Abstract: A muitilayer microelectronic photomultiplier device is fabricated by disce procedures to provide a photocathodeanode and dynode chain arrangement which is analogous in operation to conventional photomultiplier tubes. This multilayer microelectronic photomultiplier device provides for low level photon detection and realizes the advantages of high reliability, small size and fast response, plus lower cost, weight and power consumption compared to conventional photomultiplier tubes. In addition, the fabrication on an SOI substrate permits integration of logic and control circuitry with detectors. The insulating substrate also permits the integration of an on-chip high voltage supply and may easily be extended to a plurality of detectors with high packing densities due to the inherently stacked geometry offering improved performance and design flexibility.

Abstract: Two photomultipliers (14,16) are arranged one on either side of a CRT (10) primary optical axis adjacent the imaging lens. High frequency components of the detected CRT brightness signal from the two photomultipliers are applied to the "gate" 32. When the signals are equal, one or other of the signals will be selected by the "gate". When the signals are unequal, the lower one will be rejected. Thus signals caused by faceplate (22) dirt are eliminated, since they appear displaced in time from the photomultipliers, due to the spacing of the dirt from the scanning beam and the spacing of the photomultipliers. Phosphor grain and blemish signals occur at the outputs of the photomultipliers simultaneously and are allowed through the "gate" to provide correction and attenuation of these unwanted signals.

Abstract: The present invention provides a method of forming a semiconductor device mprising the steps of:forming a glass block of an acid inert glass having acid etchable glass rods extending therethrough, the acid etchable glass rods having an average diameter of less than 1 micron;partially etching one end of the acid etchable rods surface of the glass block to form cavities in the glass block on one surface thereof having an average diameter of less than 1 micron;depositing material(s) in the cavities to form a semiconductor device.The present invention also provides a method for forming a semiconductor device in which the acid etchable glass rods are completely etched and the deposition material(s) is deposited to fill the nanochannels formed by the etching.The present invention also provides semiconductor devices made by these methods.

Abstract: A microelectronic photomultiplier device is fabricated by discrete proceds to provide a photocathode-anode and dynode chain arrangement which is analogous in operation to conventional photomultiplier tubes. This microelectronic photomultiplier device provides for low level photon detection and realizes the advantages of high reliability, small size and fast response, plus lower cost, weight and power consumption compared to conventional photomultiplier tubes. In addition, the fabrication on an SOI substrate permits integration of logic and control circuitry with detectors. The insulating substrate also permits the integration of an on-chip high voltage supply and may easily be extended to a plurality of detectors offering improved performance and design flexibility.

Abstract: The scintillation camera includes a plurality of individually pulsible light emitting devices associated with a number of the photomultiplier tubes. By pulsing the light emitting device, certain ones of the photomultiplier tubes of the camera receive substantial amounts of light. Values from the certain photomultiplier tubes are compared to one another for carrying out an effective gain adjustment of at least one of the certain tubes. The gain calibration is independent of the amount of light emitted from the light emitting devices. There is also provided a method of adjusting the effective gain of the camera by using the readings resulting from a gamma ray induced scintillation instead of the pulsible light emitting devices.

Abstract: There is disclosed a phototube comprising a closed container having a light permeable face plate the outside surface of which is a light incident surface, a photocathode so provided in the closed container that at least a part of a photo-electric surface is inclined to the light incident surface, and an anode so provided in the closed container that an electron capturing surface is opposed to the photo-electric surface in parallelism therewith.

Abstract: A surface is probed with a pulsed electron beam and secondary electrons are detected to produce a detector signal. First portions of the detector signal are substantially dependent on the voltage of the surface being probed, while second portions of the detector signal are substantially independent of the voltage of the surface being probed. In general, the first and second portions of the detector signal include unwanted noise caused by low-level sampling due to beam leakage and/or by scintillator afterglow in the secondary-electron detector. The detector signal is sampled during the first signal portions and is sampled during the second signal portions. The sampled first signal portions are combined with the complement of the sampled second signal portions to produce a measured voltage signal representing voltage of the conductor. In a preferred sampling scheme, alternate electron-beam sampling pulses are held-off.

