Abstract: A Group III-nitride semiconductor device that has a low voltage-drop p-contact and comprises a substrate layer, a metal electrode and an intermediate layer sandwiched between the substrate layer and the metal electrode. The substrate layer is a layer of a p-type Group III-nitride semiconductor, and the intermediate layer includes a Group III-nitride semiconductor in which atoms of a Group V element other than nitrogen have been substituted for a fraction of nitrogen atoms. The Group III-nitride semiconductor device is made by providing a substrate including a p-type Group III-nitride semiconductor having an exposed surface. Atoms of a Group V element other than nitrogen are substituted for a fraction of the nitrogen atoms of the p-type Group III-nitride semiconductor to form an intermediate layer extending into the p-type Group III-nitride semiconductor from the exposed surface. Metal is then deposited on the exposed surface to form an electrode in electrical contact with the intermediate layer.

Abstract: A gas or liquid detector that includes a capacitative sensor and a capacitance detector. The capacitative sensor includes a first electrode and a second electrode separated from one another, and additionally includes Debye elements extant in the liquid adjacent such portions of the electrodes that are in contact with the liquid. The Debye elements each include a Debye capacitor with an associated shunt conductor. The shunt conductor has an exponentially-increasing conductance versus voltage characteristic. The Debye element adjacent the first electrode and the Debye element adjacent the second electrode are connected in series by conduction through the liquid. The Debye element adjacent at least the first electrode has a substantially greater capacitance than the capacitance between the electrodes absent the Debye elements. The capacitance detector is connected to the capacitative sensor and measures the capacitance of the capacitative sensor by applying an alternating voltage between the electrodes.

Abstract: The frequency standard comprises a quantum absorber, a source of incident electro-magnetic radiation, a detector, a frequency difference controller, a spectrum controller and a frequency standard output. The quantum absorber has transitions including a first transition between a first lower quantum state and an upper quantum state, and a second transition between a second lower quantum state and the upper quantum state. The first transition and the second transition have energies that correspond to frequencies of &ohgr;1 and &ohgr;2, respectively. The lower quantum states differ in energy by an energy difference subject to a total a.c. Stark shift. The source of incident electro-magnetic radiation is arranged to irradiate the quantum absorber. The incident electro-magnetic radiation includes main frequency components at frequencies of &OHgr;1 and &OHgr;2, equal to &ohgr;1 and &ohgr;2, respectively, and additionally includes additional frequency components collectively having a spectrum.

Abstract: A switching device includes a substrate, a first waveguide segment, a second waveguide segment, a heating device, a liquid, and a pressure controlling mechanism. The substrate is coupled to the first waveguide segment and the second waveguide segment, and the substrate includes a chamber that separates the first waveguide segment from the second waveguide segment. The liquid is disposed in the chamber and is responsive to the heating device. The pressure controlling mechanism controls a pressure in the chamber such that inadvertent bubbles are prevented from forming between the first waveguide segment and the second waveguide segment.

Abstract: A jack socket that comprises a body that defines an axial bore adapted to receive a phone jack, and an annular groove at each of at least two axially-spaced locations along the axial bore. Each annular groove is concentric with, perpendicular to, and faces into, the axial bore. The jack socket additionally comprises an annular spring member corresponding to each annular groove. The annular spring member includes a radially-outer portion housed in the annular groove and a radially-inner portion extending into the axial bore. Finally, the jack socket comprises an electrical connection through the body to each annular spring member.

Abstract: The document display system comprises a first character shape generator, a first display and a first transmitter in a first terminal device; and a first receiver, a second character shape generator and a second display in a second terminal device. The first character shape generator generates the character shapes of characters constituting at least part of a document. The character shapes are generated in response to skeleton information and in response to shape generation information that includes information representing a typeface. The first display displays the characters with the character shapes generated by the first character shape generator so that the at least part of the document is displayed set in the typeface. The first transmitter transmits character information indicating the skeleton information for each of the characters. The first receiver receives skeleton information for each of the characters.

Abstract: A compact optical imaging system that transmits light received from an object located at an image plane to an exit pupil to form an image comprises a first prism, a second prism, a converging reflective element, and a converging transmissive element. The first prism includes a first face, a second face, and a third face that faces the image plane. The included angle between the first face and the second face of the first prism is .alpha.. The second prism includes a first face facing the exit pupil and substantially parallel to the first face of the first prism, and a second face adjacent the second face of the first prism. The converging reflective element is adjacent the first face of the first prism. The converging transmissive element is on or adjacent the first face of the second prism. The included angle .alpha.

Abstract: Character recognition with an improved recognition ratio is provided without requiring special operations to be performed before character recognition is performed. A preliminary character recognition operation is performed in which the feature vector of an input character is compared to a recognition dictionary that contains a reference vector for each category. The candidate category to which the input character belongs is determined, and the feature vector and recognition result for each input character is saved. The input characters judged to have been recognized with high reliability are selected with reference to their recognition results. The feature vector of each selected input character is used to predict a writer-specific feature vector of a category different from the candidate category to which the selected input character belongs.

Abstract: A multilevel data storage system that comprises an interface, an upper-level storage device, a lower-level storage device and first and second compression state modifying engines. Data are transferred through the interface in a first compression state. Data are stored in the upper-level storage device in a second compression state that is higher than the first compression state. Data are stored in the lower-level storage device in a third compression state that is lower than the second compression state. The first compression state modifying engine is located between the interface and the upper-level storage device. The second compression state modifying engine is located between the upper-level storage device and the lower-level storage device.

