The present invention relates to a key recovery process used for strong encryption of a message sent by an entity, which message is either to be stored locally or transmitted to another entity, the reading of a message requiring a decryption key which can be reconstructed at least by a trusted third party for key recovery, while added to the message are a compensation field and a compulsory control field which itself comprises at least one key recovery field for allowing at least one trusted third party to supply the decryption keys that enable the encrypted message to be read. This key recovery process is remarkable in that the compulsory control field also comprises, in unencrypted form, the current date as well as the agreement number of the encryption hardware/software and, encrypted under a daily intermediate key, the dialogue key. This key recovery field also comprises, first of all, the identifier of the appropriate trusted third party for key recovery, as a function of the application type, followed by a dialogue key encrypted under the public key or said trusted third party, and lastly, encrypted under the public key of said trusted third party, the serial number of the approved hardware/software and optionally the identifier of the entity and its manager, a working key being used to calculate the daily intermediate key and the period of validity of said working key. Finally, and equally remarkably, during the period of validity of the working key, said working key makes it possible, with only the compulsory control field having been supplied, to calculate in advance for the time period for which the eavesdropping has been authorized, by means of a prescribed formula, daily intermediate keys used to decrypt the dialogue keys, which are themselves used to calculate, from the compensation field and the compulsory control field, the random keys for decrypting the messages.

The present invention relates to a key recovery process used for strong encryption of a message sent by an entity, which message is either to be stored locally or transmitted to another entity, the reading of a message requiring a decryption key supplied to at least one trusted third party for key recovery, while the message comprises a compulsory control field which itself comprises a key recovery field for allowing a trusted third party to supply the decryption information that enables the encrypted message to be read.
First of all, it is noted that it is conventionally accepted that an encryption is considered to be strong when its decryption cannot be achieved within a reasonable amount of time without using the key.
Generally, the constant progress in the computerization field results in an increasingly immediate need when it comes to the protection of information. At present, computer security is an integral part of the thorny problems to be solved in this field. Thus, among other things, a problem arises when it is desirable to use encryption techniques to effectively protect sensitive information. In effect, in many countries, the dissemination of encrypted information through public networks is subject to authorization on a case-by-case basis, whereas the need to use such techniques is genuinely felt. The current tendency of international governmental authorities, however, is to authorize anyone to use strong encryption. In exchange for this authorization, the national authorities intend to retain the right of inspection, that is to have the capability to decrypt such communications.
With this type of technique, the stored or transmitted message can only be decrypted when the decryption key used is known. The specific object or technical problem in this case is to make the decryption key known to a predetermined key recovery authority, an authority hereinafter called a xe2x80x9ctrusted third partyxe2x80x9d for key recovery. Two techniques are generally used for this purpose.
The first technique consists of depositing a long-term decryption key which will be used to decrypt the working keys or decryption keys. Decryption hardware or software (hereinafter, for the sake of simplification and conciseness, indicated by xe2x80x9cdecryption hardware/softwarexe2x80x9d) then in turn uses this key to decrypt the decryption keys of a message, and thus any person wishing to decrypt the message must possess the copy of this key. This technique has proven effective and practical, for example within a single country, but has serious drawbacks relative to security when the communication is international and/or when an authority of one of the countries in question wishes to eavesdrop on and understand a message sent in one of the countries in question by a person under suspicion. In effect, one country""s trusted third party for key recovery is obligated to request another country""s trusted third party for key recovery, or the person possessing the copy of the key, [to supply it to it] in order to be able to decrypt the message. In the case where the latter agrees, which is a first restriction, on one hand the eavesdropping is xe2x80x9cgrantedxe2x80x9d to the other country""s trusted third party for key recovery when this type of intervention is supposed to be discreet and even confidential, and on the other hand, a significant time loss is inevitably caused in obtaining the copy of the key, which is completely inopportune since the message must be understood quickly when it is desirable to act fast with regard to the suspected person before the latter can escape or disappear. Therefore, this technique has substantial limitations for use at an international level due to the counterpart required by the international governmental authorities in authorizing this type of communication, unless the governments involved subscribe to reciprocity agreements, which in this field is not always, in fact rarely, desirable.
The second technique consists not of leaving a long-term decryption key but of allowing the trusted third party for key recovery to decrypt of the decryption key, and hence the encryption key of the message, whether this key is an asymmetric key or a symmetric key. For this purpose, two supplementary fields are added into the message, hereinafter called a compensation field and a compulsory control field, which itself comprises, among other information, at least one field intended for the recovery of the key by an authorized key keeper, hereinafter called a xe2x80x9ctrusted third partyxe2x80x9d for key recovery. Thus, in the particular case where a saved encrypted message is stored locally, for example on a disk, only one trusted third party for key recovery is involved, and therefore only one key recovery field is necessary. On the other hand, in the more general case of the transmission of a message between two users, or more generally between two communicating entities, two key recovery fields are necessary, since two trusted third parties for key recovery are involved, that of the country of the sender of the message and that of the country of the recipient of the message. Thus, an international conversation between two interlocutors of country A and country B, respectively, can be eavesdropped on, if this eavesdropping is authorized, by the appropriate intercepting authorities of country A and country B, respectively, without ever being subject to eavesdropping by the authorities of any other country. Consequently, when an eavesdropping is legally authorized, the first key recovery field of the compulsory control field allows eavesdropping by the approved authority of country A, while the second key recovery field allows eavesdropping by the approved authority of country B. These two approved authorities can either be national authorities based in the countries where the communicating entities are physically located, or national authorities of the same nationality as that of the communicating entities. In fact, in order to allow the decryption, one of these two key recovery fields present in the message is first delivered to a trusted third party for key recovery, then the decryption key is delivered by this trusted third party to the national authority, thus allowing it to decrypt the message in its entirety. Currently, it is expected for each country to approve a certain number of trusted third parties for key recovery who are nationals, each of whom is preferably specific to one field, and thus it is the trusted third party approved by a governmental authority that controls and allows the decryption and not the governmental authority directly. A technique of this type is described in the brochure entitled xe2x80x9cCommercial Key Escrow (CKE, a trademark of Trusted Information Systems, Inc.): The Path to Global Information Security.xe2x80x9d This second technique, however, also has a certain number of drawbacks. A first serious drawback is inherent in the fact that it is impossible to notice, in any simple way, that an attempted fraud has been perpetrated by modifying the compulsory control field or modifying the decryption hardware/software. Moreover, this technique does not make it possible to supply in advance daily decryption keys that are usable within, and only within, a predetermined time period, which is a second notable drawback relative to security. Finally, another drawback exists in the fact that the communicating entities are not identified, which does not make it possible to easily distinguish between legal or illegal eavesdropping.
The object of the present invention is to eliminate the various drawbacks of the different known techniques of the prior art, and to propose a key recovery process that is effective and easy to use, which makes it possible to detect any modification, however minimal, of the compulsory control field, and which allows the provision, even in advance, of daily decryption keys usable only within a predetermined time period.
FIGS. 1 and 2, illustrate the steps of the key recovery process used for strong encryption of a message (M) according to the present invention. Message (M) is sent by a sending entity (SE) (step 100), wherein the message is either to be stored locally or transmitted to a receiving entity (RE) (step 200). The reading of the message (step 600) requires a decryption key (DK) which can be reconstructed by at least one trusted third party (TTP) for key recovery (step 500). Each trusted party for key recovery is assigned an identifier (Id) and a public key (PK) (step 400). The process of key recovery further includes the steps of forming the message with a compensation field (CF) and a compulsory control field (CCF) (step 130), wherein the compulsory control field (CCF) includes a compulsory field comprising at least one key recovery field (KRF) for allowing the at least one trusted third party to supply the decryption key (DK) that enables the encrypted message (M) to be read (step 110). The compulsory control field (CCF) further comprises, in unencrypted form, a current date (D), an agreement number (AN) for encryption hardware/software and a dialogue key (DiK) encrypted under a daily intermediate key (IK) (step 120).
For this purpose, the key recovery process used for strong encryption of messages (M) mentioned in the preamble is remarkable in that the compulsory control field (CCF) also comprises, in unencrypted form, the current date (D) and the agreement number (AN) of the decryption hardware/software, as well as a dialogue (DIK) key encrypted under a daily intermediate key (IK), which intermediate key (IK) is a key calculated from certain elements of the compulsory control field (CCF) according to a formula that is explained below.
As used herein, the term xe2x80x9cstrongxe2x80x9d relates to ciphering and xe2x80x9cstrong encryptionxe2x80x9d means each message is encrypted in a way which tenaciously protects against a fraud.
Thus, according to the concept of the invention and as a result of the technique used, which will be described below, the modification, subsequent to its generation, of the compulsory control field (CCF) correctly generated by the sender renders decryption by the recipient impossible. In fact, an alteration of certain data of the compulsory control field (CCF) for the purpose of preventing the recovery of the decryption key (DK) of the message (M) by any of the trusted third parties makes it impossible to decrypt the message (M). Moreover, the agreement number (AN) of the decryption hardware/software allows the national authority authorizing the trusted third parties (TTP) for key recovery to be given the decryption keys (DK), first of all, to identify the hardware/software to be used for decrypting the message (M). Finally, the current date (D) makes it possible to ensure that the message (M) to be decrypted is transmitted within the correct time period, an incorrect date being detected automatically and immediately without even having to involve the trusted third party (TTP) for key recovery, but also and above all, it is the very foundation of the technique, making it possible to provide decryption keys (DK) in advance as explained below.
According to another characteristic specific to the present invention, the key recovery process is remarkable in that each key recovery field (KRK) first comprises, in unencrypted form, the identifier (Id) of the appropriate trusted third party for key recovery, as a function of the application type, followed by a dialogue key encrypted under the public key of this trusted third party, and lastly, encrypted under the public key (PK) of this trusted third party (TTP), the serial number of the approved hardware/software, a working key and the period of validity of this working key.
In addition, according to a variant, each key recovery field also comprises in the above-mentioned last field the identifier of the user entity or the manager of this hardware/software, also encrypted under the public key of the appropriate trusted third party for key recovery. As a result of this identifier, advantageously and as explained below, the trusted third party for key recovery can directly know the identity of the user entity or the manager without referring to either the hardware/software vendor or its representative or a user entity registration authority.
Finally, in a characteristic way, the working key in combination with, among other things, the date, is used to calculate the daily intermediate key, while this intermediate key is used to encrypt the dialogue key.
Thus, the choice of the trusted third party for key recovery is left to the application, and is therefore a dynamic choice which is a function of the application type or of the context, that is, specific to a field. In this way, the approved hardware/software can xe2x80x9cknowxe2x80x9d the choice and consequently the name of the appropriate trusted third parties for key recovery, a name which can be determined from the context of the application or user data, from the source and destination countries or even from elements of the hierarchical structure of the names. This same principle of dynamic choice ensures that the trusted third party cannot know this choice in advance. The identifier of the trusted third party for key recovery allows the national authority authorizing the trusted third parties to be given the decryption keys to identify the trusted third party for key recovery chosen. In order to verify that the compulsory control field created by the sender has been constituted so as to effectively render the decryption key of the message accessible to the various trusted third parties, the recipient""s hardware/software recalculates part of this compulsory control field, that is, it re-encrypts the dialogue key, which it also obtains by means of the key exchange protocol specific to the application, under the public key of each trusted third party and verifies that it obtains an identical result. If this is not the case, it refrains from decrypting the message.
This process, however, does not prevent a recipient""s accordingly modified hardware/software from bypassing this control and not refraining from decryption. Thus, as explained below, one of the novelties of the invention resides in the fact that the modification, during their transfer, of the correctly generated compulsory control and compensation fields, no matter what receiving hardware/software is used (compliant or modified), prevents the recipient from decrypting the message.
Normally, the standard key recovery systems are limited to directly encrypting the decryption key of the message under the key of each trusted third party. Consequently, it is necessary to consult a trusted third party in order to decrypt each individual decryption key. Thus, as will be explained below, another novelty of the invention resides in the fact that it makes it possible to supply the decryption authorities in advance with daily intermediate keys, which prevents the decryption authorities from having to use the services of a trusted third party in order to decrypt each message. In order to allow the authorities to receive in advance, the data that make it possible to reconstruct the decryption keys, the process, unlike the known techniques, combines the direct method for recovering the dialogue key by means of the public encryption key of the trusted third party with a second method for recovering the dialogue key using a four-level key hierarchy wherein firstly, the working key, the serial number of the approved hardware/software, the period of validity of this working key, and possibly, depending on the variant presented above, the identifier of the user or the manager of this hardware/software are encrypted under the public key of each trusted third party for key recovery, after which the working key, specifically in combination with the date, is used to calculate the daily intermediate key, then the daily intermediate key is used to encrypt a dialogue key. Since the working key is encrypted under the public key of the trusted third party for key recovery, it can be decrypted by this trusted third party and by this entirety alone, since furthermore, this working key cannot be used directly, but only indirectly, to decrypt the message. Consequently, in a characteristic way, the approved decryption hardware/software will calculate the daily intermediate key by means of a one-way function (also called a xe2x80x9cone-way hash functionxe2x80x9d by one skilled in the art) from the working key, and from the compulsory control field, that is, the current date, the agreement number and two key recovery fields. The two communicating entities normally exchange a decryption key according to a protocol of their own. Depending on the method used, the key exchanged is not considered to be this decryption key, but to be precisely the above-mentioned dialogue key. This dialogue key is therefore also directly accessible to the designated trusted third parties, because it is encrypted directly under their public key, but also because this dialogue key is also encrypted under a daily intermediate key. The two communicating entities calculate the decryption key from a one-way function using as parameters the dialogue key and the result of a collision-proof one-way function calculated on all of the components of the compulsory control field, the result then being combined with the compensation field by means of an exclusive OR.
Each of the trusted third parties performs the calculation of the decryption key in the same way, and is therefore capable of calculating the decryption key. The compensation field makes it possible to use a decryption key of any value, which can be the xe2x80x9cprivate keyxe2x80x9d type for an asymmetric algorithm or the xe2x80x9csecret keyxe2x80x9d type for a symmetric algorithm. In effect, the sender of the message adjusts the value of the key by means of the compensation field, since the result of the one-way function using as parameters the dialogue key and the result of a collision-proof one-way function calculated on all of the components of the compulsory control field cannot be predictable. Thus, due to the fact that the decryption key is a function of the compulsory control field and the compensation field, used jointly by the communicating entities and the trusted third parties, and that as indicated above, any alteration of the compulsory control field constituted normally at the source by the sender, makes it impossible to decrypt the message, the objectxe2x80x94and this is fundamentalxe2x80x94being to render the decryption key false for the recipient of the message as a result of any modification. In effect, a modification, however minimal, of any of the fields of the compulsory control field has the result of modifying the decryption key, thus preventing the decryption and therefore the comprehension of the semantics of the message. It is important to note that the present process makes it possible to choose, for each message, a different and completely random decryption key.

