Abstract: A photosensor comprises a cathode portion (111) sensitive to radiation and/or particles, an anode portion (114) receiving electrons, an evacuated channel (112, 113, 200) having the cathode portion attached to its one end portion in a vacuum-tight manner and the anode portion attached to its other end portion in a vacuum-tight manner, a conductive or semiconductive layer (107) at least partially covering the inner surface of the evacuated channel, wherein the channel is formed of a tubular member (106). A method of manufacturing a channel electron multiplier comprises the steps of forming a tubular member and a conductive or semiconductive layer at least on parts of its inner surface, forming an anode portion and sealing it to the tubular member, evacuating the tubular member, forming a cathode portion sensitive to radiation and/or particles, and sealing the cathode portion to the evacuated tubular member. The detector may at least partially be packed into a casting compound.

Abstract: An active regulator that reduces the noise occurring on an image intensif tube particularly suited for use in night vision system is disclosed. The active regulator reduces the noise thereof and increases the sensitivity of the night vision system.

Abstract: A method for providing user adjustable variable gain for a night vision device which utilizes an image intensifier tube, wherein the image intensifier tube has a given life expectancy, the image intensifier tube is subjected to factory calibration for providing an optimum output during operation, wherein the calibration undesirably differs from tube to tube and is adjustable by variable control means coupled to the tube, whereby when one tube is substituted for another the difference in calibration causes non-optimum performance, the method including the steps of: determining minimum and maximum gain limits associated with the optimum output of the night vision device; factory calibrating gain limiting means according to the determined minimum and maximum gain limits, wherein the gain limiting means are associated with the image intensifier tube and for limiting the variable control means; and, tethering the gain limiting means to the image intensifier tube.

Abstract: A corona detector for detecting a corona associated with a remote object. In one embodiment, the corona detector employs an optical filter having at least one passband centered at a wavelength corresponding with one of the molecular nitrogen emission spectrum second positive emission lines in the visible spectrum for filtering light from the remote object. A lens operatively coupled to the optical filter forms an image of the remote object, the lens having high transmissivity in the visible spectrum.

Abstract: A monlithic housing assembly for an electronic device for providing electromagnetic interference (EMI) protection and positive and negative contact areas. The housing includes a hollow substantially cylindrical tube of uniform diameter for receiving the electronic device. The tube includes a first cylindrical outer surface comprising a first conductively plated portion defining a negative contact area and a second machined portion defining a positive contact area. The tube further includes a plurality of slot holes in the second machined portion which extend into the first conductively plated portion for receiving capacitive elements to provide EMI protection for the electronic device. First and second bore holes are located in respective first conductively plated portion and positive contact area for receiving corresponding negative and positive voltage terminals from the electronic device. A method for making is also disclosed.

Abstract: A fast power supply for an image intensifier tube used in night vision devices. The tube includes a microchannel amplification wafer placed between a photocathode and an output screen. The supply of the tube delivers a reference voltage to a first terminal of the wafer, a variable voltage to the second terminal of the wafer, a variable photocathode voltage and an output screen voltage. The illumination of the output screen is measured by its screen current. Beyond one screen value, and in order to maintain constant output illumination while avoiding dazzle, the voltage at the second terminal of the wafer is slaved to the changes in the screen current and is different from the photocathode voltages fixed. The circuit for controlling the circuit at the second terminal of the wafer includes a high voltage amplifier with transistors having small quiescent consumption and high control speed for decreasing or increasing the voltage as a function of the variations in the screen current.

Abstract: A night vision device includes an image intensifier tube having a photocathode responsive to light in the wavelength range extending from about 1 .mu.m to about 2 .mu.m. The photocathode releases photoelectrons in response to photons of light in this wavelength range. A photomultiplier tube includes such a photocathode to provide an image in response to light of such a wavelength. A method of making such a photocathode is set out.

Abstract: A night-viewing light amplifying viewer with a battery voltage driven light amplifier, operation of the focusing control and the electrical on/off-switch for the light amplifier being united to take place by the same operating device of suitably chosen dimensions.