Abstract: An optically powered photomultiplier tube is provided, comprising a vacuum chamber having a window for incident optical radiation which is to be detected; a photocathode to receive the optical radiation; an electron multiplier system within the chamber to amplify the electron current from the photocathode; an anode to receive the amplified electron current; a high voltage photocell array positioned within the chamber for generating high voltage electrical power that is provided to the electron multiplier system; a system for delivering optical power to the photocell array; a first electrical contact penetrating the container in a vacuum tight manner and operably coupled to the anode; and a second electrical contact penetrating the container in a vacuum tight manner and operably coupled to the photocell array.

Abstract: A conductively cooled microchannel plate is disclosed. Cooling is achieved by placing an active face of the MCP in thermal contact with a thermally conductive substrate for dissipating joule heating.

Abstract: A gain stabilization system for photomultiplier tubes using a pulsed light source, preferably a light emitting diode (LED), the signal of which is detected at the first dynode and at the anode. The gain of the photomultiplier tube is stabilized by keeping the ratio between the two signals constant.

Abstract: A photomultiplier tube comprises a photocathode (10) deposited on an input window (20) sealed to one end of a sleeve (30), an input electrode (40), and an electron multiplier (50) with stacked dynodes. The input electrode (40) is constituted by a truncated cone conductor on the inside of which the electron multiplier (50) with stacked dynodes is deposited. A generator (61,62) of a material forming the photocathode (10) is advantageously placed in the space (70) situated between the input electrode (40) and the sleeve (30).

Abstract: A photomultiplier tube in which the a semiconductor photodiode serves as the anode and receives the electrons from the photocathode. The particular geometry for the focusing electrodes in the tube involves a two part structure with one part, the anode focus electrode, in close proximity to the semiconductor photodiode. The second part of the focus structure is a grid focus electrode with two different diameters, located approximately midway between the photodiode and the photocathode and operating on a low voltage. Together the electrodes create a focusing electric field so that the electrons from the large area photocathode are efficiently delivered to the small area of the semiconductor photodiode. The mounting of the photodiode is also designed to act as a termination to furnish superior timing characteristics.

Abstract: A photomultiplier tube has a multi-anode array consisting of a first group of anodes arranged in the Y-direction and a second group of anodes arranged in the X-direction in the form of a plurality of rows. Each of the anodes of the first group for detecting a receiving position of photoelectrons in the Y-direction contains the associated anodes of the second group for detecting the receiving position of photoelectrons in the X-direction so as to form an empty space therebetween.

Abstract: A stripline is composed of a microchannel plate, and a gold transmission path and grounded electrode formed on both surfaces of the microchannel plate. X-ray images projected onto the transmission path is gated by a pulse voltage applied to and propagating through the stripline. The stripline has such a characteristic impedance profile as decreases toward its output end. This impedance profile compensates for a voltage drop due to the transmission loss which would otherwise appear.

Abstract: An advantageous device and method enables a photomultiplier to be gated on and off at electronic rates. A single multi-winding pulse transformer is employed to enable the triggering of the photomultiplier tube.

Abstract: A low light sensing and amplifying device uses an automatically adjustable electro-optic shutter that quantitatively attenuates the amount of monitored electromagnetic energy impinging on a light processor in proportional relation to the electromagnetic energy's intensity. An output signal from the light processor controls the output of a power supply which provides an output supply signal to the electro-optic shutter.

Abstract: A modular channel electron multiplier mounting arrangement for an analytical instrument, which reduces the labor required for assembly and, at the same time, results in a more rigid structure with lower susceptibility to microphonic noise has been developed. A circuit board and an attached end support has slotted portions for engaging support studs on the instrument. A channel electron multiplier is mounted on the circuit board by means of supporting hardware. Printed circuit wiring on the circuit board carries signal and high voltage to receptacles on the circuit board which when installed in the instrument are aligned for securely engaging leads in the instrument. The end support and the receptacles rigidly support the assembly in the instrument such that microphonics noise is significantly reduced.

Abstract: The present invention is directed to method and means for converting an energetic radiation image into an accelerated electron image, impacting the accelerated electron image onto an anode target to create both a charge image an a visible light image, producing signals representative of at least one of the two spatial coordinates of the electrons on the target and transmitting the visible light image for viewing.

