Abstract: A navigation system includes a GPS receiver for receiving radio waves transmitted from multiple GPS satellites and producing a measured position, an error-range setting unit for setting an estimated error range in which a measured position at the time of current positioning by the GPS receiver is included, a relative-position determining unit, and a position correcting unit. The relative-position determining unit and the position correcting unit correct the measured position by using an actual measured position, when the actual measured position produced by the GPS receiver at the current positioning time is in the estimated error range. The relative-position determining unit and the position correcting unit correct the measured position in accordance with a relative positional relationship between the actual measured position and the estimated error range, when the actual measured position is out of the estimated error range.

Abstract: A method for communication among mobile units and vehicular communication apparatus make it possible to automatically establish connection with a party who can provide required information on the basis of an environment or condition change of a driver or a vehicle or in response to a driver's request so as to permit communication with the party. An inter-vehicle communication apparatus of a vehicle acquires information from other mobile units through physical networks while it is moving or stopped, and registers, in a member table, mobile units satisfying predetermined conditions on the basis of the acquired information as the members of different virtual logic networks according to the conditions. In such a state, the inter-vehicle communication apparatus selects one virtual logic network from among a plurality of virtual logic networks on the basis of an environment or condition change of a driver or a vehicle or in response to a driver's request so as to permit communication with the party.

Abstract: A navigation system includes a GPS receiver for receiving radio waves transmitted from multiple GPS satellites and producing a measured position, an error-range setting unit for setting an estimated error range in which a measured position at the time of current positioning by the GPS receiver is included, a relative-position determining unit, and a position correcting unit. The relative-position determining unit and the position correcting unit correct the measured position by using an actual measured position, when the actual measured position produced by the GPS receiver at the current positioning time is in the estimated error range. The relative-position determining unit and the position correcting unit correct the measured position in accordance with a relative positional relationship between the actual measured position and the estimated error range, when the actual measured position is out of the estimated error range.

Abstract: In a message processing system, a plurality of vehicles or other locations are equipped with message processing devices and transmit and receive a message. The message has a header and a body. The header includes a valid duration and/or a valid zone specified by various methods, and an optional flag set when the message reaches the valid zone. The body includes data to be transmitted and read out for predetermined processing. When receiving the message, the message processing device may transfer the message if the message is within the valid duration and the device is within the valid zone, or if the message is within the duration and the device is not within the valid zone but the flag is not set. When transmitting a message, the message processing device sets the valid duration and/or zone and may include the flag for the message header, and generates the data to be transmitted for the message body.

Abstract: In a message processing system, a plurality of vehicles or other locations are equipped with message processing devices and transmit and receive a message. The message has a header and a body. The header includes a valid duration and/or a valid zone specified by various methods, and an optional flag set when the message reaches the valid zone. The body includes data to be transmitted and read out for predetermined processing. When receiving the message, the message processing device may transfer the message if the message is within the valid duration and the device is within the valid zone, or if the message is within the duration and the device is not within the valid zone but the flag is not set. When transmitting a message, the message processing device sets the valid duration and/or zone and may include the flag for the message header, and generates the data to be transmitted for the message body.

Abstract: A method for communication among mobile units and vehicular communication apparatus make it possible to automatically establish connection with a party who can provide required information on the basis of an environment or condition change of a driver or a vehicle or in response to a driver's request so as to permit communication with the party. An inter-vehicle communication apparatus of a vehicle acquires information from other mobile units through physical networks while it is moving or stopped, and registers, in a member table, mobile units satisfying predetermined conditions on the basis of the acquired information as the members of different virtual logic networks according to the conditions. In such a state, the inter-vehicle communication apparatus selects one virtual logic network from among a plurality of virtual logic networks on the basis of an environment or condition change of a driver or a vehicle or in response to a driver's request so as to permit communication with the party.

Abstract: A learning support system detects an input operation by each user, whenever he operates his terminal apparatus, stores a learning history of each user whenever input operation is detected, learning history including input operation and first time period which is time period from starting time when he starts learning until when input operation is detected, to obtain set of learning histories corresponding to each user and being stored from starting time until when he finishes to learn learning material, retrieves, whenever predetermined time period elapses from starting time corresponding to first user, one learning history, to obtain retrieved learning history whose first time period is equal to second time period from starting time corresponding to first user until when predetermined time period elapses, from sets of learning histories corresponding to second user, and displays retrieved learning history on first user's terminal apparatus.

Abstract: The degree of association between each document specified by each of the URLs included in the document transferred from a document providing system to a document requesting system and the document specified by the preceding document request is determined on the basis of the depth of link between the document specified by the preceding document request and each document specified by each URL or the degree of similarity between the contents of those documents. Using the thus obtained degree of association, a document to be received in advance is specified in the document requesting system. Consequently, even when a document having a lot of URLs is requested first or when each of the documents requested as related documents further includes a URL specifying another document, the document requesting system can specify documents closely related to the first requested document.