Abstract: An integrated night vision device and laser range finder provides both night-time and day-time imaging by use of an image intensifier tube, as well as providing laser range finding operations both day and night. In a laser range finder mode of operation the device projects a pulse of laser light into a scene being viewed, and a power supply and laser range finder circuit of the device temporarily utilizes the image intensifier tube as a sensor to detect reflected laser light. During laser range finding, imaging is cut off for a very short time interval. Also, during imaging operations, the power supply and laser range finder circuit operates the image intensifier tube in a unique way in order to provide both improved automatic brightness control (ABC) and improved bright-source protection (BSP). The ABC and BSP functions are coordinated with the laser range finding function in order to prevent interference by the ABC or BSP functions with laser range finding operations.

Abstract: An X-ray image intensifier (1) includes an entrance screen (2) with a photocathode (3). A television camera (15) is optically coupled to the exit window (12) of the X-ray image intensifier. The X-ray image intensifier with the television camera derives a primary image signal form an X-ray image on the entrance screen. The X-ray image intensifier is provided with a radiation source (4), such as flashlights or LEDs, for irradiating the photocathode (3). Irradiation of the photocathode produces a light intensity distribution on the exit window wherefrom the television camera derives a control signal. Correction numbers are derived from the signal levels of the control signal. These correction numbers are employed for correcting the primary image signal.

Abstract: A night vision device with an image intensifier tube includes an improved power supply which operates the image intensifier tube of the device according to a variable duty cycle either at a design voltage level for the tube or at a voltage level simulating a dark-field. This duty cycle variation is effected as a function of the current flow in the image intensifier tube in order to provide automatic brightness control and bright source protection. An improved service life for the image intensifier tube is achieved. Also, a microchannel plate of the image intensifier tube need not carry an ion barrier film, resulting in an improved light amplification for the image intensifier tube.

Abstract: A night vision device (NVD) includes a control circuit having an acceleration-responsive switch. When the NVD is in a generally horizontal use position, the acceleration-responsive switch enables a circuit allowing voltage to be applied to an image intensifier tube of the night vision device, so that night vision is provided. On the other hand, when the device is flipped up to a stowed position allowing the user of the device unobstructed natural vision, the acceleration-responsive switch senses the changed orientation of the gravitational acceleration vector, and turns off the image intensifier tube as well as other light-emitting sources of the night vision device.

Abstract: A night vision device comprising a facemask housing assembly having a peripheral surface defined by a rear surface contoured to a user's face and an open front surface, the housing assembly operative for encasing a pair of optical assemblies operative for receiving light from a viewed object via a first folded optical path and via a second direct optical path, combining the light from the first and second paths, and directing the combined light to a user's eye for viewing the object; where each optical assembly detachably coupled to the housing assembly.

Abstract: A structure for detecting radiation, useful in an imaging camera for nuclear medicine, comprising a plurality of tubes, each of said tubes having (1) an electrically conductive wall structure defining a tube internal radius and a proximal and a distal end, (2) a pressure retaining and electrically insulative tube end closure means at each tube end, (3) a coaxial electrically conductive element located between said insulative tube end closure means; said tubes containing xenon at a pressure sufficient to provide for a photoelectron range there within of or less than that distance existing between the proximal and distal ends thereof and a maximum ionization collection distance of or less than the tube internal radius; said tubes positioned in a honeycomb-like array such that each proximal and distal tube end is in a common plane one with another, respectively.

Abstract: A cathode switch particularly suited for an image intensifier tube (IIT) is disclosed. The cathode switch provides cathode pulses to turn "on" and n "off" the IIT tube and does so with reduced power consumption and with reduced noise generated by associated high voltage switching.

Abstract: An improved intensity control system for an intensified imaging system allows continuous viewing through an intensified imaging system while protecting saturated areas from the negative effects of overexposure. A micromirror array (MMA) is used in conjunction with associated optics to control the intensity incident on the image intensifier. Control circuitry determines if pixel intensity is above or below the preset threshold level. If above, the corresponding elements of the MMA array will deflect the incident light in that specific area thereby eliminating saturation of the pixels. The rest of the image is maintained for continuous viewing. A continuous feedback loop monitors the intensity levels of pixels and actively controls the incident light using the MMA.

Abstract: A photocathode device for use in an image intensifier of a night vision device, the device having a faceplate fabricated from an optically transparent material and a photoemissive semiconductor wafer bonded to the faceplate. The photoemissive wafer includes a first contact disposed on a peripheral surface thereof for electrically contacting the wafer and an annular-shaped second contact disposed on the emission surface of the wafer for enabing a potential difference to be applied across the wafer to facilitate the emission of photogenerated carriers from the emission surface.

