A process for color overprinting onto a thermally printable receiving surface includes using a thermal printer and transfer foils to print a first layer of color printing medium onto a portion of a receiving surface, and then using the thermal printer to print at least a second layer of translucent colored printing medium onto the receiving surface on top of the first layer. An index of overprint colors can be created by the process for use in matching colors printable by the overprinting process to the colors on an original graphic. The index may be used manually or in a computerized printing process to determine the number of transfer foils required to reproduce an original graphic, and their order of use.

The accurate reproduction of colored graphics has proven difficult using known color printing methods. This is primarily due to the fact that the methods employed to accomplish the reproductions are incapable of producing the high fidelity color and quality of the original image. One known method used to produce colored graphics employs the three process colors (cyan, magenta and yellow) to reproduce an image by first conducting a color analysis on the original and then making what are known as color separations and finally, printing the image. In the past, color separations were created by placing a red, green, and blue filter respectively over the lens of a camera and shooting a separation negative using panchromatic film (film sensitive to the visible portions of the spectrum). Use of these filters produced cyan, magenta and yellow separation negatives. Thus, these separations yielded a record of the amount and concentrations of the three process colors contained in the original. The color information contained in the negatives is then fed into a printer. The various tones and colors of the original image are approximated by printing patterns of various sized dots next to one another using each process color. When the final image is viewed, the dots tend to blend together to create what appears to be the colors corresponding to the colors found on the original image.
Historically, the dot patterns were determined using the halftone separation technique described above along with what is known as a halftone screen which was placed over the film during exposure to break up the image from the original copy into grids corresponding to the dot patterns to be printed. The dot patterns obtained from the combination of the halftone screen and the separation negatives, known as halftone dots, were then transferred to the printer which printed the patterns corresponding to each process color onto a receiving surface, thereby reproducing the original image.
More recently, the color analysis and halftone separations have been carried out in a single step using a color scanner and computer in combination with a printer. The color scanner evaluates the colored original point by point through color filters. The image is then converted from a visual to an electrical impulse that is fed into a computer. The computer then compiles this information and uses it to control a printer.
One type of printer particularly suited for printing the halftone dot patterns according to the information obtained from a scanned original is known as an ink jet printer. Typically, this type of printer uses a print head having three ink reservoirs each carrying a process colored (cyan magenta and yellow) ink. During a printing process, the print head traverses the image receiving surface and simultaneously prints the halftone dot patterns according to the color separations accomplished by the scanner and computer.
A problem often encountered with the images created by the above described process is that the patterns of dots are clearly visible. This causes the image to appear less sharp and in some cases even grainy. This is especially undesirable in situations where the images produced will be subject to close scrutiny. Accordingly, there is a need for a color image production technique which accurately reproduces an original using solid continuous colors. As used herein, the term continuous should be construed to mean that the appropriate portion of the receiving surface upon which the color is transferred is completely filled with color and contains no dots.
In addition to the foregoing, the previously described process is not capable of accurately reproducing many colors or shades of color. For instance the appearance of some subtle pastels cannot be duplicated using only the three process colors. Therefore, in some instances it may not be possible to acceptably reproduce a particular image.
A known method used to produce solid continuous colors, incorporates a thermal printer. Donor foils are utilized by the thermal printer, from which layers of color pigment are transferred to a receiving surface. The phrase "donor foil" is a term of art which denotes in one aspect, a foil or other thin material which carries a layer of pigment dispersed in a wax, resin, or wax-resin vehicle. The pigment is transferred from the foil to the receiving surface by the thermal printer through a combination of heat and pressure. Alternatively, in a second aspect, a donor foil can take the form of a dye diffusion foil or other thin material, wherein the foil or other thin material is impregnated with a transferable dye which when exposed to the heat and pressure produced by the thermal printer, diffuses out of the foil or other thin material and onto the print media. While this printing method consistently produces high quality continuous colors, it is limited by the available number of donor foil colors. The color of the dye or pigment carried by a donor foil is referred to by those skilled in the art as a "spot color." The finite number of available spot colors, has, until recently, caused this method of printing to be considered inappropriate for the accurate continuous color reproduction of images.
Based on the foregoing, there is a current need for a method of producing an expanded palette of solid continuous colors and shades of color producible from a limited number of donor foil colors. This method should be capable of producing the same high fidelity appearance on the print media, as is embodied in the original graphic. It is also important that the method employ a means of identification as well as the associated formula needed to reproduce each color and shade such that an operator is able to readily ascertain and print the desired color.
In accordance with the foregoing, it is the general object of the present invention to provide a greatly expanded palette of printable high fidelity continuous colors and shades, producible using a limited number of spot colors.
A further object of the present invention is to provide a means whereby these colors, and the formulas for their production are codified in an easily accessible fashion.

Method and apparatus for thermal transfer color printing


High-affinity oligonucleotide ligands to the thermostable Taq polymerase and Tth polymerase are disclosed. Specifically disclosed are DNA ligands having the ability to bind to the Taq and Tth polymerases and the methods for obtaining such ligands. The ligands are capable of inhibiting polymerases at ambient temperatures.

The Polymerase Chain Reaction (PCR), is a recently developed technique which has had a significant impact in many areas of science. PCR is a rapid and simple method for specifically amplifying a target DNA sequence in an exponential manner. Briefly, the method consists of synthesizing a set of primers that have nucleotide sequences complementary to the DNA that flanks the target sequence. The primers are then mixed with a solution of the target DNA, a thermostable DNA polymerase and all four deoxynucleotides (A, T, C and G). The solution is then heated to a temperature sufficient to separate the complementary strands of DNA (approximately 95.degree. C.) and then cooled to a temperature sufficient to allow the primers to bind to the flanking sequences. The reaction mixture is then heated again (to approximately 72.degree. C.) to allow the DNA synthesis to proceed. After a short period of time the temperature of the reaction mixture is once again raised to a temperature sufficient to separate the newly formed double-stranded DNA, thus completing the first cycle of PCR. The reaction mixture is then cooled and the cycle is repeated. Thus, PCR consists of repetitive cycles of DNA melting, annealing and synthesis. Twenty replication cycles can yield up to a million fold amplification of the target DNA sequence. The ability to amplify a single DNA molecule by PCR has applications in environmental and food microbiology (Wernars et al. (1991) Appl. Env. Microbiol. 57:1914-1919; Hill and Keasler (1991) Int. J. Food Microbiol. 12:67-75), clinical microbiology (Wages et al. (1991) J. Med. Virol. 33:58-63; Sacramento et al. (1991) Mol. Cell Probes 5:229-240), oncology (Kumar and Barbacid (1988) Oncogene 3:647-651; McCormick (1989) Cancer Cells 1:56-61), genetic disease prognosis (Handyside et al. (1990) Nature 344:768-770), blood banking and forensics (Jackson (1990) Transfusion 30:51-57).
The availability of thermostable DNA polymerases such as Taq DNA polymerase has both simplified and improved PCR. Originally only heat-sensitive polymerases, such as E. coli DNA polymerase were available for use in PCR. Heat-sensitive polymerases, however, are destroyed at the temperatures required to melt double-stranded DNA, and additional polymerase has to be added after each PCR cycle. Taq DNA polymerase, isolated from the thermophilic bacterium Thermus aquaticus, is stable up to 95.degree. C. and its use in PCR has eliminated the necessity of repetitive addition of temperature sensitive polymerases after each thermal cycle. Additionally, because Taq polymerase can be used at higher temperatures it has improved the specificity and sensitivity of PCR. The reason for the improved specificity is that at higher temperatures the binding of promoters to sites other that the desired ones (referred to as mispriming) is significantly reduced.
Since its discovery, the Polymerase Chain Reaction has been modified for various applications, such as in situ PCR, in which the detection limit of traditional in situ hybridization has been pushed to the single copy level (Haase et al. (1990) Proc. Natl. Acad. Sci., USA 87:4971-4975), and reverse transcriptase PCR (RT-PCR), wherein an RNA sequence is converted to its copy DNA (cDNA) by reverse transcriptase (RT) before being amplified by PCR, making RNA a substrate for PCR (Kawasaki (1991) Amplification of RNA in PCR Protocols, A Guide to Methods and Applications, Innis et al., Eds. Academic Press Inc., San Diego, Calif., 21-27). Mesophilic viral reverse transcriptases, however, are often unable to synthesize full-length cDNA molecules because they cannot "read through" stable secondary structures of RNA molecules. This limitation has recently been overcome by use of a polymerase isolated from Thermus thermophilus (Tth polymerase). Tth polymerase is a thermostable polymerase that can function as both reverse transcriptase and DNA polymerase (Myers and Gelfand (1991) Biochemistry 30:7662-7666). The reverse transcription performed at an elevated temperature using Tth polymerase eliminates secondary structures of template RNA, making it possible for the synthesis of full-length cDNA.
Although significant progress has been made in PCR technology, the amplification of nontarget oligonucleotides due to side-reactions, such as mispriming of background DNA and/or primer oligomerization still presents a significant problem. This is especially true in diagnostic applications in which PCR is carried out in a milieu containing background DNA while the target DNA may be present in a single copy (Chou et al. (1992) Nucleic Acid Res. 20:1717-1723). It has been determined that these side reactions often occur when all reactants have been mixed at ambient temperature before thermal cycling is initiated.
Two methods have been reported which minimize these side reactions. In the first method, termed "hot start" PCR (Chou et al. (1992) Nucleic Acid Res. 20:1717-1723; D'Aquila et al. (1991) Nucleic Acid Res. 19:3749), all of the reagents are heated to 72.degree. C. before adding the final reagent, usually the polymerase. Although this method does increase specificity, thereby reducing side products, the method is inconvenient for dealing with a large number of samples, the reaction mixture can become more easily contaminated, and the method is error-prone.
In the second method, a neutralizing antibody to Taq (referred to as TaqStart) is added to the complete reaction mixture. This antibody inhibits the polymerase activity at ambient temperature (Kellogg et al. (1994) Biotechniques 16:1134-1137), but is inactivated by heat denaturation once the reaction is thermocycled, rendering the polymerase active. The drawback of this approach to reducing side products is that the anti-Taq antibody should be stored at -20.degree. C. until use, which means that detection kits should be packaged and shipped under controlled environment adding to their cost. In addition, a significant amount of antibody (.about.1 .mu.g of antibody/5 U of Taq) is needed for a single PCR.
The development of high affinity nucleic acid ligands capable of inhibiting the thermostable Taq and Tth polymerases would obviate the need for the "hot start" method and would overcome the limitations associated with the second method. Nucleic acid inhibitors can be developed that are extremely specific and have high affinity. Since nucleic acids are more stable than proteins at ambient temperature, the shipping and packaging problems associated with using antibodies can be overcome. Additionally, nucleic acids, like antibodies will lose their affinity for the polymerase at higher temperatures, allowing the polymerase to be activated when desired. The potential for mispriming mediated by nucleic acid based inhibitors themselves functioning as primers (in addition to the specific primers used in the reaction) in PCR can be eliminated by capping their 3' ends.