Abstract: A measurement of standard light is performed during radiation measurement for gain correction and offset correction of radiation measurement apparatus. The standard light emitted by a LED falls on a PMT. An output signal of a preamplifier corresponding to the PMT is entered into a system controller after being subjected to predetermined analog signal processing. The system controller calculates a gain correction value and an offset correction value on the basis of initial correction values and an output value of the preamplifier, whereby gain control and offset control can be performed stably even in radiation measurement.

Abstract: A structure for supporting a funnel portion of a secondary electron multiplying tube in a secondary electron multiplier. In the supporting structure for the funnel portion, a support member has a circular contact element for supporting an end face of a mouth of the funnel, and nails formed along the outer periphery of the circular contact element so as to grasp the mouth end portion of the funnel from the outside thereof. A press member is welded to the support member into which the funnel portion is inserted. The posture and position of the funnel portion are correctly determined in relation to an opening of a Farady cup, by fixing the support member to a casing of the secondary electron multiplier.

Abstract: A photomultiplier tube having an electron multiplier comprising a dynode with an attachment lip (10) which is introduced into a slot (20) which is formed in a supporting board (30), the said slot (20) comprising, on the one hand, two outer supporting points (21a, 21b) against which the said attachment lip (10) bears with a first surface (11), and which supporting points have rounded end portions (22a, 22b) and, in addition, at least one central supporting point (23) on which the said attachment lip (10) abuts via a second face (12), which slot (20) comprises holes (24a, 24b, 25) which are located opposite the said outer supporting points (21a, 21b) and the central supporting point (23).

Abstract: A radiation image read-out apparatus comprises a system for scanning a stimulable phosphor sheet, on which a radiation image has been stored, with stimulating rays in a main scanning direction, i.e. along a main scanning line, and a system for moving the stimulable phosphor sheet with respect to the stimulating rays in a direction approximately normal to the main scanning direction. An elongated photomultiplier having a light receiving face, which extends along the main scanning line on the stimulable phosphor sheet, is provided for detecting light emitted by the stimulable phosphor sheet during scanning. The elongated photomultiplier has a cylindrical main body, a photocathode provided on an inner surface of the main body, and a light guide member which extends along the light receiving face and guides the emitted light toward the photocathode.

Abstract: A conductively cooled microchannel plate is disclosed. Cooling is achieved by placing an active face of the MCP in thermal contact with a thermally conductive substrate for dissipating joule heating.

Abstract: A photomultiplier tube comprising a photocathode, a plurality of mesh dynodes arranged parallel to the photocathode, an anode that is disposed in a face-to-face relationship with the photocathode in such a manner that the mesh dynodes are interposed between the anode and the photocathode, the anode being divided into segments larger than the openings of each dynode, and at least one layer of focusing electrode for focusing an electron beam by the lens action which is disposed between the photocathode and the anode.

Abstract: A microchannel electron multiplier is formed by placing into a glass tube a plurality of bundles optical fibers, each having an etchable glass core and a glass cladding which is non-etchable when subjected to the conditions used for etching the core material. The fiber bundles located around the inside edge of the glass tube are replaced by support fibers having both a core and a cladding of a material which is non-etchable under the above-described conditions. The assembly of the tube, bundles and support fibers is heated to fuse the tube, bundles and support fibers together. The etchable core material is then removed and the assembly sliced into wafers. The inner surface of each of the claddings which bound the channel formed after removal of the core material is rendered electron emissive by reduction of the lead oxide by hydrogen gas. Metal films are deposited onto the opposed surfaces of each of the wafers to form contacts.

Abstract: A long photomultiplier comprises a cylindrical main body having a light receiving face which extends in the longitudinal direction of the main body, a photocathode provided inside of the main body so that the photocathode extends along the light receiving face and emanates photoelectrons when exposed to light, and dynodes provided inside of the main body for multiplying the emanated photoelectrons. A reflection plate is provided facing and extending along the light receiving face, and the photocathode is positioned between the light receiving face and the reflection plate. The reflection plate is positioned for reflecting light, which has passed through the photocathode, toward the photocathode.

