Abstract: WDM optical transmission equipment with redundant configuration includes a plurality of transmitters. Each transmitter includes active and standby panels including active and standby optical transmission circuits respectively having active and standby attenuators for controlling an attenuation amount of each output of the active and standby optical transmission circuits; and a coupler combining the outputs of the active and standby attenuators.

Abstract: An information write/read head writes or reads information on or from recording tracks by the heat-assisted system. The information write/read head includes a magnetic head provided in such a manner that a longitudinal direction of a magnetic gap crosses a scanning direction. Further, the information write/read head includes an aperture slit having a length of not less than a diffraction limit of a light beam, and a width shorter than the diffraction limit in the direction orthogonal to the recording track, which is formed in such a manner that the longitudinal direction thereof is aligned in a scanning direction of the recording track.

Abstract: A thermal air flow rate measuring apparatus of great precision is disclosed. In the thermal air flow rate measuring apparatus, sensitivity is enhanced by sensors having different output characteristics and an operating means employing a digitized signal, and the sensitivity and temperature can be corrected easily depending on the flow direction of fluid.

Abstract: An optical sample includes a mask layer made of a material in which an aperture is produced by a chemical change, which is reversible, upon application of heat or light, and a recording layer provided at a position where an evanescent field produced in the aperture when light is applied to the mask layer can reach. Since the aperture is produced in the mask layer by a chemical change, it can be opened and closed at a high speed and hence a high-speed transfer of information can be achieved.

Abstract: A magnetic recording medium, which includes a substrate and an amorphous magnetic layer, made of an amorphous magnetic material, for magnetic recording of data, is provided with an underlayer between the substrate and the amorphous magnetic layer, the underlayer being made of amorphous metal element, and having a mean thickness of 10 nm or less. In this manner, movement of magnetic domain walls of the amorphous magnetic layer is effectively limited by minute irregularities on a surface of the underlayer. This realizes a stable formation of a minute recording mark. This realizes recording having a sufficient signal quality, even when the high-density recording is performed by forming such a minute recording mark that a shortest length of the recording mark is less than 100 nm. Moreover, this allows the magnetic recording medium to have a simplified layer structure.

Abstract: An optical amplifying apparatus has a plurality of pumping sources generating pumping light beams at different wavelengths, a Raman amplification medium receiving the pumping light beams from the pumping sources to amplify a main signal light beam by using stimulated Raman scattering phenomenon due to the pumping light beams, a rare-earth-doped optical amplification medium receiving the main signal light beam amplified by the Raman amplification medium to further amplify it, and a pumping light introducing means introducing a part or all of a pumping light beam at a specific wavelength of the pumping light beams as a pumping light beam for the rare-earth-doped optical amplification medium to the rare-earth-doped optical amplification medium. The optical amplifying apparatus in a smaller size and with less fluctuation in the optical output power can readily send monitoring control information irrespective of presence of the optical input power.

Abstract: A cartridge includes upper and lower half segments butting against each other and containing a disk, a shutter provided on one side of the cartridge half segments for exposing or alternatively enclosing the disk, and a torsion spring attached to the shutter for biasing the shutter in a closing direction. An insertion opening is formed in a side portion of the cartridge for permitting insertion of the torsion spring therethrough from outside, and a protective wall is provided upright between the insertion opening and the disk to define a space by the wall and the upper half segment. The space is so sized as to permit the torsion spring to pass therethrough while leaving a small clearance, with legs thereof directed laterally.

Abstract: Featured is a recording and reproducing method of a magneto-optical recording medium including a recording layer for recording thereon information magneto-optically and a readout layer which has in-plane magnetization at room temperature and where a transition occurs from in-plane magnetization to perpendicular magnetization as temperature raises. The method includes projecting a light beam onto such a magneto-optical recording medium so as to form a perpendicularly magnetized area in the readout layer by duplication of the magnetization of said recording layer to the area. In further embodiments, the recording medium further includes an intermediate layer made of non-magnetic film formed between the readout and recording layers and the readout and recording layers are composed of rare-earth transition metal alloys such as TbFeCo (recoding layer) readout layer, made of GdFeCo (readout layer).