Nucleic acid ligand inhibitors to DNA polymerases


A method for molding an article by dip or slush molding. The method includes the step of providing a flexible, heat resistant mold member. The mold member maintains its structural integrity during further heating and curing steps. Thus the mold member may therefore be used as an insert in the article to provide flexible stability at specific locations within the article. The mold member is made of a material which is substantially non-reactive with the molded article. The article may be any article made from a plastisol; in particular it can be a binaural for a stethoscope having a single or double lumens.

Special problems are presented in the manufacturing process of molded articles, which are intended to have internal bores, cavities, or voids. The bores, cavities, or voids of the completed molded article may be filled with other structural components such as springs, connector bushings, and the like. The dimensions of the internal cavities must be established and maintained during the manufacturing process, in order that such inserts may be properly assembled later.
Even more difficult is the manufacturing process where the internal cavities are intended to transmit sound, air, or other fluids where the internal dimensions of the cavities are critical to the properties of the fluids moving therethrough.
The manufacture of molded articles having internal cavities such as stethoscopes accentuate the difficulties of manufacturing because the sound passages must have certain acoustical qualities in order to permit the physician to accurately hear the condition of the patient under examination.
The acoustical passages of the stethoscope, the lumens, may transmit the sound from the patient to one ear of the physician, called a monaural tubing, or to both ears of the physician, called a binaural tubing. The sound passages in the stethoscope may have a common internal cavity, or single lumen, from the patient to the yoke of the stethoscope, whereupon the single lumen divides into two passages, one for each ear of the physician.
Alternately, the stethoscope may have double lumens from the microphone placed against the patient to the yoke of the stethoscope, whereupon the pair of lumens divide, one to each ear of the physician.
As can be appreciated by those skilled in the art, the molding of a long, narrow object, having at least one, and preferably two, internal passageways presents considerable manufacturing difficulties where the acoustical quality of the stethoscope is directly dependent upon the structural configuration of the lumens between the microphone and the ear of the physician. In this regard, U.S. Pat. No. 4,200,169 discusses the importance of the configuration of internal binaural lumen passages and the resolution of acoustical quality in the stethoscope of that invention by the substantial maintenance of a constant diameter throughout the lumens.
Often, stethoscopes are manufactured using the process of hot dip molding. A mold is assembled, heated, and dipped into a liquid plastic or plastisol to permit the plastisol to contact all surfaces of the mold. The amount of plastisol which gels around the mold is related to the heat of the mold when it enters the plastisol reservoir. The mold is withdrawn from the plastisol reservoir and is heated to cure the plastisol into the plastic article comprising the binaural tubing of the stethoscope. The segments of the mold are removed, leaving the internal passages, or lumens, within the binaural tubing. The other components of the stethoscope are attached to the binaural to complete the manufacture of the stethoscope.
Some portions of the mold may require additional thickness of the plastisol in order to provide greater structural stability of the article after molding during usage by the physician. The yoke of the stethoscope, where the lumens separate and are directed to each ear, is a particularly vulnerable portion of the stethoscope during the stress and strain of usage. And the yoke portion of the mold must counteract the force of gravity during the manufacturing process as the plastisol flows on the mold as the mold moves from one area of manufacture to the next. Therefore, that portion of a dip-molding form is subjected to direct, additional heating to achieve additional gelation of the plastisol about that portion of the form to counteract plastisol flow and reinforce a critical junction of the molded article.
The additional steps of direct heating of critical portions of the form to provide additional wall thickness for the molded article is known as the process of "building". Thus, when stethoscopes are manufactured using hot dip molding, it is necessary in the molding of the binaural tubing to "build" sufficient wall thickness at critical portions of the binaural tubing without compromising the desired acoustical quality of the binaural lumens being formed therein.
Currently, as known to those skilled in the art, whenever sufficient wall thickness must be "built", the mold is placed before an open flame in the specific area of the mold requiring "building". Use of an open flame in a manufacturing process is an inexact method at best, even for "build" formation. Atmospheric or climatic conditions, temperature of the flame, and subjective opinions of the manufacturer establishing the processing conditions for the open flame "building" all result in an unpredictible and potentially non-replicating manufacturing process step for the formation of a stethoscope which demands replicated acoustical qualities. Further, the presence of open flames in manufacturing processes represents a potential dangerous manufacturing condition in the presence of any combustible materials or gases.
Molds intended for complete removal after a hot dip molding process are typically made entirely of a material capable of withstanding the temperatures of pre-heating, including "build" temperatures during pre-heating, and curing. However, unfortunately, such heat resistant materials are also rigid and not nearly as flexible as the article molded from the plastisol.
In the case of stethoscopes, the entire length of the binaural tubing must have sufficient flexibility to facilitate use by the health care practitioner. In other words, the molded stethoscope must be flexible along the entire length of its tubing to permit comfortable placement about the head of the health care practitioner and to flex at various locations in order to reach that portion of the body of the patient requiring examination.
If it were desired to avoid the use of an open flame in order to "build" wall thickness at portions of a stethoscope subject to stress and strain during usage, the only molds available to those skilled in the art are heat resistant materials which are rigid and not nearly as flexible as the article to be molded from the plastisol.
Thus, if the rigid mold were left in the stethoscope, after molding was complete, that rigid mold or mold segment would severely interfere with the flexibility and proper use of the stethoscope. Moreover, where a rigid mold or a mold segment is left in the stethoscope, the yoke junction of the stethoscope where the lumens divide would be subject to undesirable pressure and movement as the yoke is flexed.
Hence, what is needed in the art is a method for molding articles which eliminates any necessity of open flame "building" along those portions of the articles which require flexible yet stable junctions, like the yoke portion of the stethoscope. The art also needs a mold which has a member which is both heat resistant and flexible which optionally may remain embedded in the molded article after molding to augment the stability of the molded article at the critical junction, obviating the need for open flame "building" of additional wall thickness.

Method of forming a molded article using a mold having an elastomeric mold member

Minnesota Mining and Manufacturing Company


An optical transmission method and device consisting of coding a binary data pattern (SI) to be transmitted in the form of a second binary signal (SM), by differential coding; filtering the second binary signal (SM) to obtain a duobinary signal (SMF having three meaningful values (-1, 0.+-..epsilon., +a) and a narrower bandwidth; and modulating an optical carrier according to the values assumed by the filtered signal (SMF), the modulated carrier having a maximal amplitude to represent the maximal value (+a) and the minimal value (+a) of the duobinary signal (SMF), the phase of the modulated carrier being shifted by .theta..sub.1 and .theta..sub.2 =.theta..sub.1 +180.degree., respectively, and a minimal amplitude to represent values (0.+-..epsilon.) near 0 if the duobinary signal. The method of this invention is suitable for long distance fiber-optic transmissions.