Key recovery process used for strong encryption of messages


The present invention relates to a distributed communication system including server for executing communications applications and service features for communications installations. Preferably, the system is provided as a private communication system, wherein the communications installations are connected to one another via a network preferably an IP-oriented. The communications installations each have a local software interface which can be used by the server to control the functionality of the communications installation. A central software interface in the server maps the respective local software interfaces of the individual communications installations in a single superordinate logical software interface. The central software interface is used by the communications applications to access the resources of the individual communications installations.

The present invention relates to a distributed communication system. Modem communication systems frequently are made up of a plurality of physically distributed, interlinked communications installations. In this context, each of the communications installations has its own switching intelligence and its own local database for storing data specific to the communications installation. Each local database specific to a communications installation is used for storing data required for independent operation of its respective communication installation. This is frequently referred to in the literature as 'standalone operation' of a communications installation. For example, the local data bases may store subscriber numbers, authorizations, exchange lines, direct-dial numbers, call numbers, configuration data, shortcode dialing destinations, etc., for the communications installation. To produce an interconnected network of such communications installations, each individual communications installation must be configured appropriately on an individual basis. In other words, each communication installation must be brought into line with the data stored in the other communications installations that form the network.
Generally, the communications installations additionally have software interfaces, frequently also referred to in the literature as programming interfaces. The software interfaces can be used to externally implement particular control functions of the respective communications installation, e.g. from a data processing device connected to the communications installation via a hardware interface. One example of such a software interface is the CSTA interface (Computer Supported Telecommunications Applications) standardized by the ECMA (European Computer Manufacturer Association). The CSTA interface can be accessed using an external hardware interface, such as a V.24 or S0 interface.
In a modem communication system that includes a plurality of interlinked communication devices, the external data processing device can also be connected directly to the network that connects the communication devices. Communications applications running on the external data processing device can thus use the network to access the software interfaces of the respective communication devices in the communication system.
However, within the context of known communications applications for implementing control functions for a communication device, only a single communication device can be selectively addressed. Therefore, in a communication system that includes a multiplicity of distributed and interlinked communication devices, each communication device requires device specific applications. All-embracing centralized implementation of applications has not been possible to date using the existing communications applications.

Mapping control functions of a plurality of communication installations into a single logical interface


An improved fuse including a fuse body formed of an electrically insulative material. The fuse body defines a cavity which extends from a first end of the fuse body to a second end of the fuse body. A fusible element is disposed within the cavity and extends from a first end face of the first end of the fuse body to a second end face of the second end of the fuse body. Insulated plugs are disposed within the cavity at the first and second ends of the fuse body wherein the plugs adhere to an interior surface of the fuse body and form seals that close the internal cavity. The fuse may further include end terminations that are applied to the ends of the fuse body in electrical contact with the fusible element.

Fuses are used as circuit protection devices and form an electrical connection with a component in a circuit to be protected. One type of fuse includes a fusible element disposed within a hollow fuse body. Upon the occurrence of a specified fault condition, such as an overcurrent condition, the fusible element melts or otherwise opens to interrupt the circuit path and isolate the protected electrical components or circuit from potential damage. Such fuses may be characterized by the amount of time required to respond to an overcurrent condition. In particular, fuses that comprise different fusible elements respond with different operating times since different fusible elements can accommodate varying amounts of current through the fusible element. Thus, by varying the size and type of fusible element, different operating times may be achieved.
When an overcurrent condition occurs, an arc may be formed between the melted portions of the fusible element. If not extinguished, this arc may further damage the circuit to be protected by allowing unwanted current to flow to circuit components. Thus, it is desirable to manufacture fuses which extinguish this arc as quickly as possible. In addition, as fuses decrease in size to accommodate ever smaller electrical circuits, there is a need to reduce manufacturing costs of these fuses. This may include reducing the number of components and/or using less expensive components, as well as reducing the number and/or complexity of associated manufacturing steps.
Consequently, there is a need to reduce the number of components and/or manufacturing steps to produce a fuse with improved arc extinguishing characteristics. It is with respect to these and other considerations that the present improvements have been needed.

