Abstract: A logical operation element and logical operation circuit are provided that are capable of high speed and a high degree of integration. A logical operation circuit has a construction wherein, in a logical operation element, the anodes of first and second field emission type microfabricated electron emitters are put at the same potential and two or more signal voltages are input to gate electrodes corresponding to these emitters. A NOR element so arranged that when a high potential input signal is input to either of the two lines, electron emission occurs from the emitters and the potential of said anodes is lowered, and a NAND element wherein the cathodes of the first and second field emission type microfabricated electron emitters are connected in series, two signal voltages are applied to the gate electrodes corresponding to the first and second emitter and the anode potential of the second emitter is lowered when the two input signals are high potential are employed.

Abstract: An optical waveguide (optical fiber, for example) having low transmission loss, nonlinearity, and chromatic dispersion and facilitating the termination work for its end portions. An optical fiber 10 comprises a main medium 11 in which minute regions 12 composed of a multitude of submedia are distributed. The main medium 11 is made of silica glass, for example. The submedium in each minute region 12 is formed by a vacuum or a gas, such as an inert gas or air. The submedia have a refractive index smaller than that of the main medium 11. Each minute region 12 does not extend along the axis C.

Abstract: A logical operation element and logical operation circuit are provided that are capable of high speed and a high degree of integration. A logical operation circuit has a construction wherein, in a logical operation element, the anodes of first and second field emission type microfabricated electron emitters are put at the same potential and two or more signal voltages are input to gate electrodes corresponding to these emitters. A NOR element so arranged that when a high potential input signal is input to either of the two lines, electron emission occurs from the emitters and the potential of said anodes is lowered, and a NAND element wherein the cathodes of the first and second field emission type microfabricated electron emitters are connected in series, two signal voltages are applied to the gate electrodes corresponding to the first and second emitter and the anode potential of the second emitter is lowered when the two input signals are high potential are employed.

Abstract: An optical waveguide (optical fiber, for example) having low transmission loss, nonlinearity, and chromatic dispersion and facilitating the termination work for its end portions. An optical fiber 10 comprises a main medium 11 in which minute regions 12 composed of a multitude of submedia are distributed. The main medium 11 is made of silica glass, for example. The submedium in each minute region 12 is formed by a vacuum or a gas, such as an inert gas or air. The submedia have a refractive index smaller than that of the main medium 11. Each minute region 12 does not extend along the axis C.

Abstract: A satellite 10 in the sky has an imaging radar and a captured image data transmitting means, and captures an image of a predetermined subject area A including roads R. According to the captured image data concerning the subject area A, a traffic control section 21 grasps the state of traffic in the subject area A, and estimates a state of congestion according to thus grasped state of traffic. Also, according to thus estimated state of congestion, the traffic control section 21 sets parameters such as on/off times of signals. Thus set parameters are sent from the traffic control section 21 to their corresponding signals. The on/off of each signal is controlled according to the set parameters. Hence, the state of traffic in a wide area can be grasped quite accurately, and traffic can be controlled according to thus grasped state of traffic.

Abstract: An optical information reading device for character recognition and processing having an array of luminous diodes to illuminate the material to be read. A sensor transmits received data signals to a pattern indentification circuit. The signals are also transmitted to a light control circuit to vary the illumination to the array to provide uniform lighting of the characters to be read.

Abstract: A method of manufacturing an O-ring type optical waveguide wherein a layer of fused silica is formed on the smooth cylindrical surface of an elongated member of fused silica and thereafter a thin layer of doped fused silica having an index of refraction greater than that of said fused silica is formed over said layer of fused silica. A second layer of fused silica is then formed over the layer of doped fused silica and the composite structure is heated to its drawing temperatures and drawn to reduce the cross sectioned area thereof to form an optical waveguide having a cylindrical layer of higher refractive index interposed between a core and an outer cylindrical layer of lesser refractive index.

Abstract: An O-type optical waveguide comprising a rod of fused silica having formed thereon a layer of doped fused silica having an index of refraction which is greater than that of the rod, and an outside layer of fused silica over the layer of doped fused silica. The surfaces between of doped silica, having the higher refractive index, and the low adjacent layers between which it lies are extremely smooth and clean or free from foreign particles thereby preventing scattering loss due to the inclusion of foreign particles.

Abstract: A communication system between mobile and wayside stations wherein the mobile stations are traveling on a track which is divided into sections by means of an open-type transmission line paralleling the track. A frequency selection and conversion device for each section of transmission line or track is connected to the transmission line to define the length of each section. A series of lower frequency carriers transmitted on the line are allotted respectively to each specific section of transmission line. These low-frequency carriers travel with a low loss along the transmission line and they are selected and converted by their respective frequency selection and converter device to a common high-frequency carrier signal for leaky transmission to a mobile station on the corresponding track section.