Abstract: An image read-out apparatus includes a main scanning device for scanning a sheet carrying an image recorded thereon with a light beam in a main scanning direction and obtaining light carrying the image information from the sheet, a sub-scanning device for moving the sheet with respect to the light beam in a sub-scanning direction approximately normal to the main scanning direction, and a light detector for detecting the light obtained from the sheet. The light detector comprises a long photomultipler having a light receiving face extending along the main scanning line and positioned close to the sheet.

Abstract: In an apparatus for automatically stabilizing the amplification degrees of photomultipliers (PMT's) in a detector having a scintillator and a plurality of PMT's, the PMT's (3) are classified into groups (A, B, C and D) and arranged such that the PMT's of the same group are not disposed adjacent to each other. Outputs taken from the PMT's (3) are classified according to the groups and summed in adders (6) allotted to the respective groups. A sum signal taken from a group which includes a PMT disposed closest to a scintillation is analyzed by a pulse height analyzer (14). The outputs from the pulse height analyzer are collected in a counter memory (15) as statistical data on a change in the amplification degrees of PMT's. Data on the high voltage to be applied to each PMT (3) is recorded beforehand in a register (17) and this data is corrected by a data processing circuit (16) in accordance with the statistical data.

Abstract: A photomultiplier tube which may be used in time resolving a luminiscence profile emitted from a sample with picosecond resolution using short (picosecond) electrical pulses as a probe and in time resolving an electrical pulse profile produced by fast electronic or optoelectronic devices with femtosecond resolution, using short (femtosecond) laser pulses as the probe is disclosed.

Abstract: A photomultiplier for converting an incident weak light into multiplied electrons to thereby output an electrical signal corresponding to the intensity of the incidence light. The photomultiplier comprises a photocathode for emitting primary electrons; plural dynodes for emitting secondary electrons in response to incident of the primary electrons and multiplying first secondary electrons passing between the dynodes; and shield means for preventing second secondary electrons emitted from a first dynode of the dynodes toward the photocathode from returning to the dynodes, thereby to reduce the generation of a residual pulse currents caused by the second secondary electrons and to accurately detect a main pulse current caused by the first secondary electrons.

Abstract: A technique for controlling the gain of a photomultiplier tube (PMT) 20. A voltage divider (resistors 45-49 in FIG. 1 and zener diodes 60-65 in FIG. 3) is used to control the potentials on dynodes 5, 7, and 9 of PMT 20. Transistor switches 53 and 58 provide the control of the voltage divider in FIG. 1 and photodiodes 66, 67 and 70 provide the control in FIG. 3. The gain control of PMT 20 is in the range from 100% to less than 0.001% (100,000 to 1).

Abstract: Improved gain control in a photomultiplier tube having a plurality of dynode stages is achieved through manual or automatic change of the bias voltage on at least one of the several dynodes between the anode and cathode of the tube. By such means, maximum tube gain change is obtained with a minimum of bias voltage swing.

Abstract: A circuit for automatically removing battery power from a night vision goggle (10) upon its detachment from a headgear (12) or when subjected to excessive light. A magnet (34) on the headgear (12) is magnetically coupled to a magnetic reed switch (36) fixed to the goggle (10). On detachment of the goggle (10) from the headgear (12), the reed switch (36) switches battery current to a goggle location monitor (75) for drilling on/off control logic (79) to remove power from an image intensifier tube (40). A high intensity light monitor (80) senses when the ambient light exceeds a predefined intensity, for a predetermined period of time, and also drives the control logic (79) to open a switch (86) in series with the battery (38) and the image intensifier tube (40). A low voltage monitor (82) provides a visual indication (84) of reduced battery voltages.

Abstract: Method for luminosity measuring advantageously in TLD evaluation equipment in the course of which a photomultiplier current is made proportional with light intensity and the current is measured; and sensitivity control of photomultiplier is conducted by varying its supply voltage if the current is above a given level. The change is stored. The measurement is conducted in analog or digital form. Circuit arrangement to implement the procedure has a photomultiplier tube (11), high voltage power supply and level sensor, the input of the photomultiplier tube being connected to the output of the high voltage power supply, the output of the tube being connected to the input of the level sensor. A control unit (14) is provided, whose input is connected to the output of the level sensor (12), and its output is connected to the input of the high voltage power supply.