This patent is subject to a terminal disclaimer.


A system and method for improving power consumption by providing the ability to detect whether a cover is placed on top of Infrared, IR, touch device. While the cover is in the open state, a certain amount of the light transmitted by the IR transmitters is directed upward and away from the IR receivers in the device. When the cover is closed, this light is reflected off of the cover and is incident on the IR receivers. The system of the present invention recognizes this increased level of received IR light and determines that the cover is in a closed position. Having made such a determination that the cover is placed on the device, the device's power savings system can switch to an appropriate power saving mode.

Compact and lightweight notebook, laptop computers have become increasingly popular due to their portability. In general, such a portable computer is composed of a main body having a keyboard and a lid, where the lid is hingedly attached to the main body of the portable computer. A flat panel display is typically mounted on the lid. Or in some instances it could be said that the flat panel display forms a lid covering the keyboard of the main body. Usually, the lid is closed when the portable computer is not in use. Many of these devices include mechanisms, typically mechanical, to detect the closure of the lid. These detection mechanisms are tied to power saving circuitry, hardware or software, to effectuate a power savings mode when the lid is detected as closed. Similar detection and power savings mode have been employed in flip phones.
However, the aforementioned mechanical lid detection mechanism do not work for tablet type devices that do not have an integrated cover.

Infrared reflection based cover detection


In an optical communication system in which communication is conducted by transmitting light through a plastic optical fiber with a core diameter in the range from 300 to 600 μm, the average beam diameter and beam divergence angle expressed in terms of numerical aperture (NA) of the light at the input face of the optical fiber are set less than or equal to 250 μm, more preferably less than or equal to 200 μm, and less than or equal to 0.25, more preferably less than or equal to 0.2 respectively.

1. Field of the Invention
The present invention relates to an optical communication system that uses a plastic optical fiber as the transmission line.
2. Description of the Related Art
In optical communication systems, single mode or multimode optical fibers made mainly of silica glass have been used as the optical transmission lines. In general, the core diameter of these optical fibers is less than 100 μm, and very precise core alignment with an allowance of few micrometers is required when splicing the fibers. Consequently, installation work for optical fibers under common environments, including construction sites or the like, is no easy task. This has been an obstacle that lies in the way toward wider use of optical communication systems using optical fibers.
In the mean time, plastic optical fibers having larger core diameters for use with optical communication systems have also been developed as described, for example, in U.S. Patent Application Publication No. 20050232537. Most of these fibers, however, have step index structures due to manufacturing constraints, making them difficult to transmit signals at high speeds over a long distance. Recently, however, a graded index type plastic optical fiber (GI-POF) that has a large core diameter, yet without these drawbacks described above and is applicable to high speed transmission has proposed, and is currently under development for practical applications.
Further, there is a growing demand in the market for an optical communication system capable of transmitting both high and low speed signals. Consequently, a communication system having two transmitters is proposed. One of the transmitters is equipped with a semiconductor laser for high speed signal transmission, and the other is equipped with an inexpensive RC-LED (Resonant Cavity Light Emitting Diode) for low speed signal transmission. The system uses a GI-POF applicable to both high and low speed signal transmission as the transmission line, and either of the transmitters is selected according to the speed of the signal to be transmitted.
As for the plastic fibers applicable to both high and low speed signal transmission, medium diameter GI-POFs with a core diameter in the range from 300 to 600 μm and a numerical aperture in the range around from 0.2 to 0.4 have been developed. Hereinafter, the medium diameter GI-POF will be described in detail.
Basically, such a GI-POF includes a core with a diameter in the range from 300 to 600 μm, and a clad with a thickness of several tens of micrometers surrounding the core. The refractive index of the core is slightly higher than that of the clad in order to confine the propagating light within the core as in an ordinary optical waveguide. A low molecular weight compound having a high refractive index with a large molecular volume is added to the core as a refractive index adjuster. The compound is distributed in the radial direction with the center of the core having a highest refractive index. The refractive index profile "g" within the core is adjusted to a value in the range from 1 to 5. The numerical aperture (NA) of the optical fiber may be defined by the following formula using the maximum refractive index N1 of the core and the refractive index N2 of the clad. In the medium diameter GI-POF, the difference ΔN {=(N1+N2)/N1} is adjusted so that the value of the NA falls in the range from 0.2 to 0.4.NA=N1√{square root over (2ΔN)}
In the mean time, any material may be used for the clad as long as it has favorable characteristics for optical transmission, such as providing a lower refractive index than that of the core and the like. In particular, however, use of fluorinated polymers is preferable from the view point of refractive index. More specifically, polyvinylidene fluoride (PVDF, N2=1.42 for wavelength at 650 nm) may be listed as one of such materials. Likewise, as for the material of the core, any material may be used as long as it has favorable characteristics for optical transmission. In particular, however, polymers having high optical transparency are preferable. Here, use of amorphous polymers is preferable in order to prevent optical anisotropy from developing or to reduce it. Further, use of polymers having superior adhesiveness with each other is preferable for the core and clad. Still further, use of polymers having superior mechanical and thermal resistance properties is more preferable.
Specific material examples of the core may include (meta) acrylic esters (fluorine-free (meta) acrylic ester, fluorine containing (meta) acrylic ester), styrene compounds, vinylesters, polymerized compounds produced using bisphenol A, which is a raw material of polycarbonates and the like as polymerizable compounds. Further, homopolymers produced by using these materials as raw materials and polymerizing each of the materials, copolymers produced by combining two or more of the materials in various ways and polymerizing them, or mixtures produced by combining the honopolymers and copolymers in various ways may be used as the material of the core. Of these, (meta) acrylic esters or fluorine polymer based materials are particularly preferable to form an optical transmission body. In the mean time, if an optical element is used for near-infrared applications (e.g., light source, transmission, or the like at a wavelength in the range from 750 to 850 nm), an absorption loss occurs due to C—H binding forming the optical element. The wavelength region where the absorption loss occurs may be shifted to a longer wavelength region by the use of a polymer in which hydrogen atoms in C—H binding are substituted by deuterium atoms, fluorine atoms, or the like as described, for example, in U.S. Pat. No. 5,541,247 and Japanese Unexamined Patent Publication No. 2003-192708. In this way, the transmission loss of the light transmitted through the optical fiber may be reduced. Such polymers include deuterated polymethyl methacrylate (PMMA-d8), polytrifluoroethyl methacrylate (P3FMA), polyhexafluoro isopropyl 2-fluoroacrylate (HFIP 2-FA), and the like. Preferably, impurities and foreign substances that may act as light scattering sources are removed sufficiently from the raw material compound prior to polymerization in order to ensure the transparency of the material after polymerization.
In the mean time, it has been revealed that when an optical signal is transmitted through the medium diameter plastic optical fiber with a core diameter in the range from 300 to 600 μm as described above by the optical communication system using the transmitter equipped with a RC-LED for low speed transmission, the transmitted optical signal may be attenuated by the optical fiber greater than expected. More specifically, as shown in FIG. 7, light L emitted from a light source constituted by a RC-LED 2 having a luminous section 2 with a diameter of 100 μm enclosed by a transparent resin 4 having a lens-like convex section 3 was inputted to an optical fiber (GI-POF) with a core diameter of 500 μm and transmitted through the fiber, an unexpectedly large amount of transmission loss exceeding 250 dB/km was measured.
In view of the circumstances described above, it is an object of the present invention to provide an optical communication system that uses a medium diameter plastic optical fiber, such as the GI-POF or the like, yet capable of achieving low transmission loss.


A method and system providing category based sort and display instructions for a computer system having a database of information stored therein are described. A database of contact information is maintained in the computer with each record containing information related to a personal contact. Each record can be assigned a custom category type defining the kind of contact that the record is. The user is allowed to display a condensed listing of the contacts associated with each category. When the list is displayed, the list can be sorted by a field specific to that category type. Each category type can have its own sorting instructions. The sorting instructions also define the way in which the lists are displayed. The user can define and edit the category based instructions at any time.