Abstract: An optical device and a recording medium are provided with a recording layer for recording information by radiation of light, and a mask layer which is formed closely to the recording layer, reduces its transmittance of light due to light or heat, and transmits light to the recording layer by using a near-field effect. An optical reproducing and recording method includes the steps of: emitting a laser beam onto the mask layer, generating a near field around an area of the mask layer that has transmittance being reduced by the laser beam, and reproducing or recording optical information in the recording layer by interaction between the near field and the recording layer. With this method, it is possible to provide the optical device, recording medium, and optical reproducing and recording method that can realize a high S/N ratio upon reproducing and recording and that can readily form a recording mark.

Abstract: A communication apparatus includes a transmitter and a receiver for communicating communication data containing transmission data transmitted from an operator; and a data (physical data of his/her surrounding environment) analyzer for outputting a mental state and/or a physiological condition of the operator by estimating it based on the communication data. The communication apparatus enables smooth communication between a sending end and a receiving end.

Abstract: Communication system of a group robot system is made hierarchical, having a base station as an uppermost layer and a plurality of layers formed by a plurality of sensing robots, and the plurality of sensing robots are controlled such that a sensing robot belonging to an upper layer of the hierarchical structure has higher sensing resolution than a sensing robot belonging to a lower layer of the hierarchical structure. Thus, a group robot system capable of efficiently searching for an object can be obtained.

Abstract: A magneto-optical recording medium is composed of a base which has a property that a light can be transmitted therethrough, a readout layer formed on the base, which has in-plane magnetization at room temperature, whereas, a transition occurs from in-plane magnetization to perpendicular magnetization as the temperature thereof is raised and a recording layer formed on the readout layer for recording information magneto-optically. A recording and reproducing method and the optical head are designed for the magneto-optical recording medium. By the recording and reproducing method using the optical head, information recorded at high density can be reproduced.

Abstract: The present invention aims at providing a technique capable of supervising and controlling optical repeaters, without affecting transmission characteristics and wavelength bands of signal lights, by utilizing the Raman effect. To this end, the present invention provides a supervisory controlling system of an optical repeater, in an optical amplifying-and-repeating transmission system for amplifying and repeatingly transmitting signal light propagated through an optical transmission path by the optical repeater, wherein the supervisory control signal light is amplified due to the Raman effect by the signal light acting as excitation light in an optical transmission path (Raman amplifying medium), to thereby supervise and control the optical repeater in accordance with the thus Raman amplified supervisory control signal light.

Abstract: A disc cartridge includes a disc casing having a disc chamber defined therein for rotatably accommodating the recording medium. The disc casing has a sensor hole and a slot defined in first and second wall portions of the casing that are opposed to each other. A safety device is disposed within the disc casing for preventing information recorded on the erasable recording medium from being erased inadvertently. The safety device includes a bearing bushing integral with the first wall portion, and a switching element connected at one end rotatably with the bearing bushing for angular movement between first and second operative positions. The sensor hole is adapted to be closed by the switching element when the latter is angularly moved to the first operative position.

Abstract: A magnetic recording medium, which includes a substrate and an amorphous magnetic layer, made of an amorphous magnetic material, for magnetic recording of data, is provided with an underlayer between the substrate and the amorphous magnetic layer, the underlayer being made of amorphous metal element, and having a mean thickness of 10 nm or less. In this manner, movement of magnetic domain walls of the amorphous magnetic layer is effectively limited by minute irregularities on a surface of the underlayer. This realizes a stable formation of a minute recording mark. This realizes recording having a sufficient signal quality, even when the high-density recording is performed by forming such a minute recording mark that a shortest length of the recording mark is less than 100 nm. Moreover, this allows the magnetic recording medium to have a simplified layer structure.

Abstract: Featured is a recording and reproducing method for recording and reproducing information on and from a recording medium. The medium includes a base having a property that a light can be transmitted therethrough, a readout layer formed on the base, which has an in-plane magnetization at room temperature, whereas, a transition occurs from in-plane magnetization to perpendicular magnetization as temperature rises and a recording layer formed on said readout layer for recording thereon information magneto-optically. A groove for guiding a light beam is formed on a readout layer side of the base and a groove width is set substantially equal to a land width formed between grooves. The recording layer on the grooves and the recording layer on lands are used in recording and reproducing information.

Abstract: By employing command value signals for controlling the opening timing of an exhaust valve or an intake valve and means for measuring flow rates of an intake air of a flow direction which flows through an intake manifold of an internal combustion engine, an air flow rate corresponding to the command value signal is measured. A valve mechanism includes the intake valve and the exhaust valve for each cylinder of the internal combustion engine and is controlled by a valve control means for controlling the valve mechanism. A failure diagnosis of an operating status of the valve mechanism can be performed.