The invention concerns a fiber optic transmission method having reduced sensitivity to chromatic dispersion caused by the fiber; a transmission device and system for implementing this method.
The maximal transmission distance over a repeaterless optical fiber is limited by attenuation and chromatic dispersion. Erbium-doped optical fiber amplifiers can correct the attenuation but the chromatic dispersion remains a major limitation in the case of signals having a high bit rate, for example 10 Gbit/s. Various prior art methods can compensate chromatic dispersion on a given fiber section, at least in part.
Other prior art methods are directed to making the transmission less sensitive to chromatic dispersion, without changing the latter. For example, the article "10 Gbit/s unrepeated three-level optical transmission over 100 km of standard fibre" by X. Gu and L. C. Blanck published in Electronics Letters, 9th Dec. 1993, vol. 29, n.degree. 25, describes a method consisting of:
encoding a data pattern to be transmitted in the form of a duobinary signal, i.e. a signal which can assume values approximately equal to +1, 0 and -1, by reducing the bandwidth of a binary signal; PA1 modulating an optical carrier with the values assumed by this signal, to obtain an amplitude modulated carrier at three different levels; PA1 transmitting the modulated carrier over an optical fiber without using any particular method of compensating chromatic dispersion; PA1 demodulating the optical signal received at the distant end of the optical fiber using a photoreceiver supplying an electrical signal representative of the amplitude of the received optical signal, and comparing this signal with two reference values to reconstitute two binary signals in parallel; and PA1 decoding the two binary signals to restore the data pattern. PA1 a data pattern is coded in the form of a ternary modulation signal which can assume three meaningful values: a maximal value, a minimal value and an intermediate value between the maximal value and the minimal value; and PA1 an optical carrier is modulated according to the values assumed by the modulation signal; PA1 characterized in that, to modulate said carrier, the carrier is transmitted with: PA1 the data pattern is coded in the form of a binary signal if it is not already in this form; PA1 this binary signal is coded in the form of another binary signal by differential coding; and PA1 this other binary signal is filtered to reduce its bandwidth and thereby obtain a ternary signal. PA1 means for coding a data pattern to be transmitted in the form of a ternary modulation signal which can assume three meaningful values: a minimal value, a maximal value and an intermediate value between the maximal value and the minimal value; and PA1 means for modulating an optical carrier according to the values assumed by the modulation signal; PA1 and characterized in that the optical carrier modulator means include a modulator supplying a modulated carrier having: PA1 means for coding said data pattern in the form of a binary signal if it is not already in this form; PA1 means for coding the binary signal in the form of another binary signal by differential coding; and PA1 means for filtering the other binary signal to reduce its bandwidth and thereby to obtain a ternary signal. PA1 means for coding said data pattern in the form of a ternary signal with three discrete levels if it is not already in this form; and PA1 optional means for filtering the ternary signal by reducing its bandwidth. PA1 a transmitter device for modulating an optical carrier with a data pattern; PA1 an optical transmission link one end of which is coupled to an output of the transmitter device; PA1 means for demodulating the modulated optical carrier having an input coupled to a second end of the link and supplying a signal representing the envelope of the power of the modulated optical carrier; and PA1 a comparator for comparing the signal to a reference value and deducing a binary signal representing the data pattern transmitted; PA1 characterized in that it includes a transmitter device in accordance with the invention.
The use of duobinary coding and amplitude modulation reduces the bandwidth occupied by the signal transmitted. This reduces the effect of chromatic dispersion and therefore significantly increases the maximal transmission distance. Another advantage is that the optical transmitter and optical receiver can have a narrower bandwidth than in the case of conventional transmission in which the carrier is amplitude modulated by a binary signal.
However, this prior art method has a drawback: it is necessary to discriminate three different amplitude levels in the electrical signal supplied by the photodetector. Discriminating three levels is much more difficult than discriminating two levels as required for amplitude modulation by a binary signal. Also, the signal/noise ratio is lower than that which would be obtained with a binary signal.

Optical transmission method with reduced sensitivity to dispersion, transmission device and system for implementing this method


A device for heat treatment of continuous material webs with hot steam has a substantially sealed housing having at least one chamber, a blower having a shaft, a drive arranged outside of the housing and connected with the shaft with the blower, a heater provided with conduit for supplying gaseous or liquid substances, nozzles with nozzle openings facing toward a material web to be heat treated, an element for transporting the material to be treated through the housing, the housing having a bottom, the shaft and the conduits extending through the bottom of the housing.

The present invention relates to a device for heat treatment of continuous material webs by blowing of hot steam.
A drying in pure hot steam is very efficient, since it is not necessary to heat any air coming from outside. This is described in the book "Drying and drying processes" of K. Kroll, Springer-verlag 1959, page 37. Additional factors also contribute to the efficiency of this matter, such as the fact that waste air cleaning is dispensed with since no waste is produced. The latent heat contained in the waste steam can be recovered relatively simple by condensation. Because of the low density of the steam, the consumption of electrical energy for recirculation of the drying medium is approximately 1/3 lower than in driers operating with hot air. A further advantage which is especially important for drying textiles is described in the above mentioned book on page 177. The heat steam drying improves the material web, imparts a good feel to it, and allows the colors to appear fresh and clear. The hot steam drying can be provided not only for material webs of natural fibers, but also for such material webs which are produced from synthetic fibers. They can be treated with temperatures of 100-300.degree. C.
The German document DE 35 11 950 discloses a heat steam dryer, from which the present invention is derived. The material web is brought for example by tensioning chains through a slot formed in the bottom of the housing, and can be guided in and out of the housing through the slot. The slot is provided with special seals.
As disclosed in the above mentioned book on page 103, it is not very simple in the practice to form a heat steam dryer for a continuous operation, for example for fabric webs, so tight that no air can penetrate into it. The problems arise not only with the slot for the material web-guiding tensioning chain, but also for example for conduits which extend through the housing wall, doors, or passages for a sieve.

Device for heat treatment of continuous material webs


A Wireless Monitoring Apparatus is used in conjunction with an automated external defibrillator (AED) system for patient rescue in mass-casualty incidents. The rescuer applies the device on each patient. The wireless monitoring apparatus automatically analyzes the patient's heart rhythm and communicates with the AED system. The AED system is therefore is able to display information with regard to each patient, notifies the rescuer on actions to take and can deliver defibrillation therapy if needed.

In mass casualty incidents such as transportation, terrorist or military, rescuers must treat several patients at the same time, requiring several AEDs or a new system adapted to monitor several patient's vital signs at the same time and provide defibrillation therapy when necessary. Such a system that can monitor several patients at the same time allows a single rescuer to treat patients in a triage situation. Such an example is a military doctor or trained individual that must treat several soldiers after attack from an explosive device. Such an individual using a new system adapted to treat the critically wounded soldiers may be the difference between life and death in remote locations such as open battlefields where medical doctors and/or hospitals may be inaccessible. The system itself uses wireless communications to exchange information (via transceiver) with regard to the patient's vital signs and other relevant information. The rescuer applies the monitoring apparatus directly to the bare skin patient's chest. The apparatus then analyzes the patient's ECG for cardiac arrest, communicates the information to the AED and the AED alerts the rescuer that a soldier is in cardiac arrest and requires defibrillation therapy. The rescuer can then quickly provide therapy and continue monitor the other soldiers.

This patent is subject to a terminal disclaimer.

Wireless monitoring apparatus used in conjunction with an automated external defibrillator (AED) system for multiple patient rescue during mass casualty incidents


A method of growing a group III nitride crystal grows a group III nitride crystal from a solution in which an alkaline metal, a group III metal and nitrogen are dissolved, and includes, in the solution, a material which increases solubility of the nitrogen into the solution.