Abstract: A night vision device (10) includes an improved fine-resolution microchannel plate (22) having a multitude of microchannels (32). The microchannels (32) are defined in groups (32a, 32b), with each group having plural microchannels. Each group of the microchannels originates with a single fiber pre-form (50) used in a process of manufacturing the microchannel plate (22). A method of making such a microchannel plate (22) is also explained.

Abstract: An x-ray image intensifier includes a photoconductive x-ray detector having an electro-optic light modulator disposed on a photoconductive detector layer. The photoconductive x-ray detector absorbs x-rays passing through an object to be imaged to form an x-ray exposure of the object. An optical image of the x-ray exposure is generated when light passes through the photoconductive x-ray detector. An imager captures optical images of the x-ray exposures. A processor coupled to the imager digitizes and stores the optical images of the x-ray exposure captured by the imager at selected intervals.

Abstract: Streak camera whereof the pulse converter for converting a photon pulse for detecting into an electron stream comprises a gaseous medium. A streak camera for a photon pulse in the far-infrared region is provided with a laser source to bring particles in the medium into a Rydberg state, in a streak camera for an X-ray pulse the medium contains particles for bringing into an Auger state, and additional deflection plates are provided for separating a primary electron stream from a secondary electron stream.

Abstract: A microchannel plate and method of manufacturing same is provided. The microchannel plate includes a plate consisting of an anodized material and a plurality of channels which are formed during the anodization of the material and extend between the two sides of the plate. Electrodes are also disposed on each side of the plate for generating an electrical field within the channels. Preferably, the material is alumina and the channels are activated such that the channel walls are conductive and highly secondary emissive.

Abstract: An improved image intensifier tube has electrically operative components that include a photocathode having a photoemissive layer, a microchannel plate (MCP) having a conductive input surface and a conductive output surface, and a vacuum housing for retaining the photocathode, microchannel plate and a fiber optic inverter and screen within an evacuated environment. The fiber optic inverter has a circumferentially extending flange portion extending toward the housing to accommodate a sealing material which sealingly engages an inner surface of an output flange with the inverter flange portion to form an air impervious vacuum seal and where the output flange is supported by the fiber optic inverter flange portion. The improved intensifier includes a photocathode having a flat faceplate conductively engaging the photocathode along the entire surface of the faceplate.

Abstract: To provide an electron tube having good airtightness and being appropriate for mass production, indium affixed to the inner surface of a sealing metal support member is provided between a side tube and input faceplate. The input faceplate is pushed against the side tube. As a result, the indium is squeezed by a pressure receiving surface provided on the end face of the side tube. Since the pressure receiving surface is in a generally declining shape from the inside out, the force of the pressing surface causes the indium to flow outward toward the sealing metal support member. Therefore, the indium is firmly affixed to the pressure receiving surface, and the side tube and input faceplate can be reliably sealed by the indium.

Abstract: A method for forming a supported thin layer of non-evaporable getter (NEG) material and a getter device formed thereby are provided. A suspension comprised of non-evaporable getter (NEG) material particles in a dispersing medium is prepared. The NEG material particles in the suspension have a particle size not greater than about 150 .mu.m. The dispersing medium has an aqueous, alcoholic, or hydroalcoholic base and contains not more than about 1 wt % of organic compounds having a boiling temperature of at least about 250.degree. C. The ratio of the weight of the NEG material particles to the weight of the dispersing medium is between about 4:1 and about 1:1. A layer of the suspension is deposited on a carrier by a serigraphic technique. Next, the deposited layer is dried to evaporate volatile components of the dispersing medium and thereby form a dried deposit. Finally, the dried deposit is sintered under vacuum at a temperature between about 800.degree. C. and 1000.degree. C.

Abstract: In an image intensifier comprising an entrance faceplate, made of a material transparent to light, having a photoelectric surface, formed on a surface opposite to a light entrance surface, for photoelectrically converting incident light into an electron; and an optical fiber block, constituted by a plurality of optical fibers bundled together, having a phosphor face at an end face of each optical fiber on the light entrance side, for emitting light in response to the electron incident thereon; the photoelectric surface of the entrance faceplate and the phosphor face of the optical fiber block opposing each other, while a vacuum atmosphere being formed therebetween; the optical fiber block is provided with a pit in which an end face of a core portion of each optical fiber is recessed from an end face of a cladding portion thereof, the bottom of the pit is filled with a phosphor, the surface of this phosphor is provided with a metal back layer, the cladding portion projects from the surface of the phosphor towa

Abstract: A camera system for recording a transient radiation event consisting of direct (2) and scattered (4) radiation. The camera system comprises a first fluorescent screen (10) which produces a light image (11) of the direct radiation (2) and a television camera (18) which is positioned to receive that image (11) and which is provided with means for removing any spurious signals from the scattered radiation (4). A shutter means is placed between the screen (10) and the camera (18) which is arranged to open after the spurious signal has been removed to allow the camera to record the light image (11) retained on the screen (10).