Abstract: A miniature three-port optical circulator that comprises a first input/output (I/O) port, a second I/O port complementary to the first I/O port, and a second walk-off crystal located between the first I/O port and the second I/O port. The first I/O port includes a light coupling assembly, a first walk-off crystal and a split polarization rotator arranged in order along the optical axis. The light coupling assembly comprises a capillary and two optical fibers. The optical fibers are secured side-by-side in the bore of the capillary. The optical fibers each have a diameter of one half of the diameter of the bore. The cores of the optical fibers are separated from one another in a separation direction by a separation distance. The first walk-off crystal is located to receive the light beams and has a first walk-off direction perpendicular to the separation direction. The split polarization rotator is mounted adjacent the first walk-off crystal and has a positive half and a negative half.

Abstract: A system information management unit obtains system information from end systems or media data conversion units and sets end system media data compatibility conditions. The media data conversion units obtain this system information from the system information management unit. When media data are transmitted between the end systems, the media data are first converted in accordance with the system information and then sent to receiving end systems.

Abstract: The hologram card generates a hologram image in response to an illumination light beam. The hologram card comprises a substrate of a first plastic material having a first refractive index. The substrate has a contoured surface. The contoured surface is formed to include localized topological features constituting a diffractive optical element. The diffractive optical element is structured to generate a hologram image when illuminated by the illumination light beam. The hologram card also comprises a protective layer of a second plastic material having a second refractive index that differs from the first refractive index by less than 0.2. The protective layer covers the contoured surface of the substrate. The protective layer is chemically bonded to, and directly contacts, at least the topological features constituting the diffractive optical element.

Abstract: An illumination system that comprises a light source, and, disposed in an optical path between the light source and the surface, converging imaging optics, and a diffractive array generator. The diffractive array generator preferably includes a two-dimensional periodic array of multi-level topological features.

Abstract: Useful life extension for a data storage system in which either or both of read/write probes and storage areas are components subject to wear caused by the access operations. An access counter counts an access count for each component subject to wear. A data exchange module operates in response to the access count for one of the components subject to wear reaching a first threshold to perform a data exchange in which data stored in a first storage area are exchanged with data stored is a second storage area. When the components subject to wear are the storage areas, the first storage area is the storage area whose access count reached the first threshold value, and the second storage area is a storage area whose access count is less than the first threshold value.

Abstract: An electrostatic actuator having a first member and a second member. The first member has a first opposed surface that includes an array of driven electrodes. The driven electrodes have a pitch p.sub.r. The second member has a second opposed surface and includes an array of drive electrodes. A support positions the first member adjacent the second member with the first opposed surface spaced apart from the second opposed surface by a spacing d. The ratio of the spacing and the pitch should be less than eight, and is preferably less than 2.25. The support permits the first member to move relative to the second member, or vice versa. A voltage source establishes a substantially alternating voltage pattern on the array of driven electrodes.

Abstract: A compact, 2.times.n(n=1 or 2), polarization-independent optical component that comprises a first I/O port, a second I/O port and a polarization-changing optical element located between the first I/O port and the second I/O port. The second I/O port is optically aligned with the first I/O port. The first I/O port includes a serial arrangement of a first opposed walk-off crystal pair and a second opposed walk-off crystal pair, each opposed walk-off crystal pair comprising two walk-off crystals having opposite walk-off directions, the walk-off directions of the walk-off crystals of the first opposed walk-off crystal pair defining a first direction of rotation, the walk-off directions of the walk-off crystals of the second opposed walk-off crystal pair defining a second rotational direction, opposite to the first rotational direction.

Abstract: A delta-modulated magnitude amplifier is used to amplify the magnitude component of an RF power amplifier that employs envelope elimination and restoration. The delta-modulated amplifier introduces a smaller amount of non-linearity than traditional approaches, which are based upon pulse-width modulation. The disclosed technique can be implemented using switched-capacitor circuits in a standard MOS technology with only two external components, i.e., an inductor and a capacitor. Thus, the disclosed technique allows the implementation of an efficient and yet linear RF power amplifier using low-cost MOS technology.

Abstract: A pressure regulator that sets the pressure of a liquid to a predetermined pressure differential below a reference pressure, such as atmospheric pressure. The pressure regulator comprises a liquid delivery channel and a capillary array. The liquid delivery channel includes a liquid input and a liquid output. The liquid flows through the liquid delivery channel from the liquid input to the liquid output. The capillary array is composed of ones of an elongate capillary. The capillary includes a first end in fluid communication with the liquid delivery channel and a second end in pressure communication with a source of the reference pressure. The liquid flows through the first end into the capillary to form a liquid surface in the capillary. The second end is remote from the first end.

Abstract: A micro needle probe apparatus that includes a probe and its associated electronic circuit. The electronic circuit is formed in a substrate and includes at least one metal interconnection layer. The probe is cantilevered over the electronic circuit and is composed of a metal probe arm, a support post that anchors one end of the probe arm to the substrate, and a micro needle mounted adjacent the moveable end of the probe arm. The probe apparatus may be used as the read/write mechanism of the moving-medium type memory device.

Abstract: An organic electroluminescent device that comprises a substrate, a first conductive layer on the substrate, an electron-transporting and light-emitting layer, a second conductive layer adjacent the electron-transporting and light-emitting layer and remote from the first conductive layer, and a hole-conducting layer sandwiched between the first conductive layer and the electron-transporting and light-emitting layer. The hole-conducting layer comprises a poly(arylamine) including at least one compound of formula (I): ##STR1## In this: R is independently in each occurrence a C.sub.1-24 hydrocarbyl, hydrocarboxyl, hydrothiocarboxy, hydroarylcarboxy, or hydrothioarylcarboxy; Ar.sub.1 and Ar.sub.2 are independently in each occurrence a C.sub.6-18 aryl moiety optionally substituted with one or more C.sub.