This application claims the benefit of Japanese Patent Applications No.2003-019716 filed Jan. 29, 2003, No.2003-071302 filed Mar. 17, 2003, No.2003-081836 filed Mar. 25, 2003, No.2004-011536 filed Jan. 20, 2004, No.2004-013562 filed Jan. 21, 2004, and No.2004-012906 filed Jan. 21, 2004, in the Japanese Patent Office, the disclosures of which are hereby incorporated by reference.
The present invention generally relates to methods of growing group III nitride crystals, group III nitride crystals grown thereby, group III nitride crystal growing apparatuses and semiconductor devices, and more particularly to a method of growing a group III nitride crystal which is suited for use in semiconductor devices such as violet light sources which may be used for writing and/or reading information to and/or from optical disks, ultraviolet light sources such as laser diodes and light emitting diodes, violet light sources which may be used for electronic photography, and group III nitride electron devices. The present invention also relates to a group III nitride crystal and a semiconductor device which are produced using the method of growing the group III nitride crystal, and to a group III nitride crystal growing apparatus for growing such a group III nitride crystal.
Existing InGaAlN (group III nitride) devices which are used for violet, blue and green light sources are generally made by using crystal growing methods such as Metal Organic Chemical Vapor Deposition (MO-CVD) and Molecular Beam Epitaxy (MBE) to grow the InGaAlN (group III nitride) crystal on a sapphire or SiC substrate. But when the sapphire or SiC substrate is used, crystal defects increase due to large differences between the coefficient of thermal expansion and the lattice constant of the InGaAlN (group III nitride) crystal and the coefficient of thermal expansion and the lattice constant of the sapphire or SiC substrate. As a result, device performances of the semiconductor devices having the InGaAlN (group III nitride) grown on the sapphire or SiC substrate deteriorate, thereby making it difficult to extend the serviceable life of the light emitting devices, for example, and increasing the power required to operate such semiconductor devices.
Furthermore, in the case of the sapphire substrate which is insulative, it is impossible to draw out the electrodes via the substrate as done in the conventional light emitting devices. Consequently, when the sapphire substrate is used, the electrodes must be drawn out via the group III nitride crystal layer which is grown on the sapphire substrate. As a result, the device area becomes large and it becomes difficult to reduce the cost of such semiconductor devices.
In addition, in the case of the semiconductor device having the group III nitride crystal grown on the sapphire substrate, it is difficult to separate the chips by slicing, and it is not easy to obtain a resonator end surface required by the laser diode by cleavage. For this reason, existing techniques form the resonator end surface by dry etching or, polishes the sapphire substrate to a thickness of 100 μm or less before forming the resonator end surface by a process similar to cleavage. But according to these existing techniques, it is impossible to easily perform the formation of the resonator end surface and the chip separation in a single process as done in conventional laser diodes. Accordingly, these existing techniques require complex processes and increase the cost of the semiconductor devices.
In order to solve the problems described above, a technique was proposed to reduce the crystal defects by taking measures such as selectively growing the group III nitride crystal in a lateral direction on the sapphire substrate. According to this proposed technique, it is possible to reduce the crystal defects compared to a case where a GaN layer is not selectively grown in the lateral direction on the sapphire substrate. However, the above described problems associated with the insulation and the cleavage caused by the use of the sapphire substrate still exist. Furthermore, this proposed technique requires complex processes, and the sapphire substrate warps due to the growing of the GaN layer on the sapphire substrate since sapphire and GaN have different properties. As a result, the cost of the semiconductor device becomes high when this proposed technique is employed to make the semiconductor device.
In order to solve these problems, it is desirable to grow on the substrate a layer which is made of the same material as the substrate. In the case described above, it is desirable to grow the GaN layer on a GaN substrate. Hence, research is being made to grow the crystal of bulk GaN by vapor phase deposition, solution growth and the like. However, a GaN substrate having a practical size and a high quality has yet to be realized.
One method of realizing the GaN substrate is proposed in H. Yamane et al., "Preparation of GaN Single Crystals Using a Na Flux", Chem. Mater. 1997, Vol. 9, pp. 413-416. This proposed method grows the GaN crystal using Na as flux. More particularly, this proposed method uses NaN3 and Ga as raw materials, and seals the raw materials in a nitrogen atmosphere within a stainless steel reaction chamber which has an internal diameter of 7.5 mm and a length of 100 mm, for example. The GaN crystal is grown by maintaining the reaction chamber at a temperature of 600° C. to 800° C. for 24 hours to 100 hours.
In the case of the proposed method according to H. Yamane et al., the Ga crystal can be grown at a relatively low temperature of 600° C. to 800° C. In addition, the pressure within the reaction chamber is on the order of approximately 100 kg/cm2 and is relatively low. Hence, the growth condition of this proposed method is practical.
However, the problem with this proposed method is that the size of the obtained crystal is on the order of approximately 1 mm or less and small. In other words, the reaction chamber used in H. Yamane et al. is a completely closed system, and the raw materials cannot be supplied from outside the reaction chamber. For this reason, the raw materials are depleted during the crystal growth and the crystal growth stops, thereby making the size of the obtained crystal on the order of approximately 1 mm and small. From the practical point of view, the crystal having such a small size is unsuited for making the semiconductor device.
In view of the above, first and second methods were respectively proposed in Japanese Laid-Open Patent Applications No.2001-58900 and No.2001-102316.
FIG. 1 is a cross sectional view showing a crystal growing apparatus used by the first method. As shown in FIG. 1, a growth chamber 102 and a group III metal supply pipe 103 are provided within a reaction chamber 101. External pressure is applied to the group III metal supply pipe 103 from outside the reaction chamber 101, so as to additionally supply a group III metal 104 to the reaction chamber 102 which contains flux. In other words, in order to increase the size of the group III nitride crystal which is obtained, the first method additionally supplies the group III metal 104 when growing the group III nitride crystal.
The group III metal supply pipe 103 has a hole 105. The crystal growing apparatus further includes a pressure applying unit 106, an internal space 107 of the reaction chamber 101, a nitrogen supply pipe 108, a pressure control unit 109, a lower heater 110, and a side heater 111.
On the other hand, the second method may be categorized into a mixing method and a fusion method. The mixing method applies external pressure to a molten mixture supply pipe which contains a molten mixture of flux (Na) and group III metal (Ga), so as to additionally supply the molten mixture to a growth chamber which contains the flux. The fusion method supplies an intermetallic compound of flux (Na) and group III metal (Ga), and additionally supplies the group III metal by partial fusion of the intermetallic compound.
According to the first and second methods described above, the raw materials are additionally supplied during the crystal growth, thereby making it possible to grow larger crystals.
However, according to the first method, vapor of the flux (Na) concentrates at a low-temperature portion, causing the flux (Na) to adhere on the group III metal supply pipe 103 which has a low temperature. As a result, the hole 105 of the group III metal supply pipe 103 may be clogged by the adhered flux (Na). If the temperature of the group III metal supply pipe 103 is increased in order to prevent the flux (Na) from adhering thereon, the group III metal reacts with the material forming the group III metal supply pipe 103 in a case where the group III metal is Ga and the material forming the group III metal supply pipe 103 is stainless steel, for example. Consequently, the hole 105 of the group III metal supply pipe 103 is also clogged when such a reaction occurs between the group III metal and the material forming the group III metal supply pipe 103.
On the other hand, according to the mixing method of the second method, the flux exists within the molten mixture supply pipe. For this reason, the group III metal and the nitrogen react within the molten mixture supply pipe and generate a group III nitride, to thereby clog the molten mixture supply pipe.
According to the fusion method of the second method, if the intermetallic compound is mixed into the flux and partially fused, a rapid reaction occurs between the intermetallic compound and the nitrogen, to thereby deteriorate the crystal properties of the group III nitride which is obtained.
And, according to the mixing and fusion methods of the second method, the solubility of the nitrogen to the molten mixture is small, and the growth rate of the group III nitride crystal is low.

Methods of growing a group III nitride crystal


A method encodes a sequence of blocks of input bits to be transmitted over a wireless channel. Each block of input bits is converted to a codeword, and each codeword is mapped to multiple sub-blocks of complex numbers. Each sub-block is multiplied by a disambiguating spreading transform to obtain a sub-block of transformed symbols, which can be modulated and transmitted to a receiver, where each received block is demodulated to a block of complex numbers, which are partitioned into sub-blocks. The sub-block of complex numbers are converted to a set of likelihood ratios that correspond to decoded codewords. The input bits can be decoded unambiguously even if only one of the blocks of symbols corresponding to the block of input bits is received correctly.