1. Field of the Invention
The present invention relates to the field of data processing. More specifically, embodiments of the present invention relate to the display of information records stored within a database of an electronic device, e.g., a computer system, a portable computer system, a palmtop computer system, or any other hand-held electronic device that utilizes a display screen, such as a cell phone, a pager, etc.
2. Related Art
As the components required to build a computer system have reduced in size, new categories of electronic devices and computer systems have emerged. One of the new categories of computer systems is the "palmtop" computer system. A palmtop computer system is a computer that is small enough to be held in the hand of a user and can therefore be "palm-sized." Most palmtop computer systems are used to implement various Personal Information Management (PIM) applications such as an address book, a daily organizer (calendar, datebook, etc.) and electronic notepads, to name a few. Palmtop computers with PIM software have been know as Personal Digital Assistants (PDAs). Many PDAs have a small and flat display screen associated therewith.
In addition to PDAs, other portable electronic devices have display screens, such as cell phones, electronic pagers, remote control devices and other wireless portable devices. All of these devices have been adapted to display short lists of information on the display screens to help the user organize and display information, e.g., phone records.
User convenience is a very important factor for portable electronic devices. Typically, portable electronic devices are employed while the user is on the run, e.g., in business meetings, on business travel, personal travel, in a vehicle, on foot, etc. Because the user may be occupied or busy while using the portable electronic device, the number of user steps or user tasks required in order to access information from an electronic device (or to store information into the electronic device) is crucial for producing a commercially successful and useful product. That is, the more difficult it is to access data from an electronic device, the less likely the user will perform those tasks to obtain the information. Likewise, the easier information is to obtain, the more likely the portable electronic device will be used to obtain that information and the more likely the portable electronic device will become a part of the user's everyday activities.
A popular database program for displaying and organizing contact information is the "address book" database application found in PDAs and in some intelligent cell phones. This application allows a user to enter records concerning their personal contacts, e.g., person's name, address, company, telephone numbers, email addresses, etc. Each record can be assigned a particular category, e.g., friend, business, family, etc. When looking for records, the categories can be used as filters, e.g., a list of the records of a designated category can be displayed where each record is condensed into just one line in the display. The condensed list can be quite long and therefore provision is made allowing the user the ability to scroll up and down through the list.
The application program sorts the lists by a designated record field. For instance, the lists can be sorted, and thereby displayed in sort order, according to last name. However, in the "address book" database application, all categories of records are sorted based on the same designated record field regardless of the category designation. In other words, if the sort and display field is based on last name, then all records, e.g., family, friends, business contacts, etc., are sorted and displayed based on this field. Unfortunately, while last name may be an adequate sort field for friends, it may not be appropriate (and it may not be optimized) for locating business contacts. Importantly, a single sort preference for the entire application, irrespective of the individual category, does not allow users to customize their sort order based on how they, as individuals, remember people's contact information.

Category specific sort and display instructions for an electronic device


The present invention is directed to a novel phosphorescent compound formed by synthesizing an orthometallated complex by using easily-synthesized ligands. The invention is further directed to an electroluminescent device having high luminous efficiency by using the phosphorescent compound. Moreover, the invention is also directed to a light-emitting device operating at a low voltage by using the electroluminescent device. According to the present invention, a phosphorescent compound represented by general formula [formula 1] is synthesized. Further, an electroluminescent device containing the phosphorescent compound is formed. In order to generate phosphorescent emission more efficiently, a heavy metal is preferably used as a central metal from the perspective of heavy atom effects. Therefore, one feature of the present invention is that the central metal M in the below general formula [formula 1] is iridium or platinum

1. Field of the Present Invention
The present invention relates to the compound in which light emission is generated through the triplet excited state (hereinafter, phosphorescent compound). Further, the invention relates to an electroluminescent device having an anode, a cathode, and a layer containing an organic compound in which light is generated when an electric field is passed through the layer (hereinafter, electroluminescent layer) and phosphorescent compounds are contained, and a light-emitting device having the electroluminescent device.
2. Description of the Related Art
Organic compounds (an organic molecule) undergo transitions to the energy state having the highest energy (excited state) when they absorb light. Through the excited state, various reactions (photochemical reactions) or luminescence may occur. Hence, there are many applications of the organic compounds.
A reaction of singlet oxygen with unsaturated organic molecules (oxygen addition) is an example of a photochemical reaction. For example, refer to Haruo INOUE, Katsuhiko TAKAGI, Masako SASAKI, and Syosinn BOKU, "Basic Chemistry Course PHOTOCHEMISTRY I", Maruzen Corporation, pp. 106-110 (1999). Since the ground state of oxygen molecules is a triplet state, singlet state oxygen (singlet oxygen) is not produced by direct photoexcitation. However, in the presence of another triplet excited molecules, singlet oxygen can be produced, and it causes an oxygen addition reaction. Here, compounds capable of producing the foregoing triplet excited molecules are referred to as a photosensitizer.
As stated above, in order to produce singlet oxygen, a photosensitizer capable of producing triplet excited molecules by photoexcitation is required. However, since the ground state of general organic compounds is a singlet state, the photoexcitation to a triplet excited state is a forbidden transition, that is, the probability of generating triplet excited molecules is very small (generally, singlet excited molecules are generated). Therefore, as the photosensitizer, the compounds that are subjected to intersystem crossing between a singlet excited state and a triplet excited state are required. In other words, such compounds are beneficial in use as a photosensitizer.
Further, the compounds that are subjected to intersystem crossing may emit phosphorescence. Phosphorescence is the light emission that occurs from a transition between electronic states of different multiplicities, that is, the light emission occurs from a transition from the triplet excited state back down to the singlet ground state in typical organic compounds. (Further, fluorescence is the light emission that occurs from a transition from the singlet excited state back to the singlet ground state.) Compounds capable of emitting phosphorescence (phosphorescent compound) can be applied to an electroluminescent device containing organic compounds as light-emitting compounds (a device in which light is emitted when an electric field is passed through the device), for example.
When an organic compound is used as a light emitter, the emission mechanism of an electroluminescent device is a carrier injection type. That is, a voltage is applied to an electroluminescent layer interposed between a pair of electrodes, and electrons injected from a cathode and holes injected from an anode are recombined with each other within the electroluminescent layer to produce excited molecules (hereinafter, molecular exciton), then, the molecular exciton radiates energy while returning to the ground state to emit light.
In such an electroluminescent device, an electroluminescent layer is formed generally to have a thin film thickness less than 1 μm. An electroluminescent device does not require backlight, which is used for the conventional liquid crystal display device, since an electroluminescent layer emits light itself, that is, the electroluminescent device is a self-luminous device. Therefore, it is highly advantageous that an electroluminescent device can be fabricated to have extremely thin film thickness and be lightweight.
In an electroluminescent layer with a thickness of about 100-200 nm, it takes several (approximately ten) nanoseconds for the process from injection to recombination of carriers in the light of the carrier mobility. Hence, the time required for the process from injection of carriers to light emission of the electroluminescent layer is on the order of a microsecond even including the process of recombination of carriers. Thus, an extremely high response speed is also one of the advantages.
Further, since an electroluminescent device is a light-emitting device of a carrier injection type, it can be operated at a direct current voltage, thereby noise is hardly generated. With respect to a driving voltage, an electroluminescent layer is formed into an even ultra thin film with a thickness of approximately 100 nm, and an electrode material is selected so as to reduce a carrier injection barrier to the electroluminescent layer. Further, a hetero structure (two-layers structure) is employed. Accordingly, a sufficient luminance of 100 cd/m2 can be obtained at an applied voltage of 5.5 V. For example, refer C. W. Tang and S. A. VanSlyke, "Organic electroluminescent diodes", Applied Physics Letters, vol. 51, No. 12, 913-915 (1987).
An electroluminescent device has attracted attention as a flat panel display device of a next generation in terms of its characteristics such as thin shape and lightweight, high response speed, direct current low voltage operation, or the like. In addition, an electroluminescent device is a self luminous device, has a wide viewing angle, and has high level of visibility so that it is considered that the electroluminescent device can be used effectively as a device for the display screen of a portable device.
Further, emission observed in an electroluminescent device is the emission phenomenon which occurs from the transition of a molecular exciton back down to the ground state. Here, a singlet excited state (S*) and a triplet excited state (T*) are examples of types of the molecular exciton formed by an organic compound, which is the same as in the case of photoexcitation. In addition, their statistic generation ratios in an electroluminescent device are considered to be S*:T*=1:3. For example, refer to Tetsuo TSUTSUI, "Textbook of the 3rd seminar at Division of Organic Molecular Electronics and Bioelectronics, The Japan Society of Applied Physics", p. 31 (1993).
However, light emission (phosphorescence) from a triplet excited state is not observed in typical organic compounds at room temperature. Generally, only light emission from a singlet excited state (fluorescence) is observed. Since the ground state of an organic compound is generally a singlet ground state (S0), the transition of T* to S0 (phosphorescence process) is an intense forbidden transition, and the transition of S* to S0 (fluorescence process) is an allowed transition. That is, light emission generally occurs from only a singlet excited state.
Therefore, the theoretical limit of internal quantum efficiency (the number of photons released per carriers injected) of an electroluminescent device is considered to be 25% based on the fact that S*:T*=1:3.
Also, light generated is not entirely emitted to the outside, and a part of the light cannot be extracted because of component materials of an electroluminescent device (electroluminescent layer materials, electrode materials) or the substrate materials-specific refractive index. The efficiency of extraction of generated light is referred to as light extraction efficiency. The light extraction efficiency of an electroluminescent device having a glass substrate is said to be approximately 20%.
For these reasons, even if all injected carriers form molecular exciton, the theoretical limit of the ratio of photons extracted finally emitted to the outside to the number of injected carriers (hereinafter, external quantum efficiency) has been said to be 25%×20%=5%. That is, even if all carriers are recombined, only 5% thereof can be extracted as light emission.
However, in recent years, an electroluminescent device in which energy released from a transition of a triplet excited state (T*) back down to the ground state (hereinafter, triplet excited energy) can be converted into light emission has been reported successively. The high luminous efficiency has attracted attention. For example, refer to D. F. O'Brien, M. A. Baldo, M. E. Thompson and S. R. Forrest, "Improved energy transfer in electroluminescent devices", Applied Physics Letters, vol. 74, No. 3, 442-444 (1999), referred to herein as "O'Brien et al." For another example, refer to Tetsuo TSUTSUI, Moon-Jae YANG, Masayuki YAHIRO, Kenji NAKAMURA, Teruichi WATANABE, Taishi TSUJI, Yoshinori FUKUDA, Takeo WAKIMOTO and Satoshi MIYAGUCHI, "High Quantum Efficiency in Organic Light-Emitting Devices with Iridium-Complex as a Triplet Emissive Center", Japanese Journal of Applied Physics, Vol. 38, pp. L1502-L1504 (1999), referred to herein as "Tsutsui et al. (vol. 38)."
In O'Brien et al., a porphyrin complex containing platinum as a central metal is used. In Tsutsui et al. (vol. 38), an organometallic complex containing iridium as a central metal is used. Both of the complexes are phosphorescent compounds containing 3rd transition series elements as central metals. Some of them have a phosphorescent compound having external quantum efficiency beyond the above mentioned theoretical limit value, 5%.
Further, a layer comprising an organometallic complex (iridium complex) containing iridium as a central metal and a layer comprising DCM2, a known fluorescent compound, are stacked alternately to transfer triplet excited energy generated in the iridium complex into the DCM2. Consequently, light emission of the DCM2 also can be excited, as in M. A. Baldo, M. E. Thompson and S. R. Forrest, "High-efficiency fluorescent organic light-emitting devices using a phosphorescent sensitizer", Nature (London), vol. 403, 750-753 (2000), referred to herein as "Baldo et al." Light emission of DCM2 is the light emission (fluorescence) occurring from a singlet excited state. The electroluminescent device having the foregoing device configuration has the advantage that triplet excited energy of an iridium complex generated efficiently can be utilized for singlet excited energy of the DCM2 which is another molecule. As one might say, the iridium complex used as a phosphorescent compound serves as the above-mentioned photosensitizer to increase the ratio of singlet excited state of the DCM2.
As disclosed in O'Brien et al., Tsutsui et al. (vol. 38) and Baldo et al., the organic compounds in which light emission is generated through the triplet excited state, that is, an electroluminescent device containing phosphorescent compounds can achieve higher external quantum efficiency than that of the conventional device. High external quantum efficiency leads to improved luminance. Therefore, an electroluminescent device containing phosphorescent compounds will play a great role in the development of an electroluminescent device in the future as means for improving luminance and luminous efficiency.
Accordingly, phosphorescent compounds are expected to be used as a photosensitizer or a material for an electroluminescent device because the phosphorescent compounds are subject to intersystem crossing and emit light (phosphorescence) from the triplet excited state. However, the number of applicable phosphorescent compounds is few under the existing circumstance.
An iridium complex, in a few phosphorescent compounds, disclosed in Tsutsui et al. (vol. 38) or Baldo et al., is one type of organometallic complexes referred to as an orthometallated complex. The iridium complex has a phosphorescence lifetime of several hundred nanoseconds and high phosphorescence quantum efficiency so that the decrease in efficiency as luminance is improved is less than that of the porphyrin complex. With such a perspective, the orthometallated complex containing such a heavy metal serves as a guide to synthesize phosphorescent compounds.
The structure of the ligand of the iridium complex disclosed in Tsutsui et al. (vol. 38), which is comparatively simple and gives green emission with good color purity, should be altered in order to vary the emission color to another. For example, it is disclosed that some emission colors were achieved by synthesizing various ligands and iridium complexes containing the foregoing various ligands in M. Thompson, S. Lamansky, P. Djurovich, D. Murphy, F. Abdel-Razzaq, S. R. Forrest, M. Baldo, P. E. Burrows, C. Adachi, T. X. Zhou and J. J. Brown, "Phosphorescent Materials and Devices", The 10th International Workshop on Inorganic and Organic Electroluminescence (EL '00), 35-38.
In addition, many of the foregoing ligands have difficulty in synthesis or the number of processes for the synthesis is large, and it causes an increase of cost. In order to emit phosphorescence in an orthometallated complex, it is necessary to use iridium or platinum as a central metal; however, these metal materials are expensive, and it causes an increase of cost of the ligands eventually. Further, blue emission with good color purity has not been realized yet.
Therefore, it is required to explore various emission colors by synthesizing a novel orthometallated complex (phosphorescent compound) by using ligands that can be synthesized easily.

