Photomultiplier Patents (Class 313/532)
  • Patent number: 7667400
    Abstract: Back-illuminated silicon photomultipliers having a substrate of a first conductivity type having front and back sides, a matrix of regions of a second conductivity type in the substrate, a matrix of regions of the first conductivity type under the matrix of regions of the second conductivity type and adjacent the back side of the substrate, with the bottom of the matrix of regions of the second conductivity type forming a p/n junction with the substrate or a matrix of regions of the second conductivity type, the matrix of regions of the first conductivity type having a higher conductivity than the substrate, a common anode formed by a uniform layer of the first conductivity type of higher conductivity than the substrate on the back side of the substrate. Preferably a plurality of trenches filed with an opaque material are provided in the back side of the substrate, the substrate preferably having a thickness of less than approximately 150 um.
    Type: Grant
    Filed: June 7, 2007
    Date of Patent: February 23, 2010
    Assignee: Array Optronix, Inc.
    Inventor: Alexander O. Goushcha
  • Patent number: 7667399
    Abstract: A large area hybrid photomultiplier tube that includes a photocathode for emitting photoelectrons in correspondence with incident light, a semiconductor device having an electron incident surface for receiving photoelectrons from the photocathode, and a cone shaped container. The container has a first opening and a second opening. The photocathode is disposed at the first opening, and the semiconductor device is disposed at the second opening.
    Type: Grant
    Filed: April 26, 2007
    Date of Patent: February 23, 2010
    Assignee: The United States of America as represented by the Secretary of the Navy
    Inventors: Vincent Michael Contarino, Pavlo Molchanov
  • Patent number: 7649163
    Abstract: An extension line of a tube axis of a photomultiplier tube is shifted from the center of gravity position of a front surface of a housing, which allows a space to be formed at an opposite side in the housing. A signal processing board is arranged in this space, and a high-voltage generating circuit board is fixed on the extension line of the tube axis, and thus the interior space of a housing can be effectively used. Since the signal processing board can be made adjacent to a tube wall of the photomultiplier tube, even when the length in a tube axis direction of the signal processing board is long, it becomes possible to house the same in the housing. Therefore, it becomes possible to achieve miniaturization.
    Type: Grant
    Filed: April 1, 2008
    Date of Patent: January 19, 2010
    Assignee: Hamamatsu Photonics K.K.
    Inventor: Takanori Nakaya
  • Patent number: 7602122
    Abstract: The present invention relates to a photomultiplier of a fine structure that realizes a high multiplier efficiency. The photomultiplier comprises an outer casing whose interior is maintained at vacuum, and, in the outer case, a photocathode that emits photoelectrons in response to incident light, an electron multiplier section that performs cascade multiplication of the photoelectrons emitted from the photocathode, and an anode for taking out secondary electrons, which are generated at the electron multiplier section, are arranged. In particular, groove portions for performing cascade multiplication of electrons from the photocathode are provided in the electron multiplier section, and on the respective surfaces of each pair of wall portions that define the groove portions are provided with one or more protrusions each having a secondary electron emitting surface formed on the surface thereof.
    Type: Grant
    Filed: February 16, 2005
    Date of Patent: October 13, 2009
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Akihiro Kageyama, Keisuke Inoue, Masuo Ito
  • Publication number: 20090242777
    Abstract: The present invention provides a photomultiplier tube interface device (PMT), comprising a PMT module and a circuit substrate. The PMT module comprises a plurality of pins formed at a front end. A plurality of contacts are disposed on a lateral side of the circuit substrate to be electrically connected to the plurality of pins while a connecting base is arranged at a peripheral portion on another lateral side of the circuit substrate to be electrically connected to the contacts. By means of the interface device, not only the connecting pins of the PMT can be protected from being damaged and generating high frequency noise but also the convenience for assembling or replacing the PMT can be improved.
    Type: Application
    Filed: March 31, 2008
    Publication date: October 1, 2009
    Inventors: Shih-Fan Yu, Tzong-Dar Wu, Meei-Ling Jan
  • Publication number: 20090236985
    Abstract: A photomultiplier tube 1 is an electron tube comprising an envelope 5 including a frame 3b having at least one end part formed with an opening and an upper substrate 2 airtightly joined to the opening, and a photocathode 6 contained within the envelope 5, the photocathode 6 emitting a photoelectron into the envelope 5 in response to light incident thereon from the outside; wherein multilayer metal films 10b, 10a each constituted by a metal film made of titanium, a metal film made of platinum, and a metal film made of gold laminated in this order are formed at the opening and the joint part between the upper substrate 2 and opening; and wherein the frame 3b and upper side substrate 2 are joined to each other by holding a joint layer 14 containing indium between the respective multilayer metal films 10b, 10a.