Wireless Communications
Wireless communications devices allow a degree of convenience and mobility that wired devices cannot match. However, wireless communications systems are subject to problems that do not occur to the same degree for wired systems. Foremost among these problems is fading. Fading is the time-variation of channel conditions. A second problem is interference between multiple signals that concurrently use the same part of the frequency spectrum.
As the transmission rate of wireless communications continues to increase, the frequency selectivity of the wireless channel is a major issue. A 'frequency-selective' channel is one for which the propagation is a strong function of frequency within the bandwidth of the channel.
Orthogonal Frequency Division Multiplexing (OFDM)
One popular method to deal with frequency-selective channels is orthogonal frequency division multiplexing (OFDM). OFDM is used in wireless local area networks, as covered in the IEEE 802.11a, 802.11g, and 802.11n standards, as well as fixed wireless access systems, as covered in the IEEE 802.16 standards, and high mobility systems for high data rates, as covered in the IEEE 802.20 standards. Anticipated fourth generation cellular telephone systems are also expected to use OFDM.
The basic principle of OFDM is to partition a frequency-selective wide-band channel into a number of parallel, narrow-band sub-channels, also called 'sub-carriers', or 'tones'. Each sub-channel is frequency-nonselective, i.e., non-delay-dispersive. This principle is similar to traditional frequency division multiple access (FDMA). There are, however, major differences between OFDM and FDMA. In OFDM, the frequencies of the sub-channels are spaced as close as possible, without causing mutual interference, i.e., each sub-channel is located in the spectral nulls of the adjacent sub-channels. In OFDM, the conversion to parallel sub-channels can be done digitally, by means of a fast Fourier transform (FFT). In OFDM, a guard interval in the form of a 'cyclic prefix', ensures that even in the presence of a residual delay dispersion, the sub-channels do not interfere with each other, as long as the delay spread of the channel is shorter than the duration of the cyclic prefix.
A discrete-time effective channel model for a system using OFDM is given by the following system of equations. The symbol encoded by the OFDM system on the lth sub-channel at discrete time t is denoted by xl[t]. The corresponding received symbols yl[t] after being processed by the OFDM system are given byyl[t]=Hl[t]xl[t]+nl[t].  (1)
Here, Hl[t] is a random variable called the attenuation or 'fading' factor for the lth sub-channel at time t. The noise nl[t] is a zero-mean random variable chosen from a Gaussian distribution. The symbols xl[t] and yl[t], the attenuation factor Hl[t], and the noise nl[t] are all represented as complex numbers.
The 'equalization' of OFDM systems is simple. Because each sub-channel is effectively narrow-band, the signal received for this sub-channel needs only to be divided by the complex number Hl[t] representing the attenuation at this specific sub-carrier.
Models for Fading and Interference
Depending on the specific application, different probability distributions are appropriate for the random variables Hl[t]. If the variables Hl[t] are selected from a complex Gaussian distribution with zero mean, then the model is called a 'Rayleigh' fading model. Rayleigh fading models are very popular models for wireless channels.
If the Hl[t] for the same sub-carrier at neighboring discrete times are correlated, then the model is called a 'slow-fading' channel. If the Hl[t] for the same sub-carrier at neighboring discrete times are independent, then the model is called a 'fast-fading' channel.
A simplified model for interference is obtained using an 'erasure' model for the probability distribution of Hl[t]. In this model, each fading factor Hl[t] is independently selected to be one, with a probability 1-pe, and zero, with a probability pe. The zeros represent interference caused by other signals that occur with probability pe.
Lack of Frequency Diversity in OFDM
Unfortunately, each sub-channel in an OFDM system is effectively narrowband. Therefore, OFDM, by itself, does not give any frequency diversity when a sub-carrier is in a fading dip or an erasure. If Hl[t] has a small magnitude, then its signal-to-noise-ratio (SNR) is low, and the corresponding received symbol is decoded with a high probability of error.
This problem can be solved in several possible ways. First, if the instantaneous SNR for each sub-carrier is known at the transmitter, then adaptive modulation, in combination with appropriate codes, can ensure that the signaling rate for each specific sub-carrier is at an appropriate level that can be sustained without too many errors. Second, if the transmission of the data occurs over a time duration that is much longer than the coherence time of the channel, then appropriate codes combining symbols at the same sub-carrier but over different times can exploit the changes over time in the channel conditions. Third, error-correcting codes can be used across different sub-carriers at the same time. This very common approach is called 'coded' OFDM.
However, there are many practical situations where none of the above approaches is optimal, or even possible. The first approach requires instantaneous channel state information at the transmitter, which imposes a large feedback overhead, as well as a large modulation alphabet, which imposes hardware constraints. The second approach requires coding over a long time, which is not desirable in many cases, particularly when long delays cannot be tolerated. Furthermore, long period encoding may be impossible in situations where there is insufficient time diversity, such as in fixed wireless access. Encoding across frequency using an error-correcting code often requires the use of low code-rate codes in order to be effective. That means that an excessive number of redundant symbols are transmitted, decreasing the effective throughput on the channel.
MC-CDMA
For these reasons, another approach called 'multi-carrier code division multiple access' (MC-CDMA) can be used, see K. Fazel, "Performance of CDMA/OFDM for Mobile Communications Systems," ICUPC 1993, vol. 2, pp. 975-979, 1993, and S. Kaiser, "Trade-off Between Channel Coding and Spreading in Multi-carrier CDMA Systems," Proc. ISSSTA 1996, pp. 1366-1370, 1996. In that approach, a data block, on different sub-channel frequencies, is multiplied by a Walsh-Hadamard transform (WHT). This multiplication spreads the information for each symbol over all available tones. The number of symbols that are multiplied is the same as the number of tones, giving a code-rate of one, so that no redundancy is introduced. Because all symbols are transmitted on all tones simultaneously, the system fully exploits the frequency diversity in all channels. Even if some tones are in fading dips, the information from the 'good' tones is sufficient to allow reconstruction of the transmitted symbols, in most, but not all cases.
MC-CDMA can be used in ordinary OFDM systems or in coded OFDM systems. When used with coded OFDM systems, the idea is to reduce the redundancy needed in the error-correcting code.
FIG. 1 shows a prior art transmitter or 'encoder' 100 for a coded OFDM system using multi-carrier CDMA. Data bits 101 emitted by a source are encoded 110 using an error-correcting code, and thus redundant bits are added to make code words 102. The resulting code words 102 are mapped 120 into a block of complex symbols 103. In the MC-CDMA part of the transmitter, the resulting block of complex symbols are multiplied by a WHT matrix 130 to obtain an equal-length block of complex symbols 104. The resulting equal-length block of symbols is converted 140 into a continuous-time signal 105 in the OFDM part of the transmitter by adding a cyclic prefix and applying an inverse FFT.
The functions of the MC-CDMA part of the transmitter can be expressed as follows. The input at discrete time t is a data block of complex symbols {ul[t]}, and the number of sub-channels N is equal to some power of two. To obtain the block of complex symbols {xl[t]} that is sent to the inverse FFT, we multiply by the N×N WHT matrix WN:
                                          x            l                                          [            t            ]                          =                              ∑                          m              =              1                        N                                                                                W              lm              N                                                                                u                  m                                                                  [                  t                  ]                                            .                                                          (        2        )
Walsh-Hadamard Transform Matrices
WHT matrices can be constructed recursively as follows. The smallest version is a 2×2 matrix W2 of the form
                              W          2                =                              1                          2                                                                    (                                                                    1                                                        1                                                                                1                                                                              -                      1                                                                                )                        .                                              (        3        )
To construct a larger WHT matrix WN, where N=2B, one forms a Kronecker product of B 2×2 WHT matrices. Thus, the WHT matrix W4 is given by W4=W2{circle around (×)}W2, and W8=W2{circle around (×)}W2{circle around (×)}W2, and so on. The expression 'W2{circle around (×)}M' means that one expands every l in the matrix M into a sub-matrix W2, and every −l into a sub-matrix −W2. Thus, for example, the next two WHT matrices after W2 are
                                          W            4                    =                                    1              2                                                  (                                                                    1                                                        1                                                        1                                                        1                                                                                1                                                                              -                      1                                                                            1                                                                              -                      1                                                                                -                      1                                                                                -                      1                                                                            1                                                        1                                                                                -                      1                                                                            1                                                        1                                                                              -                      1                                                                                )                                                                                and                            (        4        )                                          W          8                =                              1                          8                                                                    (                                                                    1                                                        1                                                        1                                                        1                                                        1                                                        1                                                        1                                                        1                                                                                1                                                                              -                      1                                                                            1                                                                              -                      1                                                                            1                                                                              -                      1                                                                            1                                                                              -                      1                                                                                -                      1                                                                                -                      1                                                                            1                                                        1                                                                              -                      1                                                                                -                      1                                                                            1                                                        1                                                                                -                      1                                                                            1                                                        1                                                                              -                      1                                                                                -                      1                                                                            1                                                        1                                                                              -                      1                                                                                -                      1                                                                                -                      1                                                                                -                      1                                                                                -                      1                                                                            1                                                        1                                                        1                                                        1                                                                                -                      1                                                                            1                                                                              -                      1                                                                            1                                                        1                                                                              -                      1                                                                            1                                                                              -                      1                                                                                1                                                        1                                                                              -                      1                                                                                -                      1                                                                                -                      1                                                                                -                      1                                                                            1                                                        1                                                                                1                                                                              -                      1                                                                                -                      1                                                                            1                                                                              -                      1                                                                            1                                                        1                                                                              -                      1                                                                                )                        .                                              (        5        )
Factor Graph Representations of Fast Walsh-Hadamard Transforms
Naively, a multiplication using a WHT matrix as in equation (2) appears to require approximately N2 computations. However, the multiplication can be done in a 'fast' way requiring on the order of N log2 N operations. The 'fast' Walsh-Hadamard transform is analogous to a FFT.
To explain the fast WHT, it is easiest to use a 'factor graph'. For a detailed explanation of factor graphs, see F. R. Kschischang, B. J. Frey, and H-A. Loeliger, "Factor Graphs and the Sum-Product Algorithm," IEEE Transactions on Information Theory, vol. 47, pp. 498-519, February 2001. There are several essentially equivalent forms of factor graphs. The following discussion is based on so-called 'normal' factor graphs, as described by G. D. Forney, Jr., "Codes on Graphs: Normal Realizations," IEEE Transactions on Information Theory, vol. 47, pp. 520-548, February, 2001.
A normal factor graph is drawn as a collection of connected vertices. The connections between the vertices, which are drawn as lines, represent 'variables'. The vertices, which are drawn as squares and referred to as 'factor nodes' represent constraints placed on the variables that connect to that factor node. In a 'normal' factor graph, each variable can be connected to either one or two factor nodes, and each factor node can connect to one or more variables.
The factor graph for a fast Walsh-Hadamard transform can be constructed using 'butterfly' factor nodes, as described by J. S. Yedidia, "Sparse Factor Graph Representations of Reed-Solomon and Related Codes," MERL TR2003-135, Mitsubishi Electric Research Laboratories, Cambridge, Mass., December, 2003, and Proceedings of the 2003 DIMACS Workshop on Algebraic Coding Theory, September 2003. A butterfly factor node has two 'input' variables entering the node from the left, and two 'output' variables exiting the node from the right.
In a butterfly factor node, there are two constraints on the variables. The two input variables are denoted by x1 and x2, and the two output variables are denoted by y1 and y2. The two constraints are written asy1=Ax1+Bx2  (6)y2=Cx1+Dx2  (7)where A, B, C, and D are constants. The choice of the four constants in these equations defines the specific form of a butterfly factor node.
As shown in FIG. 2, a prior art butterfly factor node 201 is drawn as a square with the four constraint constants (A, B, C, D) placed inside the node, and with the input variables 211 represented by connected lines coming into the square from the left, and the output variables 212 represented by connected lines coming out of the square to the right. The prototypical butterfly factor node 201 corresponds to equations (6) and (7) above.
FIG. 3 shows a prior art factor graph 300 for a fast Walsh-Hadamard transform of size N=8. The factor graphs for the fast Walsh-Hadamard transforms is constructed using butterfly factor nodes 301 where the constants are given by A=B=C=1/√{square root over (2)}, and D=−1/√{square root over (2)}. The factors are connected in a regular way that is identical to the wiring in FFTs. The input variables 302 on the left are the variables um, the output variables 303 on the right are the variables xl, and the factor graph implements the relationship
                              x          l                =                              ∑                          m              =              1                        N                                                                                W              lm              N                                                                  u                m                            .                                                          (        8        )
OFDM Receivers
FIG. 4 shows a conventional receiver (decoder) 400 for a prior art coded OFDM system that uses MC-CDMA. The receiver 400 takes the received signal 401, and then in step 410, performs an FFT and removes the cyclic prefix to obtain a block of corrupted complex symbols 402. Then, an inverse WHT is performed 420 to recover complex symbols 403. Finally, complex symbols are decoded 430 using an error-correcting code to obtain a reconstruction 404 of the original transmitted bits.
There are two main problems in the decoders for systems that use MC-CDMA. One is related to the performance when simplified decoding methods are used. The simplest decoding approach is to multiply the received signal with the inverse of the Walsh-Hadamard matrix after equalization of each OFDM tone, and before demodulation and decoding. Unfortunately, this decoding approach leads to noise enhancement. The noise from the 'bad' tones with a low SNR, which are amplified in the equalization process, is distributed over all tones. This problem can in principle be solved using maximum-likelihood or optimal detection for the inverse WHT. However, processing-time considerations limit maximum-likelihood detection to very small Walsh-Hadamard matrices.
The second problem with MC-CDMA systems using Walsh-Hadamard transforms is related to the performance of decoding in the presence of many sub-channel 'erasures' due to bad SNRs, as may be created by fading dips or interference on channels. Unfortunately, because of the form of the WHT matrix, several different bit combinations can lead to the same complex symbol being transmitted on a single tone. As a simple example, suppose that a 2×2 WHT matrix is used, and the possible input symbols are 1.0 and −1.0. The first output symbol after a Walsh-Hadamard transform is the sum of the two inputs divided by √{square root over (2)}. If the first output symbol is received as a 0.0, then that symbol could have arisen because the first input was a 1.0 and the second input was a −1.0, or vice versa. Naturally, the combination of the information of all tones is sufficient for a demodulation. However, if some tones are erased, then the reconstruction 404 can be ambiguous when a Walsh-Hadamard transform is used. Therefore, it is desired to use a different spreading transform for which an unambiguous choice of the reconstruction can be made so long as at least one output symbol is received correctly.
Asymmetrical Spreading Transforms
For the particular case of a 2×2 spreading matrix, it is known that a considerable performance improvement can be realized by using an asymmetrical spreading matrix of the form
  U  =            (                                    2                                1                                                              -              1                                            2                              )        .  This spreading matrix enforces a transmit symbol constellation that enables reconstruction even if one of the two tones that carry the information about one bit is erased.
A similar idea is described for a transform that spreads symbols across time or space with different transmitting antennas using 'permutation codes', S. Tavildar and P. Viswanath, "Permutation Codes: Achieving the Diversity-Multiplexing Tradeoff", International Symposium on Information Theory (ISIT), Jun. 27, 2004.
However, the prior art transforms are only described for very small N. The only explicit constructions are for cases when the number of sub-carriers is two. It is well known that larger values of N are necessary to obtain a diversity gain that is possible by spreading out a symbol over many different sub-carriers.
To summarize, prior art methods exist for spreading symbols across multiple sub-carriers using a WHT. All of those methods suffer from two problems. There is ambiguity during the decoding when some of the sub-carriers are in deep fades. Noise from faded sub-carriers is amplified when simple decoding methods are used. Some prior art methods spread a symbol across two sub-carriers in a way that can be disambiguated, even if one of the sub-carriers is erased. However, there are no prior art methods for spreading symbols across more than two channels without suffering from the problem of ambiguity when some of the sub-carriers are in deep fades.
Therefore, it is desired to provide a method for spreading symbols to be transmitted over more than two sub-carriers subject to fading, interference, and noise, so that it is possible to reconstruct the symbols unambiguously symbols for MC-CDMA in OFDM systems. There is a similar need for spreading symbols across time-division multiple access (TDMA) or across multiple receive antenna and multiple transmit antenna (MIMO) systems.
In general, it is desired to provide a signal encoding method that is effective for any channel model that can be written in a form similar to that given in equation (1), where the indices l and t represent alternative sub-channels over which symbols are transmitted.