Phosphorescence compound and electro field light emitting device having the same

Semiconductor Energy Laboratory Co., Ltd.


A recognition algorithm in automotive vehicles having electronic throttle control interprets a combination of operator commands including braking and acceleration commands and imposes a restriction on vehicle motion until a predetermined combination of operator commands are detected.

The application of electronic control to internal combustion engine intake air metering is generally known in the art of engine control. Typically, such control includes a controlled actuator connected to a throttle valve, such as a conventional butterfly valve, wherein valve position is adjusted by controlled actuator motion to provide appropriate restriction on air passage into the engine. The actuator is in communication with a controller which controls actuator motion when air is to be metered to the engine. The controller may be responsive to any one of several ingredients used to formulate the current desired throttle position. For example, such ingredients may include inputs indicative of the engine operating condition, an operator command from an accelerator pedal, or information from an active cruise control algorithm, an active idle speed control algorithm, or an active traction control algorithm. Further, feedback may be provided to the controller, such as from a conventional throttle valve position sensor communicating a signal to the controller the magnitude of which is related to the degree of opening of the throttle valve. Corrective positioning of the actuator or diagnostics may be carried out by the controller in response to the sensor feedback signal.
The advantages of electronic control of intake air metering are well known. For example, an important advantage is that the electronic control may replace the traditional, substantially inflexible cable assembly connecting the vehicle accelerator pedal or its equivalent and the throttle valve. The electronics provide opportunities in vehicle control and diagnostics that were unavailable traditionally. A control opportunity resides in determining and acting on operator intent, which may not be most accurately reflected in traditional driver inputs.

Recognition algorithm for electronic throttle control


Vectors, nucleic acid sequences and amino acid sequences that confer improved characteristic to plants, plant cells, plant material, seed of plants and regenerated plants comprising vectors, nucleic acid and amino acid sequences as compared to wild-type plants cultivated under identical conditions.

There are more than 300,000 species of plants. They show a wide diversity of forms, ranging from delicate liverworts, adapted for life in a damp habitat, to cacti, capable of surviving in the desert. The plant kingdom includes herbaceous plants, such as corn, whose life cycle is measured in months, to the giant redwood tree, which can live for thousands of years. This diversity reflects the adaptations of plants to survive in a wide range of habitats. This is seen most clearly in the flowering plants (phylum Angiospermophyta), which are the most numerous, with over 250,000 species. They are also the most widespread, being found from the tropics to the arctic.
The process of plant breeding involving man's intervention in natural breeding and selection is some 20,000 years old. It has produced remarkable advances in adapting existing species to serve new purposes. The world's economics was largely based on the successes of agriculture for most of these 20,000 years.
Plant breeding involves choosing parents, making crosses to allow recombination of gene (alleles) and searching for and selecting improved forms. Success depends on the genes/alleles available, the combinations required and the ability to create and find the correct combinations necessary to give the desired properties to the plant. Molecular genetics technologies are now capable of providing new genes, new alleles and the means of creating and selecting plants with the new, desired characteristics.
Plants specifically improved for agriculture, horticulture and other industries can be obtained using molecular technologies. As an example, great agronomic value can result from modulating the size of a plant as a whole or of any of its organs. The green revolution came about as a result of creating dwarf wheat plants, which produced a higher seed yield than taller plants because they could withstand higher levels and inputs of fertilizer and water.
Similarly, modulation of the size and stature of an entire plant, or a particular portion of a plant, allows production of plants better suited for a particular industry. For example, reductions in the height of specific ornamentals, crops and tree species can be beneficial by allowing easier harvesting. Alternatively, increasing height may be beneficial by providing more biomass. Other examples of commercially desirable traits include increasing the length of the floral stems of cut flowers, increasing or altering leaf size and shape, enhancing the size of seeds and/or fruits, enhancing yields by specifically stimulating hormone (e.g. Brassinolide) synthesis and stimulating early flowering or evoking late flowering by altering levels of gibberellic acid or other hormones in specific cells. Changes in organ size and biomass also result in changes in the mass of constituent molecules such as secondary products.
To summarize, molecular genetic technologies provide the ability to modulate and manipulate growth, development and biochemistry of the entire plant as well as at the cell, tissue and organ levels. Thus, plant morphology, development and biochemistry are altered to maximize or minimize the desired plant trait.

Nucleotide sequences and polypeptides encoded thereby useful for modifying plant characteristics and phenotypes


The invention is a very lightweight pad or base for use with a small portable stove such as those used by backpackers or mountaineers. It provides a stable bearing surface when the stove is used on unstable surfaces such as snow or sand. The pad comprises an exterior frame which completely encloses a spider-like structure on which the stove rests. Preferably two legs of the spider have upstanding cleats to engage the base of the stove. A third leg has an attached spring which also engages the stove base to bias it firmly against the cleats and hold the stove in place. These legs are preferably spaced about 120.degree. apart. The spider may contain additional legs to increase strength and bearing surface. Since the cleats are of very low profile the pad is essentially planar and takes up little space in a backpack.