Abstract: A streak tube sweeping method in which a synchronization scan sweeping signal of a fixed repetition frequency is applied to vertical deflection plates in a streak tube, causing an electron beam, generated when a light to be measured is introduced to a photocathode in the streak tube, to sweep at the fixed repetition frequency across a phosphor screen in a first direction. At predetermined intervals that are multiples of the synchronization scan sweeping signal period, a horizontal blanking signal is applied to horizontal deflection plates in the streak tube, causing the electron beam to sweep a streak once every pulse across an output effective area of the phosphor screen. Hence, information of emitted light can be accurately measured even if the life of the light to be measured is longer than the period of the synchronization scan sweeping signal (or the period of the light pulse output from a laser light source, which is the source of the sweeping signal).

Abstract: The disclosure relates to radiological image intensifier tubes comprising a vacuum electron tube and a luminescent observation screen comprising means to improve the contrast of the image. These means consist of a layer of aluminium with a thickness of at least 1 micrometer, partially absorbent for the incident electrons, placed in the path of the electrons generated by the tube and in the vicinity of the layer of luminophores. The deposited layer has the effect of reducing, firstly, the quantity of electrons re-emitted from the observation screen to the tube and, secondly, the proportion of these electrons that return to strike the layer of luminophores. Application to radiological type image intensifier tubes.

Abstract: A multi-function day/night observation, ranging, and sighting device with active acquisition of optical targets includes a single objective lens and a single eyepiece lens and provides an image of a scene. The single objective lens leads to a visible-light first optical path and to an invisible-light second optical path. The invisible-light second optical path includes an image intensifier tube providing a visible image. The first and second optical paths converge with visible images provided by each pathway being overlaid at a reticule plane. A single light path leads from the reticule plane to the eyepiece lens. A laser provides pulses of laser light projected into the scene via the single objective lens, and the image intensifier tube is used as a detector for a portion of the laser light pulses reflected from an object in the scene in order to provide both a laser range finding function and an active optical target acquisition mode.

Abstract: A night vision device includes an image intensifier tube, which includes a photocathode responsive both to white light and to infrared light to release photoelectrons. The photocathode is particularly sensitive to infrared light at the 980 nm wavelength, and has desirable spectral response characteristics.

Abstract: A sweep generator circuit generates a primary pulsed voltage and a secondary voltage which are applied to the deflection plates of a streak camera. A primary pulsed voltage generator includes at least one light operated switch for producing deflection of an electron beam in one direction. A secondary voltage generator means generates the secondary voltage which causes deflection of the electron beam in an opposite direction. Variations in the incident light intensity create substantially identical fluctuations in the deflection of the electron beam produced by the primary pulsed voltage and the secondary voltage. Additionally, any variations with respect to time in the deflection of the electron beam produced by the secondary voltage are small in comparison with variations in the deflection of the electron beam produced by the primary pulsed voltage. The sweep generator circuit has an operating point that is stable with respect to variations in the light intensity.

Abstract: A night vision device includes an improved power supply which operates the image intensifier tube of the device according to a variable duty cycle either at a design voltage level for the tube or at a voltage level simulating a dark-field. This duty cycle variation is effected as a function of the current flow in the image intensifier tube in order to provide automatic brightness control and bright source protection.

Abstract: A night vision device which applies a time-varying voltage to the photocathode of the device during periods of high average light intensity from a scene being viewed. The purpose of applying this time-varying voltage during periods of high average light intensity is to reduce the average current through the photocathode, thus increasing reliability for the night vision device while preserving image resolution.

Abstract: A monocular night vision device comprising an objective lens assembly for receiving low intensity light; an image intensifier assembly comprising a variable gain image intensifier tube having an adjustable potentiometer mounted external to the tube for converting the low intensity light into a visible output image; a single eyepiece lens assembly for viewing the output image from the image intensifier assembly; and a non-metallic housing for receiving the objective lens assembly, image intensifier assembly, and eyepiece lens assembly, wherein the housing aligns the objective lens assembly with the image intensifier assembly and the eyepiece lens assembly along an optical axis.