Unambiguously encoding and decoding signals for wireless channels

Mitsubishi Electric Research Laboratories, Inc.


A method, apparatus and system related to zero-configuration remote control of device(s) coupled to a networked media device through a client side device communicatively coupled with the networked media device are disclosed. In one embodiment, a method of a client device includes determining that an internet protocol address and a port from an unannounced device is associated with a networked media device. The client device constrains an executable environment in a security sandbox. Then, the client device executes a sandboxed application in the executable environment using a processor and a memory. Next, the client device automatically instantiates a connection between the sandboxed application and the unannounced device associated with the networked media device based on the determination that the internet protocol address of the port from the unannounced device is associated with the networked media device. The unannounced device may utilize a web services interface and/or an infrared remote control interface. The networked media device may utilize an InfraRed (IR) blaster to associate with the unannounced device instead of the internet protocol address and the port when the unannounced device utilizes an infrared remote control interface.

A communication may be established between an unannounced device (e.g., a set-top box (STB) that functions as a tuner for a content distribution service, a stereo, a HDMI-CEC protocol device, an AV-link, and/or a media player) and a networked media device (e.g., a television, a projection device, a multi-dimensional visual emersion system, a console). For example, a user of the networked media device may read a manual to understand a protocol to configure the unannounced device to operate with a networked media device (the media device registered in a communication network). The user may configure the unannounced device to communicate with the networked media device through a protocol (e.g., an internet protocol, an InfraRed (IR) protocol, through a HDMI-CEC protocol). However, a client device (e.g., a client device such as an Apple iPhone®, Google Nexus®, an Apple iPad®, a Samsung Galaxy phone, etc.) accessing the networked media device through a local area network may not be able to communicate with the unannounced device. This can result in inconvenience for a user of the client device because there may be no centralization of control mechanisms for unannounced devices through the client device.

Remotely control devices over a network without authentication or registration


A high speed electrical connector assembly (1) comprises a female connector (2) and a male connector (3) assembled together to be electrical connection to a printed circuit board (9). A plurality of differential pairs of signal contact (51) and a plurality pairs of ground contact (53) with the pairs of signal contacts (51) arranged therebetween are secured in the connector assembly (1). Each of the differential pairs of signal contact (51) has a first contact engaging portion (511) which is accessible from the female connector (2), and includes a second contact engaging portion (513), extending away from the first engaging portion (511) and accessible from the male connector (3). A shielding bus (10) is electrically interconnecting to at least one of the ground contact (53), and includes a shroud portion substantially enclosing the median portion of the pair of signal contacts (51).