The present invention is a stove pad that provides a stable base for a portable stove such as those used by mountaineers, campers, and backpackers.
The popularity of mountaineering and backpacking has grown almost exponentially over the past three decades. Hiker traffic in the back country has become so heavy that in some national parks and wilderness areas access is limited to a given number of hikers in order to prevent wear on fragile meadows and camping areas. In many locations the readily available firewood has long ago been used up and management authorities now require overnight hikers to carry stoves and fuel for cooking. Such stoves have always been needed by mountaineers and other who might be camping above timberline or on snow. These stoves must be small enough to readily fit in a backpack and light enough so that they will not overly burden the hiker. Generally they weigh less than 1 kg. The stoves normally are designed to use either kerosine or white gasoline for fuel. Examples can be seen in U.S. Pat. Nos. 3,877,458 and 4,177,790.
Hikers must occasionally camp in small areas that are less than desirable from the standpoint of comfort and convenience. In many mountain areas flat surfaces for camp locations are at a high premium or unavailable. The typical camp stove has a relatively small basal area and needs a firm flat surface to hold the cooking utensils level. Snow camping poses particular problems. Even if the snow is packed hard, heat conducted and reflected from the stove will cause it to melt into the snow, usually with disastrous results for the camper's dinner. To counter this problem, campers often carry small squares of plywood or foam insulation as a stove base. Unfortunately, these improvised bases tend to be heavy and/or hard to accommodate in the limited space within a backpack. Stoves having a higher effective basal area, such as the one shown in U.S. Pat. No. 3,189,016, while sufficiently stable on solid ground, still require some sort of insulating base when used on snow.
Apparently nobody before the present inventor has seriously addressed the problem of providing a stove pad or base that gives maximum bearing surface with minimum bulk and weight and that will readily fit into a pack.
U.S. Pat. No. Des. 264,928 shows a pot or pan restraint for engaging the radial bars of a stove top grating. U.S. Pat. No. Des. 282,340 illustrates a base for a cooking pot, such as a wok. This presumably would hold the wok over a stove burner or allow it to be placed on a table. U.S. Pat. No. Des. 316,007 describes a stand for a fondue pot or similar article. While remotely similar in purpose, none of these articles addresses the problems outlined above and none would meet both requirements of light weight and minimum bulk.


An Almen type gage with an improved test strip support mechanism, which concentrates the holding force at the contact points. The support mechanism includes four paired contact balls and a permanent magnet engaged between the paired balls to magnetically hold the test strip against the contact balls. Each contact ball seated atop a set screw turned into a test platform with the magnetic flux of the permanent magnets passing through both the contact balls and the set screws.

U.S. Pat. No. 2,350,440 to John O. Almen discloses a device used for measuring the intensity of shot blast peening on metal parts, commonly known as an Almen gage. Almen gages measure the intensity of the peening process by measuring the curvature of thin metal test strips, after one side of the test strips have been peened. The unbalanced stress in the peened surface causes the test strips to bow. The Almen gage uses two spaced knife edged supports and a measurement indicator with an reciprocating feeler to measure the curvature of the test strip. The spaced knife edged supports hold the test strip as the feeler located between the knife edges engages the test strip. Gaging the height of the arc or bend of the test strip between the two predetermined contact points along the knife edged supports provides an indication of the intensity of the peening process.
Later refinements of the Almen gage have replaced the knife edged supports with four round contact balls with the operator manually holding the test strip in place for measurement. Another version of the Almen gage added a spring loaded finger to hold the test strip in place. The spring loaded finger was difficult to operate and subject to abuse and damage. The latest revision in the Almen gage incorporated a large permanent magnet centrally mounted in the base to draw the strip against the contact balls. Generally, the magnet was spaced some distance from the test strip, which necessitated the use of a large powerful magnet. The magnetic flux of such large magnets tended to deflect the thin test strips and corrupt the measurement readings. The location of the magnet also forced the indicator stems to be constructed of non-magnetic materials in order to avoid magnetic influence, which would affect the indicator's free travel.

Gage for measuring the intensity of shot-blast peening


In a radar system, harmonic excitation of an antenna is carried out in different frequency ranges. The antenna characteristic which varies as a function thereof is used to analyze different solid angle ranges around an object.

A pulse-Doppler radar system for measuring distance or speed in a motor vehicle is described in U.S. Pat. No. 6,362,777. Therein, a multiplier or a mixer is provided in the transmit path for supplying a signal having double the frequency of a reference oscillator to the transmitting antenna. Frequency doubling is carried out there in order to be able to use a reference oscillator having a lower frequency and thus more stable behavior.

Radar system, in particular for measuring distance and/or speed


An optical module is provided with an optical waveguide array comprising plural optical transmission lines; a photoelectric element array comprising plural photoelectric elements for respectively receiving or transmitting optical signals from or to the optical transmission lines of the optical waveguide array; and a lens component interposed between the photoelectric element array and the optical waveguide array, and having first and second convex lenses respectively placed opposite the optical waveguide array and the photoelectric element array, and respectively having effective diameters larger than the distance between the respective optical axes of the mutually most-distant two optical transmission lines of the optical waveguide array, and the distance between the respective optical axes of the mutually most-distant two photoelectric elements of the photoelectric element array.

1. Field of the Invention
The present invention relates to an optical module for transmitting, receiving or transmitting/receiving plural optical signals.
2. Description of the Related Art
At distal ends of optical communication systems, an optical module is used for transmitting/receiving optical signals converted from electrical signals to/from optical transmission lines, respectively, such as optical fibers. Particularly, an optical module is used that has a PD array or an LD array packaged therein to transmit or receive plural optical signals.
FIG. 15 is a plan view for explaining a reception optical module that receives respective optical signals from plural optical fibers with plural light-receiving elements (e.g., photodiodes: PDs) respectively.
As shown in FIG. 15, an optical module 120 comprises an optical fiber array 122 having plural optical fibers 121, a PD array 124 having plural light-receiving elements (PDs) 123 for respectively receiving respective optical signals from the optical fibers 121 of the optical fiber array 122, and a lens component 125 interposed between the PD array 124 and the optical fiber array 122 for discretely guiding the optical signals between the optical fibers 121 of the optical fiber array 122 and the corresponding PDs 123 of the PD array 124. The lens component 125 is provided with plural optical fiber side convex lenses 126 and plural PD side convex lenses 127.
The respective optical signals emitted from the optical fibers 121 are collimated by the optical fiber side convex lenses 126 respectively, so that each collimated light (parallel light) is collected by the PD side convex lenses 127 respectively, and received by the corresponding PDs 123 substantially at focal position. In this optical module, because one set of the convex lenses (micro lenses) is provided for each optical fiber and PD corresponding thereto, the respective optical signals from the optical fibers 121 can be discretely coupled to the PDs 123 (See JP-A-2005-31556).
The lens component 125 packaged in the conventional optical module 120 uses the plural micro lenses arranged parallel to each other to discretely collimate the plural optical signals. However, for example, because of a specified spacing between the PDs 123 of the PD array 124, in the case of a small spacing (pitch) between the optical fibers 121 or the PDs 123, the diameter (effective diameter or aperture) of the convex lenses has to be small. Also, the NA (No. of apertures) of the optical fibers 121 is predetermined, and light (optical signals) are emitted therefrom with a predetermined expansion angle. Thus to inject light emitted from the optical fibers 121 into a small diameter lens without loss, i.e., to inject thereinto light when the beam diameter of the emitted light is smaller than the diameter of the lens), the LDs or PDs 123 have to be provided right close to the PD side convex lenses 127 of the lens component 125.
However, for the structural reason of LD or PD packages with LDs or PDs, there is the problem that they cannot be arranged within the focal distance of the lenses. That is, there is the problem that LDs or PDs cannot be arranged in a desired position in the optical module, regardless of structure of LD or PD packages.
Also, generally, convex lenses that are slightly contaminated with dust degrade optical signals transmitted therethrough. In the conventional optical module 120, because the diameter of the convex lenses is small and the size ratio of contamination to lens diameter (optical signal diameter) is therefore large, there is the problem that contamination adhering to lens surface degrades optical signals.
As shown in FIG. 16, in collecting plural (e.g., four) optical signals to plural optical fibers 132 arranged at a specified interval, when the plural optical signals are injected into one lens 131 having a diameter that allows them to be injected thereinto, the respective optical axes of the optical signals passed through the lens 131 are not parallel to each other, to be injected obliquely into the plural optical fibers 132 respectively arranged parallel to each other, which therefore causes coupling loss.


A method of signaling bearer connection on Iu interface for MBMS service, includes the following steps: (a) RNC receives a MBMS Notification message for a certain MBMS service from SGSN; (b) RNC constructs a MBMS Service Request message according to the contents of the notification; (c) RNC sends a SCCP Connection Request message to SGSN, requests to establish a SCCP signaling connection, and then waits for a reply; (d) RNC receives a SCCP Connection Confirmation message from SGSN. This invention solves the problem of signaling connection on Iu interface after MBMS service is introduced into the existing mobile communication system. The connection mode provided in this invention can reasonably utilize network resources, effectively reduce signaling congestion on Iu interface and reduce modifications to the existing Iu interface message.