Abstract: An assembly is provided for detection of radiation directed through an object. A phosphor converter disposed to receive the radiation pattern generates visible light representative of the radiation pattern. A plurality of light sensors are disposed to define a sensor array for receiving the visible light and generating a pixel signal pattern representative of the radiation pattern. A plurality of reflectors are disposed at locations for reflecting a portion of the visible light radiating in a direction to avoid being received in the plurality of light sensors. The light is reflected back into the phosphor converter where a diffuse reflection of the reflected light redirects the light back towards the sensors.

Abstract: The pair of vertical deflection electrode plates 13 in the double sweeping streak camera are supplied with a voltage of a sawtooth wave in synchronization with the input optical beam pulses. The other pair of horizontal deflection electrode plates 14 are supplied with a voltage of a stepped wave in synchronization with the sawtooth wave. The deflection electrode plates 13 and 14 sweep successively-incident photoelectrons. The photoelectrons are then detected at the phosphor screen 16. The phosphor screen 16 is therefore recorded with temporal changes in the spatial pattern of the optical beam pulse as an image of regularly-arranged optical beam patterns. The image analyzing device can easily analyze the image.

Abstract: This invention relates to an electron tube which stabilizes the orbits of electrons accelerated and focused by an electron lens and has a structure for effectively suppressing noise generated due to discharge. This electron tube has, at two ends of an insulating container, a cathode electrode and an anode electrode which constitute the electron lens. Particularly, in the electron tube, one end of the cathode electrode and a photocathode are supported by a conductive member arranged at one end of the insulating container, and the cathode electrode is electrically connected to the photocathode. The cathode electrode partially extends to a stem along the inner wall of the insulating container and is tapered toward the stem so that the distal end portion of the cathode electrode is separated from the inner wall of the insulating container.

Abstract: A method and apparatus to correct and eliminate optical anomalies and geometrical distortions in an intensified imaging system, specifically a night vision system. An image is received from the original objective lens assembly of an unintensified imaging system which, presumably, has been designed to produce images sized in accordance with the image sensor size of its host camera or camcorder. The format matching lens assembly receives the image from the original objective lens system and magnifies it so that it is output onto the entire circular active area of a mechanically inserted image intensifier. Having received an image across its entire circular active area, the image intensifier is able to amplify or intensify the image using the received light without creating any optical distortions. Once intensified without distortion, the image must be still further modified to fit its original format size.

Abstract: A multi-function day/night observation, ranging, and sighting device includes a single objective lens and a single eyepiece lens and provides an image of a scene. The single objective lens leads to a visible-light first optical path and to an invisible-light second optical path. The invisible-light second optical path includes an image intensifier tube providing a visible image. The first-and second optical paths converge with visible images provided by each pathway being overlaid at a reticule plane. A single light path leads from the reticule plane to the eyepiece lens. A laser provides a pulse of laser light projected into the scene via the single objective lens, and the image intensifier tube is used as a detector for a portion of the laser light pulse reflected from an object in the scene in order to provide a laser range finding function.

Abstract: The invention comprises a mounting assembly for an image intensifier tube in an optical sight. In accordance with one embodiment of the invention, a mounting assembly (152) may include a housing (154), a retainer (158) and a locking device (177). The housing (154) may be mounted to an optical bench (60). The retainer (158) may engage an image intensifier tube (150) and be coupled to the housing (154). The image intensifier tube (150) may be rotatable relative to the optical bench (60). The locking device (177) may selectively secure the image intensifier tube (150) relative to the optical bench (60).

Abstract: An optical correlator for correlating incident optical signals is described. The correlator comprises a transmission line in close juxtaposition to a photoconductor. The photoconductor may be positioned within the transmission line. The transmission line and the photoconductor may be monolithically integrated on a substrate. The optical correlator has an electrical non-linear response to the incident optical signals that results from a voltage divider formed from the combination of the transmission line and the photoconductor. The electrical non-linear response is proportional to a second-order intensity autocorrelation function g.sup.(2) (.tau.). The response time of the electrical nonlinear response is less than the width of the narrowest pulse of the optical signals and may be less than twenty picoseconds.