1. Field of the Invention
The present invention relates to an electrical connector, and more particularly to a high speed electrical connector for coupling an electrical device to a backplane and featured with a shielding system.
2. Description of the Related Art
U.S. Pat. No. 6,071,150 issued to Tang et al. on Jun. 6, 2000, discloses an extender (10) including a male section (12) and a female section (14) assembled together to be coupled between a female connector on a backplane in the computer and a male connector on a hard disk drive for establishing signal transmission between the hard disk drive and the backplane through the interconnections of such male and female sections. Specifically, the female section defines a female interface adapted for mating with the male connector from the hard disk drive, the male section defines an opposite male interface adapted to mate with the female connector from the backplane of the computer, and a plurality of contacts are configured to extend from the female interface towards the male interface for electrically connecting the female section with the male section. This configuration typically enables the female or male interface to supply one voltage for the male connector of the hard disk drive, or the female connector of the backplane.
U.S. Pat. No. 6,918,774 issued to Wu on Jul. 19, 2005 discloses an electrical connector (1) includes a dielectric housing (2) including front and rear housing portions (20, 22) each defining a number of juxtaposed channels (202) therein and an intermediate housing portion (24) interconnecting the front housing portion with the rear housing portion. A number of elongate circuit boards (3) are side by side retained in the housing along a second direction perpendicular to the first direction. The circuit boards include front and rear mating edges (30, 32) respectively received in the channels of the front and the rear housing portions for mating with complementary components.
U.S. Pat. No. 6,663,434 issued to Wu on Dec. 16, 2003 discloses an extender (10) includes a female portion (12) and a male portion (14) adapted to be back-to-back assembled. The female portion comprises a first housing (16) defining two slots (28) and a plurality of first contacts (18, 19). A plurality of first passageways (30) is defined in the first housing and communicates with the slots. The first contacts are retained into the first passageways. The male portion comprises a second housing (40) having a pair of tongues (46) and a plurality of second contacts (41). The tongues define a plurality of positioning slits (52, 53) for receiving the second contacts. Each of the first contacts is aligned and cooperated with a corresponding second contact to form a transmission path. Two pairs of latch devices (35, 60) are provided on opposite ends of the female portion and male portion for fastening each other.
In the past, the electrical device, such as a hard disk data storage, and a backplane on which the device is electrically interconnected, generally carry the same voltage, i.e. both are operated under the substantially identical working environment. However, when data transmission rate becomes faster and faster, their working environments have to change also so as to meet the requirements.
The present problem the users confront, is that the female or male interface substantially requires an electronic device of a first predetermined voltage to be equipped therewith, while the electronic component available for the users has a second predetermined voltage. In other words, the conventional configuration has no capability to provide a flexible connection to different types of electronic devices, which may require voltages of different amounts.
In the previously filed '814 application, applicant initiated a novel design such that a mating interface of an extender is supplied two different working voltages, and which indeed meets the current requirements.
In addition, when the requirement regarding to the data transmission rate becomes higher and higher, differential pair of signal contacts are used, and once the differential pair of contacts are used, grounding or shielding of the differential pair of contacts becomes a new challenge to resolve. When signal pins of different differential pairs become coupled with one another, the signal pins exhibit cross talk. Cross talk increases the interference, noise and jitter within the circuit board, connector and system. Increasing the distance between signal pins of separate differential pairs typically decreases the effects of interference, noise and jitter. Increasing the distance between differential pairs typically requires a larger connector. However, electrical and electronic applications today require a large number of differential pairs to be packaged in a small space. Many systems require as small a connector as possible to make efficient use of internal space. None of the above described prior arts consider the use of differential pair of contacts. In addition, a grounding arrangement between the first and second mating interfaces, and a circuit substrate on which the extender is mounted is not provided as well.

High speed electrical connector assembly with shieldding system


Methods of fabricating semiconductor devices and structures thereof are disclosed. In a preferred embodiment, a method of manufacturing a semiconductor device includes providing a semiconductor wafer, forming a first insulating material over the semiconductor wafer, and forming a plurality of first features and a plurality of second features in the first insulating material. The plurality of first features is removed, leaving an unfilled pattern in the first insulating material. The unfilled pattern in the first insulating material is filled with a second insulating material.

Semiconductor devices are used in a variety of electronic applications, such as personal computers, cell phones, digital cameras, and other electronic equipment, as examples. Semiconductor devices are typically fabricated by sequentially depositing insulating or dielectric layers, conductive layers, and semiconductive layers of material over a semiconductor substrate, and patterning the various layers using lithography and etch processes to form circuit components and elements thereon.
Chemical-mechanical polishing (CMP) processes are often used to planarize material layers of semiconductor devices. In many integrated circuit designs, material layers are planarized before depositing subsequent material layers. CMP processes are typically used for global planarization of a semiconductor wafer, and to remove excess material from over certain topographical features, e.g., after an etch process or deposition process, for example. In a CMP process, elevated features of a wafer are selectively removed, e.g., material from high elevation features is removed more rapidly than material at lower elevations, resulting in reduced topography. The process is referred to as "chemical-mechanical polishing" because material is removed from the wafer by mechanical polishing, assisted by chemical action.
It is important for etch processes and CMP processes to have a uniform effect on semiconductor devices during the fabrication process in some designs, so that the various devices formed thereon have uniform electrical parameters. A planar surface is also important in order to achieve depth of focus (DOF) for lithography processes, for example.
Some semiconductor device designs have regions that are densely populated with features and other regions that are absent features or are less densely populated with features. A CMP process may affect the more densely populated regions differently than the less densely populated regions, resulting in an uneven planarization process. For example, less densely populated regions may be planarized more than more densely populated regions. Dishing of material layers may also occur in less densely populated regions, as another example. Uneven planarization and dishing may present problems later in the manufacturing process as subsequent material layers are deposited and processed over the wafer.
Thus, what are needed in the art are improved methods of fabricating semiconductor devices and structures thereof.


A classifying method according to an eye form considers the eye form feature as an important factor, to provide an eye cosmetic treatment method for appropriately and quickly making up the eye so that the eye balances and looks large and attractive according to the type categorized by the classifying method. A makeup tool is devised by integrating an eye form feature analyzing method with a form shaping method by markup. An eye form classifying method uses as indexes, three forms, namely, the eye frame form showing the shape of the eye contour, the eye form showing the three-dimensional shape of the eye, and the angle form of the inner corner and outer edge, the eye forms are classified. The eye forms are classified by comparing the eye form with the eye form of a reference balanced eye.

In recent years, interest in an eye makeup method, i.e., an eye cosmetic treatment method, has been growing, and information on cosmetic treatment methods, cosmetic items, and makeup tools is introduced in a variety of beauty magazines or general magazines, and the like. However, the conventionally proposed eye makeup methods are not designed to extract only eyes and apply makeup only to eyes while understanding eye features. Instead, they simply pay attention to eyes in terms of a balance with an entire face. Such a cosmetic treatment method that pays attention to eyes in entire face is disclosed in, for instance, Japanese Patent Application Laid-Open No. 10-289322, and Japanese Patent Application Laid-Open No. 2000-14661.
Although it is a vital factor in achieving an effect of makeup, and many are longing to have eyes having the form features of being large and bright, the information viewed from the aspect of eye forms is extremely little available. Eye features such as single-edged eyelid, double-edged eyelid, downward slanting eyes, and the like are roughly identified, these features being extracted as negative features, and makeup methods for adjusting them are simply presented case by case.
Classifying eyes based on the form features is imperative in understanding eye features of individual persons and in deciding a makeup treatment according to the features. As the situation stands now, however, no method of picking up more detailed elements and systematically classifying them has been presented although there is some classification of upper lids that is designed to describe racial features in anthropology. Furthermore, no classification of the eye form features that could be associated with eye makeup methods has been proposed. Moreover, with makeup methods on case-by-case basis, it would be difficult to find a way to make individually different eyes look attractive. In fact, trying and failing, the methods simply give eye makeup adapted to individual persons who fix their faces, which is an inefficient process of trial and error. In terms of improvement of techniques of beauty technicians, as neither systematized analyzing method nor makeup method is available, experience is an indispensable factor.

Eye form classifying method, form classification map, and eye cosmetic treatment method


The present invention provides high strength magnesium-based alloys which are composed a fine crystalline structure, the alloys having a composition represented by the general formula (I) Mg.sub.a X.sub.b ; (II) Mg.sub.a X.sub.c M.sub.d, (III) Mg.sub.a X.sub.c Ln.sub.e ; or (IV) Mg.sub.a X.sub.c M.sub.d Ln.sub.e (wherein X is one or more elements selected from the group consisting of Cu, Ni, Sn and Zn; M is one or more elements selected from the group consisting of Al, Si and Ca; Ln is one or more elements selected from the group consisting of Y, La, Ce, Nd and Sm or a misch metal of rare earth elements; and a, b, c, d and e are atomic percentages falling within the following ranges: 40.ltoreq.a.ltoreq.95, 5.ltoreq.b.ltoreq.60, 1.ltoreq.c.ltoreq.35, 1 .ltoreq.d.ltoreq.25 and 3.ltoreq.e.ltoreq.25). Since the magnesium-based alloys have a superior combination of properties of high hardness, high strength and good processability, they are very useful in various industrial applications.