Abstract: A canal structure of an electron multiplier, especially for an X-ray image intensifier, comprises several perforated metal dynodes which emit secondary electrodes and between each of which a plate-shaped separating element of electrically insulating material with an at least largely regular hole pattern is arranged. This canal structure has a relatively simple design, in which undesirable charging up at the separating elements is prevented to a large degree. The metal dynodes are realized as impingement dynodes of thin perforated foils or screens or nets or grids, where at least four holes each fall on the area occupied by a canal-like hole of the plate-shaped separating element. The plate-shaped separating elements have a comparatively greater thickness than the thickness of the perforated foils or screens and have on their upper and lower flat sides a layer of electrically highly conductive material and have at their hole walls a layer of an electric resistance material.

Abstract: A high speed light detection tube consists of a planar photoelectron source of transparent type, a photoelectron collection electrode arranged in parallel with the photoelectron source and an acceleration electrode of transmission type arranged in parallel with the photoelectron source in a space between the photoelectron source and the photoelectron collection electrode. The potential distribution has been set so that the photoelectrons passing through the acceleration electrode can be incident on the photoelectron collection electrode at a constant speed or near value.

Abstract: A two-dimensional energy position detector includes an array of wedge-shaped anodes arranged in an alternating sequence. Each of the anodes is connected to a multiplexer which is controlled by a sequencer to place the signals from the anodes in a predetermined sequence onto a multiplex output line. A data processor may then analyze the signal on the multiplex output line to determine the position of energy incident on the anodes.

Abstract: A photomultiplier used in liquid scintillation counting has an envelope, a base, an anode, a curved dynode structure and a photocathode. A specimen is inserted in a measuring area of the envelope for liquid scintillation counting. The photocathode has a concave surface, so that the specimen is encircled by the photocathode as completely as possible. The photocathode is positioned at a concave window of the envelope, so that a maximum number of photons directly impinge on the photocathode.

Abstract: An electron multiplier includes a micro-channel plate (12) having secondary electron emission. The channel plate is fitted in an annular metal frame (16, 17) which is in direct electrical contact with one (13) of the metallizations (13, 14) on the faces of the channel plate. The frame constitutes the means to apply an electric potential to one of the faces of the channel plate. The means to apply an electric potential to the other face of the channel plate are constituted by metallic contact studs (25) fixed in an insulated manner on the metallic frame and connected to the metallization (14) of the other face by means of conductor wires (30). The multiplier is incorporated in a detector device, the frame being soldered to the body (45) of the device by means of rods (48) traversing the body and soldered thereto.

Abstract: A digital gain controlled current to voltage amplifier having particular utility for interfacing with and forming part of a spectrophotometer system with a photomultiplier tube being responsive to light for producing an analog current proportional to the intensity thereof. The digital gain controlled current to voltage amplifier incorporates a current switched multiplying digital-to-analog converter inside its feedback loop. In this manner, the feedback loop impedance may be maintained constant as its gain is varied under control of a software programmed microcomputer.

Abstract: A photomultiplier control circuit includes a circuit for receiving an output signal of a photomultiplier, which detects a light to be measured and converts the detected light to an electric signal in order to generate an output depending on a level of the light to be measured. A light source is used for applying a compensating light to the photomultiplier and a circuit is provided for detecting an average anode current of the photomultiplier. A comparison circuit compares outputs of both circuits and generates the resulting difference output. A control circuit controls the intensity of a light emitted from the light source based on the difference output. The circuit is capable of stabilizing gain fluctuations of a photomultiplier when the incident light is input thereto in the form of a direct current, and also capable of maintaining the accuracy of a photomultiplier when it is employed in measuring tools, etc.

Abstract: An imaging dynodes arrangement for an electron multiplier, which comprises a first and a second imaging dynodes having dynode cones with a cone tip and a cone base, said dynode cones being connected with each other such that they form free cavities therebetween. Furthermore, there are needle-shaped extraction points arranged at the cone tips of at least the dynode cones of the second imaging dynode. The second imaging dynode is mounted beneath the first imaging dynode in a staggered position such that the cone tips of the dynode cones of the second imaging dynode are seated beneath the cavities of the first imaging dynode, directing the needle-shaped extraction points closely to the cavities. In a preferred embodiment the needle-shaped extraction points protrude into the cavities.