Abstract: A lightweight night vision device that can be used by itself or can be selectively attached to either the objective lens assembly or ocular lens assembly of an existing optical device. The night vision device includes an image intensifier tube for amplifying low intensity light to produce a visible image. The image produced by the image intensifier tube is inverted. A prism assembly is positioned proximate to the image intensifier tube to reinvert the image in a space and cost efficient manner. The image intensifier tube, the power supply for the image intensifier tube and the reinverting prism are all contained within a house just large enough to accommodate these components. The housing has an objective port and an ocular port. Both ports are adapted to be joined to other optical components. As a result, a large variety of optical devices can be attached to either the object port or ocular port of the night vision device, thereby providing night vision capabilities to the optical device.

Abstract: A corona detector for detecting a corona associated with a remote object. In one embodiment, the corona detector employs an optical filter having at least one passband centered at a wavelength corresponding with one of the molecular nitrogen emission spectrum second positive emission lines for filtering light from the remote object. A lens operatively coupled to the optical filter forms an image of the remote object, the lens having high transmissivity in the ultraviolet spectrum.

Abstract: A photomultiplier includes a cathode supporting member, arranged in a tube and comprised of a conductive material, for holding a photocathode, and a holding mechanism, comprised of a heat conductive material, for biasing the cathode holding member to hold it. The holding mechanism is thermally connected to a cooler.

Abstract: A night vision device having a power supply which delivers a high voltage level to its microchannel plate (MCP) through a variable resistance device. The voltage to the MCP is monitored and used to control the resistance to the variable resistance device such that the voltage on the MCP remains substantially at an established level, notwithstanding variations in the current being drawn by the MCP.

Abstract: A night vision device includes an improved image intensifier tube providing an image with reduced dark spots caused by microscopic particulate contamination in the tube. A method of processing image intensifier tubes to reduce dark spots caused by such microscopic particulate contamination within the tubes is disclosed.

Abstract: The present invention relates to an electron tube includes, at least, a cathode electrode and a face plate having a photocathode which are arranged at one end of a body, and a stem arranged at the other end of the body for defining the position of an electron entrance surface where the electron emitted from the photocathode reaches. The object of the present invention is to provide an electron tube which can reduce its size and has a structure for improving the workability in its assembling process. In particular, the electron tube in accordance with the present invention comprises a bonding ring, provided between the face plate and the cathode electrode, for bonding the face plate and the cathode electrode together. The bonding ring is made of a metal material selected from the group consisting of In, Au, Pb, alloys containing In, and alloys containing Pb.

Abstract: In the photomultiplier tube 1, the focusing electrode plate 17 has the focusing portion 20 for focusing incident electrons and the frame 21 surrounding the focusing portion 20. The focusing portion 20 has a plurality of slit openings 18. The dynode unit 10 is constructed from a plurality of dynode plates 11 laminated one on another. Each dynode plate 11 has a plurality of electron through-holes 13 located in confrontation with the plurality of slit openings 18. A plurality of anodes 9 are provided for receiving electrons emitted from the respective through-holes 13 of the dynode unit 10. The frame 21 has dummy openings 22 at positions located in confrontation with edges 15 of the first stage dynode plate 11a in the dynode unit 10.

Abstract: This invention relates to an electron tube having a structure for enabling a stable operation for a long time. In the electron tube, at least a confining mechanism is arranged between a photocathode and the electron incident surface of a semiconductor device, which are arranged to oppose each other through a container. Particularly, the area of the opening of the confining mechanism is smaller than that of the electron incident surface, thereby confining the orbits of photoelectrons from the photocathode. This structure avoids bombardment of electrons arriving at portions other than the electron incident surface of the semiconductor device and prevents the semiconductor device from being unnecessarily charged.

Abstract: MUX and DEMUX circuits using a photo gate transistor having a pair of thin film electrodes respectively serving as emission and collector electrodes. When photons with at least critical energy are irradiated onto the emission electrode, electrons are emitted from the emission electrode, so that the associated photo gate transistor can carry out a gating operation. The MUX circuit divides a plurality of electrical signals in a time division manner so that the transmission of those signals can be carried out through a single transmission line. The DEMUX circuit recovers an original signal from signals transmitted in a time division manner via a single transmission line. Input signals are received to emission electrodes while being limited in voltage level by input resistor pairs. An optical source irradiates photons to an emission electrode in sync with the application of an input signal. By the irradiation of photons, the emission electrode emits electrons which are transmitted to a collector electrode.