1. Field of the Invention
This invention relates to Multimedia Broadcast/Multicast Service in Wideband Code Division Multiple Access (hereinafter referred to as WCDMA) mobile communication system, more specifically relates to a method for signaling bearer connection of Multimedia Broadcast/Multicast Service on Iu interface (the interface between Radio Access Network and Core Network).
2. Description of the Prior Art
Multimedia Broadcast and Multicast Service (hereinafter referred to as MBMS) is a new service under standardization by 3rd Generation Partnership Project (hereinafter referred to as 3GPP). MBMS service is an unidirectional point-to-multipoint (p-t-m) service, whose most remarkable characteristic is that it can make use of radio resources and network resources efficiently.
The architecture of the MBMS system is described in brief in combination with FIG. 1.
MBMS network structure adds new network elements based on the core network of General Packet Radio Service (hereinafter referred to as GPRS). Broadcast and Multicast Service center 101 (hereinafter referred to as BM-SC) is the service control center of MBMS system. Gateway GPRS Supporting Node 102 (hereinafter referred to as GGSN) and Service GPRS Supporting Node 103 (hereinafter referred to as SGSN) constitute the transmission network of MBMS service and provide route for data transfer. Home Location Register 106 (hereinafter referred to as HLR) saves the data related to user and can provide services such as user's authentication or the like. UMTS Terrestrial Radio Access Network 104 (hereinafter referred to as UTRAN) provides radio resources for MBMS service over the air-interface. Iu 107 indicates the interface between Radio Access Network and Core Network. User Equipment 105 (hereinafter referred to as UE) is the terminal device for receiving data. Radio resources used by MBMS service are not dedicated for one user, but are shared by all users using this service.
(1) Signaling Connection Mode of the Existing Iu Interface
In order to transfer message of layer 3 between UE and CN, the existing Radio Access Network Application Part (hereinafter referred to RANAP) establishes a signaling connection for each activated UE. RANAP supports two modes, i.e. connection-oriented and connectionless-oriented.
(2) Signaling Connection Establishment and Release of the Existing Iu Interface
When information of UE and CN needs to be exchanged between Radio Network Controller (hereinafter referred to as RNC) and CN and there is no signaling connection control part (hereinafter referred to as SCCP) for this UE on Iu interface, it is started to establish a new SCCP connection. The establishment of SCCP connection is as follows:
I) RNC Initiates the Establishment of SCCP Signaling Connection;
When RNC receives a non-MAC (Media Access Control) message from UE for the first time and there is no Iu connection for this UE, RNC initiates the procedure of SCCP connection establishment. RNC sends a SCCP Connection Request message to CN, which includes a RANAP message in its data field.
II) CN Initiates the Establishment of SCCP Signaling Connection
CN initiates the establishment of SCCP signaling connection when executing relocation. CN initiates the establishment of Iu connection through sending a SCCP Connection Request message to RNC, which includes a RANAP message in its data field (optional).
Situations listed above are only those for SCCP connection establishment having been decided at present. And other situation will be introduced in the future.
On the occasion of normal release, the release of SCCP connection is initiated by CN. When CN finds that a signaling connection isn't needed any more, the connection will be released and CN sends a SCCP RELEASED message.
On the occasion of abnormal; both CN and RNC can initiate a release procedure.
(3) The Existing Relocation Procedure of Serving Radio Network Subsystem
The SRNS relocation procedure is described by 3GPP specification TR 23.846 v1.2.0. FIG. 2 shows the corresponding signaling flow. The detailed description for each step in the flow is as follows.
201 Source RNC decides to execute SRNS relocation procedure;
202 Source RNC sends a Relocation Demand message to the old SGSN;
203 The old SGSN forwards the Relocation Demand message to the new SGSN;
204 The new SGSN sends a Relocation Request message to the target RNC and a radio access bearer (hereinafter referred to as RAB) is established between the target RNC and the new SGSN. After the resources needed by RAB including resources of the user plane are successfully allocated,: the target RNC sends a Relocation Request Confirmation message to the new SGSN.
205 The new SGSN forwards a Relocation Response message to the old SGSN.
206 The old SGSN sends a Relocation Command message to the source RNC.
207 The source RNC starts to copy data and sends them to the target RNC through network protocol (hereinafter referred to as IP layer).
208 The source RNC sends a Relocation delivery message to the target RNC. This procedure is used to transmit SRNS Context to the target RNC and the role of SRNS converts from the source RNC to the target RNC.
209 When the target RNC receives the trigger message for relocation execution, it sends a Relocation Detecting message to the new SGSN. After that the target RNC starts to play the role of Serving Radio Network Controller (hereinafter referred to as SRNC).
210 The UE exchanges mobility related information with the target RNC, such as the new SRNC Identifier, the representation of location area and uplink user data exchanging between UE and the target RNC, etc.
211 If the SRNS relocation is a relocation occurring between different SGSNs, the new SGSN sends a Update PDP Context Request message to the corresponding GGSN after it receives the Relocation Detecting message. GGSN updates Packet Data Protocol (hereinafter referred to as PDP) context and returns back a Update PDP Context Response message. The new SGSN examines respective MBMS services in NBMS Context of UE. IF a certain service is joined by the first UE in SGSN, a GPRS Tunnel Protocol (hereinafter referred to as GTP) tunnel between SGSN and GGSN is established and MBMS Context is created in GGSN.
212 The target SRNC initiates a Relocation completion procedure after receiving a UTRAN Mobility Information Confirmation message. The new SGSN sends a Relocation completion message to notify the old SGSN of the completion of SRNS relocation procedure.
213 Release the Iu connection between the source RNC and the source SGSN and the user resources.
214 If the new Route Area Indication (hereinafter referred to as RAI) is different from that of the old, UE initiates a route location update procedure.
C1, C2 and C3 execute Customized Applications for Mobile network Enhanced Logic (hereinafter referred to as CAMEL).
Existing RANAP uses a signaling connection for each activated UE. MBMS service is a new point-to-multipoint service, whose feature is to make use of radio resources and network resources more efficiently through sharing; On Iu interface, the user plane of MBMS services is shared. If each UE uses one signaling connection, it will not only increase the traffic of the information on Iu interface and the processes on the RNC and SGSN side, but also be unable to solve completely the problem due to user mobility. In order to solve of the problem of user mobility, messages on the existing Iu interface need to be modified as well. Thus, a method for Iu interface connection oriented to MBMS service shall be proposed, which can not only make reasonable use of network resources, reduce processes on RNC and SGSN side and modifications to the existing message, but also can solve the problem of user mobility.
The existing Relocation Demand message is connection-oriented. If an user does not have other services (e.g. voice) except for receiving MBMS service, the Iu connection dedicated to the user has not been established. How to send a relocation demand message or establish Iu connection dedicated for the UE is the problem to be solved.
Since the user plane of MBMS service on Iu interface is shared, while the user plain and control plane of other services are dedicated, SRNS relocation procedure needs to be modified in this new mode;
Besides the connection method proposed in this invention (shared signaling connection is used on Iu for the same kind of MBMS service, and at the same time, dedicated Iu connection is established for the case in which other services besides MBMS service are received and the mobility of the UE occurs), there is another proposal that only shared Iu connection exists on Iu interface for UEs receiving MBMS. With respect to both these cases in which shared Iu connection exists, the method for establishing and releasing MBMS shared connection hasn't been provided in the existing SCCP connection establish procedure, and the situation for establishing shared connection shall be added to the conditions for establishing SCCP connection. Since MBMS is a new-introduced service, when the shared connection used for MBMS service shall be released is a problem unsolved in present specification.

Method for multimedia broadcast/multicast service signaling bearer connection on Iu interface


An image forming apparatus including, an image bearing member capable of having a latent image formed thereon, and a developer bearing member that bears a developer comprising a toner and a carrier, wherein a latent image formed on the image bearing member is developed by a non-contacting method under application of a vibrating electric field, so that the toner is transferred from the developer bearing member toward the image bearing member, and wherein the following relation holds: EQU 1.0.times.10.sup.-4 <t.sub.1.sup.2 /L.sub.T <1.0.times.10.sup.-3 (sec.sup.2 /m),. where t.sub.1 represents a phase period during which a toner particle of the toner is transferred from the toner bearing member to the latent image during application of the vibrating electric field and L.sub.T represents a weight average particle diameter of the toner particles.