Abstract: A dynodes arrangement for an electron multiplier. It comprises a first dynode having a first voltage input; a second dynode having a second voltage input; and a control grid positioned between the first and second dynodes and having a control voltage input separate from the first and second voltage inputs of the first and second dynodes.

Abstract: Radioactive specimens are placed in the well (12) of a plastic scintillator body (11), and the light flashes from the scintillator body (11) are picked up by a photomultiplier tube (13). The anode (44) and dynodes (43) of the photomultiplier tube (13) are electrically isolated and a selected biasing voltage is provided across the cathode (42) and dynodes to operate the photomultiplier tube in its linear range at the activity level of the specimen. At high activity levels, the current flowing from the anode (44) is measured by an electrometer (21) to determine a value which is directly related to the activity of the specimen, whereas at lower activity levels where anode current is not accurately measurable, the pulses at the last dynode (50) are counted to determine the scintillation rate and thereby the activity level of the specimen.

Abstract: In an image intensifier night sight having a graticule illuminator, it is desirable that the brightness of the graticule should be maintained in proportion to the intensifier output image brightness so that the visibility of graticule and scene details are preserved. Such a sight comprises an image intensifier (2) having an image photocathode input (8) and an electron luminescent output image screen (12), a magnifier (3) for viewing the output image screen, a graticule injection system (5) for superposing a graticule (4) upon the output image screen, and a light source (14) for illuminating said graticule. In a power supply (15) for such a sight means (19) are provided for deriving a signal related to the brightness of the output image screen and for controlling the brightness of the light source in response to the signal to maintain the ratio between output screen and graticule brightnesses substantially constant.

Abstract: A photomultiplier tube which is insensitive to high magnetic fields comprises a photocathode deposited on a transparent window at the end of an insulating casing. The multiplier tube comprises a single amplifier stage comprising a dynode. The dynode is a metallic sheet with a circumference substantially surrounding the photocathode. A layer of a secondary emissive material is provided on the inner face of the dynode. An anode is formed of a metallic grid which is homeomorphous to the surface of the dynode. The anode is placed parallel to and at a short distance from the inside surface of the dynode.

Abstract: In an image scanning and read-out system wherein a sheet carrying an image recorded thereon is scanned with a light beam at an amplitude larger than the sheet width, and detecting the light from the sheet by use of a photomultiplier, the voltage applied to the photomultiplier is decreased when the output current obtained from the photomultiplier at the time the photomultiplier receives light from outside the sheet is larger than a predetermined reference level. The output current obtained when the scanning position of the light beam is at the outside of the sheet is compared with the reference level, or the period during which the output current is continuously larger than the reference level is measured to check whether it is longer than the time required for the light beam to scan the sheet width.

Abstract: A light detecting apparatus comprises an elongated plate-shaped light guide member having an end face at one long side as a light input face and an end face at the other long side as a light output face. N number of photomultipliers having elongated light receiving faces optically associated with N divisions of the light output face divided into N divisions in the length direction of the light output face of the light guide member are positioned for converting the light emitted from the divisions of the light output face into electric signals. The photomultipliers are connected to a correction circuit for electrically eliminating deterioration in sensitivity at least at adjacent photomultiplier side end portions of the photomultipliers.

Abstract: A gain adjuster circuit is disclosed for adjusting the gain of a plurality of photomultiplier tubes (PMT's) by digital circuitry. The circuit includes a plurality of PMT's, each having a specific internal resistance. A plurality of switches and resistances are connected in series with the PMT's. The digital circuitry is designed for adjusting the effective resistances thereof, to adjust thereby the voltage across each of the several PMT's. Preferably, the digital circuitry includes a demultiplexer coupled, via the switches and resistances, to the PMT's, a flip-flop coupled to the demultiplexer, and a presettable counter coupled to the flip-flop.

Abstract: A detector for the detection of, for example, Cerenkov radiation includes an entrance screen (5) which may cover more than half of an envelope (1); the majority of the envelope is preferably spherical. A photo-electron detecting exit screen (11) is proportioned and arranged inside the envelope (1) so that a small decay time and a high sensitivity are achieved. A scintillant exit screen (11), which is mounted on an indentation (15) in the envelope (1), can thus produce, in conjunction with a photomultiplier tube (17) mounted inside the indentation (15), a photoelectric intensification by a factor 100.