1. Field of the Invention
The present invention relates to magnesium-based alloys which have a superior combination of high hardness and high strength and are useful in various industrial applications.
2. Description of the Prior Art
As conventional magnesium-based alloys, there have been known Mg-Al, Mg-Al-Zn, Mg-Th-Zr, Mg-Th-Zn-Zr, Mg-Zn-Zr, Mg-Zn-Zr-RE (rare earth element), etc. and these known alloys have been extensively used in a wide variety of applications, for example, as light-weight structural component materials for aircrafts and automobiles or the like, cell materials and sacrificial anode materials, according to their properties.
However, conventional magnesium-based alloys, as set forth above, have a low hardness and strength and are also poor in corrosion resistance.


A transparent white ink composition is formulated to brighten, lighten and or dilute full-tone primary inkjet colors: cyan; magenta; yellow and black, eliminating the need for ‘light ink’ primary color inks. The transparent white ink is jetted concurrently with reduced amounts of full-tone inks in lighter tonal areas conventionally supported by ‘light ink’ primary inks. Printing ‘light ink’ primary colors using a transparent white ink composition may reduce the number of print channels needed to print all four primary colors and the four ‘light ink’ primary colors. Embodiments of the transparent white ink composition may be solvent- or water-based, drying by evaporation of the carrier fluid. Other embodiments may be radiation-curable ink compositions. An inkjet printer includes print carriage and print head assemblies configured for jetting a primary color ink and the transparent white ink in the same pass in correct proportions to achieve a desired effect.

1. Field of the Invention
In general the invention relates to the field of inkjet printing. More particularly, the invention relates to a method and apparatus for controlling lightness in colored inkjet inks by means of a transparent white ink composition.
2. Background Information
Conventionally, in color inkjet printing, the printer must print several of the printer's dots for each pixel of an image. Inkjet printers may print only a few colors: for example, cyan, magenta, yellow and black. Rendering each pixel of an image into various colors, shades, and intensities requires that the image be dithered, meaning that the printer creates patterns of dots in multiple colors in order to simulate the color of each pixel in the image. Additionally, some inkjet printers also print lighter values of the same four colors. Thus, conventional inkjet printers now typically use eight colors: cyan, light cyan, magenta, light magenta yellow, light yellow, black and light black. Currently, an inkjet printer's ability to output these eight different colors requires an inkjet set that includes at least eight separate inks, with a separate channel devoted to each ink. Thus, modern inkjet printers must have at least eight print channels. The cost to own and operate a conventional inkjet printer reflects the manufacturing cost of providing a separate channel for each of the colors.
Additionally, large-format or grand-format UV inkjet printers that are capable of printing with UV-curable white ink are becoming increasingly common. The white-ink printing capability, requiring at least one additional print channel, adds to the design complexity and the manufacturing cost of such inkjet printers.
Inkjet printing methods wherein inkjet inks are mixed with colorless liquids just prior to jetting in order to control color density are known. Additionally, it is known to produce a white inkjet ink having improved dispersion stability by mixing a white inkjet ink having a predetermined refractive index with at least one colorless liquid, such as a dispersant, a photo-initiator or a solvent.

Method and apparatus for controlling lightness in colored inkjet inks by means of a transparent white ink composition


This invention relates to methods and apparatus for interfacing between computer channels and a Broadband Integrated Services Digital Network (B-ISDN) in order to allow such channels to communicate with a large number of other channels over the long distances and large bandwidth provided by B-ISDN. In a terminal adapter, channel addresses are translated into network addresses and channel format data is converted into B-ISDN format data in order to allow data messages between channels to be transmitted over the B-ISDN network.

Computer channels are the arrangements used by some computers such as IBM and IBM clone computers to communicate with other computers, peripheral equipment such as storage devices, and input/output devices such as terminals and printers. One such set of channels is defined by a standard known as the FIPS 60 standard defined by the National Bureau of Standards and operates at speeds of 3, 4.5, and eventually 6 megabytes per second. In the past, such high speed channels have been connected to low speed data networks. However, with the introduction and standardization of broadband integrated services digital network (B-ISDN) facilities such as those defined by CCITT and the IEEE 802.6 standard for metropolitan area networks, it becomes possible to transmit data at data channel rates over a data network. The B-ISDN network is described in "Broadband Aspects of ISDN-T1S1 Technical Subcommittee", Document T1S1.1/88-333, published by American National Standards Institute (1988), and the 802.6 network is described in "Project 802-Local and Metropolitan Area Networks Proposed Standard", prepared by the IEEE 802.6 Working Group, Jun. 26, 1988. A channel addresses a maximum total of 256 subchannel addresses and each address terminates on a device or software subsystem in a host computer. Arrangements exist for interconnecting 8 or 16 host channels using a Multisystem Channel Communication Unit (MCCU). The subchannel addresses are distributed among the potential destinations in accordance with information stored in a read only memory, initialized all installation time, defined within the MCCU. Thus in a case of a MCCU serving 8 channels, each channel may communicate with any other channel or device over 32 different subchannel addresses. With the use of MCCU, each sending channel sends data on a particular address within a range of addresses dedicated to that sending channel. This address is converted in the MCCU to a corresponding address for addressing the desired channels and, in some cases, an associated device. A problem with this type of unit is that it can only be used for accessing other channels or devices within typically 400 feet of the MCCU. The channels are therefore limited to being within 800 feet of each other. The requirement to pass state information from each channel for every subchannel address to each interacting channel on a given subchannel address, sufficiently rapidly to minimize the occurrence of "glare", wherein two ends of a communication between subchannels both generate "read" or "write" commands simultaneously, with small effect on performance due to this overhead, restricts this distance in the prior art. The current limitations include an overall throughput limitation to the bandwidth of 2 or 4 busses within the MCCU, and a limit of only 2 or 4 simultaneous conversations are possible between the 8 or 16 interconnected channels.
Other disadvantages of the MCCU are that it is not user programmable, i.e., it is set up in the factory using firmware to define the particular configuration for which it is being used. The MCCU arrangement limits each connected channel to a single communication at any one time and further limits the entire system to two or four simultaneous communications because of the presence of a shared bus within the MCCU. A channel has the ability to send to multiple destinations simultaneously; however, since the MCCU is a non-buffered device, it does not allow the channel to transmit until a data path is available, so that multiple transfers from over the same physical path and a channel cannot take place in the prior art.
In another arrangement in the prior art for communicating over long distress, computer channels are interconnected over a 1.5 megabit/second digital carrier facility. This arrangement is limited in bandwidth to the bandwidth provided by the digital carrier and is limited to connecting only the two channels at the endpoints of the carrier facility. There is therefore no provision for switching data blocks concurrently to more than one other channel.
While such high speed computer channels can be used advantageously for communications between two computers, or computers to devices or, in some cases, to a small group of such devices, the availability of B-ISDN facilities makes it possible for computers to communicate with a large number of other computers over a broadband network at channel speeds. However, there are no arrangements in the prior art which permit such connection. Further, a great deal of computer software is written on the assumption that computer channels communicate directly with other computer channels. The "handshake" arrangement for establishing connections between computer channels assumes that another channel is connected.
A problem of the prior art therefore is that there are no economically attractive arrangements whereby computer channels can communicate at high speeds with a large number of other computers or devices.

Channel adapter for broadband communications at channel speeds


A vehicular screen antenna includes a conductor extending on a dielectric, such as a window. The conductor is configured as a loop having entry and exit segments, the loop being positioned generally centrally on the dielectric. The entry and exit segments extend proximate each other from the loop towards a first edge of the dielectric and are oriented on the dielectric so as to extend generally vertically when the dielectric is fitted to a vehicle.

The present invention relates to a vehicular antenna system and, more particularly, to a system that includes a configuration for a loop antenna which enhances reception performance.
Antennas integrated into parts of a vehicle are known. One approach is to use the de-misting heater grid on the rear screen as part of the antenna; see Japanese Patent Application No. 48-132005. Such an arrangement may be used with a separate element for AM reception; see EP Patent Application No. 0 155 647.
Some vehicles provide a suitable dielectric surface onto which a dedicated antenna element pattern can be formed. One example is the rear quarter window on a station wagon (estate car). Such windows are fixed, which allows the printing of a suitable antenna pattern. For example, the use of separate patterns to provide FM and AM radio reception was proposed in U.S. Pat. No. 3,771,159. Combining a pattern on a side window with elements on other windows to improve pattern coverage was proposed in EP Application No. 0 854 533.
A major problem with implementation of an antenna element on a rear quarter window of a vehicle is polarisation. Often the signal feedline needs to connect to the bottom of the window because of space limitations at the top and sides of the window frame. This means that the primary antenna currents are extending vertically, and there then exists correspondingly less horizontal polarisation ("horizontal polarisation" here signifying the horizontally-polarized component of the antenna signal). This causes problems for markets where broadcast signals are predominantly horizontally-polarised.

Integrated loop antenna for vehicular applications