1. Field of the Invention
The present invention relates to an image forming apparatus such as a copying machine, a printer, or a facsimile machine.
2. Discussion of the Background
A two-component developing method is well known as a remarkable developing method especially for high-speed image reproduction using powder type toner, such as electrophotography or the like. In recent years, the two-component developing method is used as a major technology in the copying machine, laser printer, etc.
In the two-component developing method, a developer is conveyed to a surface of a non-magnetizable sleeve in which magnets are mounted inside thereof, which is a developer bearing member, and the developer kept in a brush-like state (magnet-brush) contacts or is positioned adjacent to an image bearing member. Developing is implemented with a toner, which is mixed with the developer, which selectively adheres onto a latent image of an image bearing member by an electric field between the image bearing member on which a latent image is formed and the sleeve to which an electric bias is applied.
However, in a field that requires a high quality image, it is considered to be a problem that image noise, such as background fouling and/or deterioration of a sharpness of an image, due to irregular toner adherence onto the latent image, tends to appear. An image having a uniformity of dots that is formed in an interval of dozens of microns is required in order to smoothly reproduce a halftone image, for example, a printer, a digital copying machine, or the like. However, when the dot image is observed under a microscope, a large dispersion of shapes of dots or area of dots is found and toner is irregularly adhered between the dots. If this phenomenon is significant, roughness cannot be disregarded and thereby the image is less uniform.
To solve the above-described problem, a method for applying a developing bias (hereinafter called AC bias) having a vibration-component is proposed in Japanese Laid-Open Patent Publication No. 6-19213/1994, Japanese Laid-Open Patent Publication No. 7-72699/1995, Japanese Laid-Open Patent Publication No. 7-114223/1995, and the like.
However, in the conventional developing method described in each of above Publications, the quality of the image is not always improved but also deteriorates depending on a condition of applying the developing bias. This has been experimentally confirmed by the inventor. It is assumed that the movement of the toner or the carrier is affected by various factors.
Conditions such as a range of diameters of toner particles and diameters of carrier particles and a range of frequencies of the vibration bias are described in the Japanese Laid-Open Patent Publication No. 7-114223/1995, which indicates that a high frequency is preferably not less than 6000 Hz, and that the volume resistivity of the carrier is preferably not greater than 10.sup.10 .OMEGA. cm to maintain a good developing efficiency.
However, in accordance with an additional test carried out by the present inventor, it is confirmed that a phenomenon of blurring of a trailing edge portion of a solid image (hereinafter called trailing edge blurring) tends to occur in the range of the aforementioned frequency. Further, it is confirmed that, when the frequency of the vibration bias is raised up indefinitely, the effect of applying an AC bias is lost. Even though a slight improvement is confirmed by using a low resistivity carrier, a sufficient image quality is not obtained.
Various types of carriers are known, including a carrier composed of a magnetizable particle coated with resin, which is widely used in order to obtain durability (disclosed in, for example, Japanese Laid-Open Patent Publication No. 6-19213/1994). Further, a non-contacting developing method in which a magnetizable resin coated carrier is used and an AC bias (vibration bias) applied is described in Japanese Laid-Open Patent Publication No. 7-72699/1995.
However, in accordance with an additional test performed by the present inventors problems of image quality exist such that the uLiilo-rnity of the dot area is not sufficient and a phenomenon such as the trailing edge blurring is observed. The following phenomenon is surmised to be the reason that causes the problems.
If the carrier has a high electric resistance, for example, a positive-polarity charge (the opposite polarity to that of the toner) remains on a surface of the carrier when the toner has left from the carrier. On the contrary, if the carrier has a low electric resistance, the positive-polarity charge remaining on the surface of the carrier flows away in a relatively short time period. Thus, when the carrier has a high electric resistance, the charge of the opposite polarity to the toner remains on the surface of the carrier when the toner has left from the carrier. Therefore, the charge remaining on the surface of the carrier is surmised to generate a noise that abnormally attracts the toner appropriately moving towards the latent image on a photoconductive element.
There are some methods for making the magnetizable resin-coated carrier to have a low electric resistance. One of the methods that decreases the electric resistance of the carrier uses a thin coat layer and has a problem in regard to prolonging the life of the developer. As another method, a material having a low electric resistance may be used as a coat layer itself. Practically, a carrier composed of a ferrite or a magnetite as a core material, and silicone resin or the like as a coat layer in which carbon or the like is scattered can be used, since such a carrier is inexpensive and stable.
However, when the present inventor carried out developing by using the aforementioned carrier, i.e., a carrier composed of a ferrite or a magnetite core, and silicone resin or the like as a coat layer, in which carbon is scattered applying AC bias, a phenomenon that the toner image has small white flecks (hereinafter called white flecks) where the toner is removed is observed.
After repeated experiments, the inventor found that if peak-to-peak voltage of the AC bias is decreased, the less white flecks occur, and only at the toncr-adhered part of the image (the part where the potential difference from the peak potential of the AC bias is relatively large), and not when the carrier having the layer in which the carbon is not scattered is used, and the like. Consequently, it is surmised that the phenomenon of white flecks is caused by a discharge from the carbon adjacent to the surface of the carrier to the image bearing member.

Image forming apparatus and method therefor


An imaging apparatus (10) to image wise expose desired microcapsules (38) within a photosensitive media (44) with an image exposure device (12) to harden the desired microcapsules applying pressure to the exposed photosensitive media rupturing the unexposed microcapsule (40), releasing the image-forming material (48) encapsulated within to form an image on the photosensitive media, the exposure device having a molded lenslet array (14) with a printed lens mask improving channel cross talk, aberrations, and reducing flair.

Image exposure devices having light emitting elements have been used in imaging equipment to expose images on photosensitive media. Such a device is described in U.S. Pat. No. 6,034,712, which uses an array of light emitting light elements disposed within recesses formed in a substrate with a pinhole mask to expose an image on photosensitive media. The photosensitive media may be of the type having a plurality of microcapsules, with an image-forming material encapsulated within the microcapsules.
To form an image on a photosensitive media having microcapsules, a multiple channel image exposure device may be used to expose desired microcapsules with at least one of the multiple light emitting elements. Image wise exposure by the exposure device hardens the desired microcapsules such that when pressure is applied by means of a microcapsule-rupturing device only the unexposed microcapsules are ruptured. The ruptured microcapsules release an image-forming material encapsulated within to form an image within the photosensitive material. Similar imaging forming equipment is described in U.S. Pat. Nos. 4,440,846 and 4,339,209.
Image exposure devices having molded lenslets generally have a mask to reduce channel cross talk, aberrations, and flair. Depending on the application, the mask can become very important to the image quality of a completed image. Typically the mask is placed in the light path of the exposure device. Accuracy of the location and features of the mask may be required to be within a few microns to prevent blocking the light source or forming image artifacts in an image formed on the photosensitive media due to the alignment or accuracy of the mask. Alignment can become complicated and expensive as the number of imaging channels increases. Thus, there is a need for improved image quality and lower cost by improving the fabrication and alignment accuracy of a mask used in a multiple channel image exposure device.

Method of manufacturing a molded lenslet array


The implementation method for an identification system using dynamic barcode entails description for a system that comprises a smartphone, a barcode information access device on the merchant side, and a server of an identification agency. The implementation method described includes downloading a mobile application (app) for smartphone, and utilizing the app to upload identification information to server of the identification agency. When a user needs to be identified during a transaction, the aforementioned app is used to display two barcodes on the smartphone: one barcode represents the user's identification, and the other is a dynamic one that corresponds to the user's identification information and changes after a given time period. When both barcode information are read by barcode reader and send to the server of the identification agency, the said agency could easily compare its own information with the dynamically generated barcode information, which helps to distinguish whether the user is the original registrant.

Field of the Invention
This invention pertains to an identification barcode that contains identification information that is generated by an application of a smartphone, as well as a dynamic barcode that corresponds to identification information after a given period of time; the aforementioned barcodes are read by a barcode reader and sent to a server of an identification agency to be compared. The above process entails the implementation method for an identification system using dynamic barcode.
Brief Description of the Prior Art
If all transactions are conducted through the medium of cash, it is troublesome and time-consuming. Hence, in recent years, credit card, debit card, and electronic ticket are used instead; however, this gives rise to the problems of forgery and theft. In other words, the business world has yet to completely solve the need for a convenient and safe identification solution. In recent times, smartphones are gaining wider popularity and naturally people would like to use their smartphones as a tool to pay, namely using smartphones as electronic wallets and mobile payment. The core issue is also how to provide a convenient and safe user identification method. The industry has long set its eyes on NFC (Near Field Communication) as the mode of data communication and identification, but smartphones currently have three operating systems: iOS, Android and Windows, and this cause tremendous obstacle in reading for the readers. For instance, there isn't a NFC reader that can both scan Apple Pay and Google Wallet. As there are few customers initially, business owners are less willing to purchase additional NFC readers for each digital payment, and this begins a vicious cycle of less customers applying for electronic wallet and mobile payment as fewer businesses utilize NFC readers. In addition, smartphone companies such as Apple, telecommunication companies, and banks all want to gain a share of the electronic wallet market, but business owners are certainly unwilling to spend extra money on the procurement of NFC readers. The simplest solution to this problem is to adopt linear CCD (charge-coupled device) or CMOS (complementary metal-oxide-semiconductor) reader devices that all businesses have, which can directly scan barcode from customers' smartphones without the need for additional procurement. The barcode represents the customer's identification, and thus achieve our intended objective. However, if we only stop at that, the problem of forgery may happen frequently. Current methods employed in the market use encryption, and even barcodes can be encrypted by changing its shape. Since barcodes are password protected, the system manager will know how to decrypt the passwords. As time progresses, even though passwords are stored in the identification system, the likelihood that they are decrypted by unwanted parties can increase exponentially.
U.S. Pat. No. 8,931,703 "Payment cards and devices for displaying barcodes" is to display barcode on a single card, and its functionality pales in comparison with a smartphone. Further, cost is incurred in buying a costly electronic card, which takes up space to carry. It is unlikely to be accepted by consumers in general.
Other U.S. Pat. Nos. 8,600,883 and 8,862,513, both with same title "Mobile barcode generation and payment", involves the entry of mobile phone number and a fixed password or PIN (Personal Identification Number), which will then generate a barcode through a Payment Provider to determine the user's identification or card number. However, a fixed password or PIN is very vulnerable and fails to meet security requirements.

Implementation method for an identification system using dynamic barcode

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