention relates to a display screen inspection method for automatically deciding the conformity of inspection results in the production line with respect to inspections for point defects and the like on display devices used in electronic equipment and other fields, such as liquid crystal panels, shadow masks, CRT panels, and plasma displays.
As a method for reading the screen displayed on a display device, there has been provided, as a primary method, one using two-dimensional CCD area sensors.
Generally, pixels arrayed in columns and rows of two-dimensional sensors, and pixels arrayed in columns and rows of a display device are associated with each other (hereinafter, unless otherwise specified, pixels of the display device will be referred to as "display pixels", and pixels of the sensors will be referred to as "sensor pixels"), where the pixel arrangement is such that a plurality of sensor pixels are associated with one display pixel.
This is explained by taking a case of a display device of a liquid crystal panel consisting of 640.times.400 pixels as an example. A liquid crystal panel includes display operating portions and display non-operating portions of the pixels. Point defects in the dynamic operating inspection for these display operating portions can be classified into dark dots, which are a group of display pixels that will not operate for display in the displaying state of the liquid crystal panel although they are originally intended to be a display operating portion, and bright dots, which are a group of display pixels that will operate for display in the non-displaying state although they are originally intended to be a display non-operating portion. For example, in an automatic inspection for this, when three sensor pixels are assigned to one display pixel, approximately 2000 pixels are required in the row direction.
As an example of the conventional method, there has been adopted a method in which the position where the image is focused on the CCD surface is shifted by moving the lens system of CCD area sensors in advance so that contrast differences between display operating portions and display non-operating portions of the display device will not occur. Hereinafter, the state in which the image is focused on the CCD surface is referred to as a "focused state," and the state in which the image cannot be focused is referred to as a "defocused state."
Now consider a display pixel 100 as shown in FIG. 10A. Assume that a dark-dot defect 101, as shown in FIG. 10A, is present on this display pixel 100. FIG. 10B shows density distribution data in the focused state at ten display operating portions on a one-dimensional reference line 102 on the display pixel 100, where display operating portions 103 and display non-operating portions 104 are part of them. Also, the dark-dot defect 101 is present in this density distribution data. FIG. 10C shows density distribution data in the defocused state of the display pixel 100, where a dark-dot defect portion 105 (a defocused state of the dark-dot defect 101) is present in a background density 106. This background density 106 is a defocused state part of the display operating portion 103 and the display non-operating portion 104.
This conventional method is frequently used for large degrees of point defects, being an effective method. A contrast difference between display operating portions and display non-operating portions in this case refers to a contrast difference in the sensor pixel that has received light.
However, the aforementioned conventional method raises the following issues.
Making a defocused state, as described above, would result in reduced contrast differences between point-defect portions and normal portions, such that the method could not maintain enough detection ability for small degrees of point defects. In other words, making a defocused state until the difference between the display operating portions and the display non-operating portions of the display device is nullified would cause the contrast differences of small degrees of point defects to be eliminated. Thus, the conventional method has a disadvantage of being incapable of detecting such small degrees of point defects.
In some cases, it is necessary to decide whether or not the position of a display operating portion of the display device is normal. However, as described above, making a defocused state would make it difficult to decide where the proper position of the display operating portion should be.
In other cases, it is necessary to decide whether or not the size of a display operating portion of the display device is normal. However, as described above, making a defocused state would make it difficult to decide how the proper size of the display operating portion should be.

Matsushita Electric Industrial Co., Ltd.