Abstract: An information communication system in which main data and restore-date used for restoring the main data are written in a memory card by a first information apparatus. The main data and the restore-data are read from the memory card by a second information apparatus. On the basis of the restore-data, the main data is restored by the second information apparatus. The main data, thus restored is processed and/or output by the second information apparatus.

Abstract: An encoder for measuring devices having a code plate including binary grating patterns arranged in a given regular fashion and forming a first scale, a linear sensor including photodiode elements arranged with fixed intervals and forming a second scale disposed in parallel with the code plate, and processor means for absolute-interpolating one pitch of the first or second scale on the basis of reading data or information obtained from the linear sensor corresponding to a relative position of the patterns to the elements.When the number of the scale divisions of the first scale within a fixed range is N, the number of the scale divisions of the second scale is N+1. Accordingly, when the first scale is a main scale, the second scale is a vernier scale. The processor means detects a phase inverting point corresponding to the interpolation point on the basis of the reading data. The processor means performs the absolute interpolation by detecting the phase inverting point.

Abstract: An encoder having an optical measuring part establishing a vernier relationship between a code plate and a line sensor, and counters for obtaining a course reading from time serial output signals of the line sensor and a fine reading from the vernier relationship. Correction data including a change component in a magnification of a lens system are obtained from a counter. The correction data and the fine reading are supplied to a converting circuit to provide a corrected fine reading.

Abstract: In an optical apparatus for inspecting optical defects, a laser beam generated from a laser unit is converted by a collimator lens into a light beam having a suitable diameter. An X-Y scanner for two-dimensionally scanning the light beam is situated at a forward focal point of a scanning lens. The light beam passed through the scanning lens is converged substantially in parallel with an optical axis of the scanning lens and is reflected by a semi-transparent mirror and is vertically projected onto a flat surface to be inspected of an article situated substantially at a backward focal point of the scanning lens. Thus, on the surface to be inspected of the article there is given a projected beam spot having a larger diameter than that of the relevant circle of least confusion. The light rays reflected by the article surface to be inspected are converged by a converging lens the forward focal point of which is located on the said article surface.

Abstract: An apparatus for detecting the defects composed of non-linear components of a subject pattern, includes a laser source for illuminating the subject pattern by a laser beam, a Fourier-transform lens for projecting an information light from the pattern through a spatial filter onto a screen. The filter is placed on the Fourier-transform plane of the Fourier-transformed information light for intercepting the coherent light having information on linear components, the filter having arm sections extending correspondingly to the linear components of said normal pattern, the outer periphery of said arm sections including curved sections of a circular or elliptical shape protruding toward the intersecting point of the arms.

Abstract: An automatic focusing apparatus includes a lens for leading a laser beam onto a sample surface at a predetermined incident angle, a beam splitter to divide the reflected beam from the sample surface in accordance with the vertical shift thereof, a pair of photo diodes to respectively receive the divided beams and produce electric signals, a differential amplifier to produce a differential signal between the electric signals and a mechanism to vertically shift the stage by means of the differential signal to automatically focus a lens system on said sample surface.

Abstract: An apparatus for detecting the defects composed of non-linear components of a subject pattern, includes a laser source for illuminating the subject pattern by a laser beam, a Fourier-transform lens for projecting an information light from the pattern through a spatial filter onto a screen. The filter is placed on the Fourier-transform plane of the Fourier-transformed information light for intercepting the coherent light having information of the linear components, the filter having arm sections extending correspondingly to the linear components of said normal pattern, the outer periphery of said arm sections including curved sections protruding toward the intersecting point of the arms.

Abstract: An optical system for a object illuminating light source includes a phase plate for giving "0"-relative phases or ".pi."-relative phases to the incident light fluxes to cancel with respect to one another all the interference fringes except for those two light fluxes incident to define a maximum angle.

Abstract: Two kinds of light sources, one of which emits a coherent light and the other of which emits incoherent light, are provided. The coherent light and incoherent light respectively emitted from the two different kinds of light sources, proceed on the same optical axis. A photomask, such as for an integrated-circuit, or other objects, which have linear straight line features and nonlinear defects, are simultaneously illuminated by the coherent light and incoherent light.The two kinds of light which pass through the photomask or other objects are transformed into a Fourier-transform pattern by a transform lens. A spatial filter, having a plurality of arms which extend in predetermined directions from the center thereof, is provided on the focal plane of the transform lens.The spatial filter suppresses the passing of coherent light having information of the linear straight line features. The coherent light which has information of the defects of the photomask is not suppressed by the spatial filter.

Abstract: An optical readout device including a gas discharge display panel with spot light sources each selectively energizable to illuminate the corresponding character pattern, a memory plate which stores the character patterns, and also including an image pickup device which detects the light distribution of the character pattern illuminated with the spot light of the said gas discharge display panel.