    Type: Application
    Filed: June 28, 2006
    Publication date: September 24, 2009
    Inventors: Hiroyuki Sugiyama, Keisuke Inoue, Hitoshi Kishita, Hideki Shimoi, Hiroyuki Kyushima
  • Patent number: 7592747
    Abstract: A photocathode, for generating electrons in response to incident photons in a photodetector, includes a base layer having a first lattice structure and an active layer having a second lattice structure and epitaxially formed on the base layer, the first and second lattice structures being sufficiently different to create a strain in the active layer with a corresponding piezoelectrically induced polarization field in the active layer, the active layer having a band gap energy corresponding to a desired photon energy.
    Type: Grant
    Filed: February 9, 2005
    Date of Patent: September 22, 2009
    Assignee: The United States of America as represented by the National Aeronautics and Space Administration
    Inventors: Robert A. Beach, Shouleh Nikzad, Robert P. Strittmatter, Lloyd Douglas Bell
  • Publication number: 20090230291
    Abstract: A photomultiplier tube is susceptible to noise at a low concentration and to saturation at a high concentration. It is necessary to make a measurement with an appropriate intensity of light to provide good reproducibility and linearity. Only adjustment of reagent concentration and constituents are not sufficient to apply the photomultiplier tube to a wide range of concentration. When the sensitivity of the photomultiplier tube is to be adjusted by voltage, measurement is performed under the optimum condition by setting a voltage to be applied suitable for measurement according to a concentration range specified for measurement items and adjusting the voltage based on selected items, previous values for the selected items, diagnostic information, etc.
    Type: Application
    Filed: February 18, 2009
    Publication date: September 17, 2009
    Inventors: Taku SAKAZUME, Kantaro Suzuki
  • Publication number: 20090218944
    Abstract: The present invention relates to a photomultiplier having a fine configuration capable of realizing stable detection accuracy. The photomultiplier has a housing whose inside is maintained vacuum, and a photocathode, an electron-multiplier section, and an anode are disposed in the housing. In particular, one or more control electrodes disposed in an internal space of the housing which surrounds the electron-multiplier section and the anode are electrically connected via one or more connection parts extending from an electron emission terminal of the electron-multiplier section.
    Type: Application
    Filed: June 1, 2006
    Publication date: September 3, 2009
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Hiroyuki Sugiyama, Hitosha Kishita, Suenori Kimura, Yuji Masuda, Takayuki Ohmura
  • Publication number: 20090160332
    Abstract: A vacuum vessel is configured by hermetically joining a faceplate to one end of a side tube and a stem to the other end via a tubular member. A photocathode, a focusing electrode, dynodes, a drawing electrode, and anodes are arranged within the vacuum vessel. The dynodes and the anodes have a plurality of channels in association with each other. Each electrode has cutout portions that overlap in a stacking direction, and supporting pins and lead pins are arranged in the cutout portions. A bridge is provided in a concave section arranged between unit anodes, and the bridge is cut off after the anode plate is placed on stem pins. Effective areas of each electrode and the anode are secured sufficiently, thereby allowing electrons to be detected efficiently.
    Type: Application
    Filed: February 27, 2007
    Publication date: June 25, 2009
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Hideki Shimoi, Koji Nagura, Hiroyuki Kyushima
  • Publication number: 20090127642
    Abstract: A photoelectric element 10 includes a substrate 12 that transmits incident light, an intermediate layer 14 made of HfO2, an under layer 16, and a photoelectron emitting layer 18 containing an alkali metal. That is, the photoelectric element 10 includes the intermediate layer 14 formed between the substrate 12 and the photoelectron emitting layer 18. Thereby, a photoelectric element that can exhibit a high value of effective quantum efficiency, an electron tube including the same, and a method for producing a photoelectric element are realized.
    Type: Application
    Filed: March 5, 2007
    Publication date: May 21, 2009
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Shinichi Yamashita, Hiroyuki Watanabe, Hideaki Suzuki, Kengo Suzuki
  • Patent number: 7498741
    Abstract: The present invention relates to a photomultiplier having a structure for performing a high gain and achieving a higher productivity in a state keeping or improving an excellent high-speed response. In the photomultiplier, an electron-multiplying unit accommodated in a sealed container has a structure that enables an integrated assembly of a focusing electrode, an accelerating electrode, a dynode unit, and an anode. Specifically, the accelerating electrode composes a lower electrode and an upper electrode fixed each other by welding at a plurality of spots. The lower electrode is held at a pair of insulating support members in a state for the pair of insulating support members to grasp unitedly it together with the dynode unit and anode. Additionally, the upper electrode has one or more slit grooves for pinching a part of the pair of insulating support members.
    Type: Grant
    Filed: October 28, 2005
    Date of Patent: March 3, 2009
    Assignee: Hamamatsu Photonics K.K.
    Inventor: Toshikazu Fujita
  • Patent number: 7495223
    Abstract: A photomultiplier tube, a photomultiplier tube unit, and a performance-improved radiation detector for increasing a fixing area of a side tube in a faceplate while increasing an effective sensitive area of the faceplate. In the photomultiplier tube, a side face (3c) of the faceplate (3) protrudes outward from an outer side wall (2b) of a metal side tube (2), so that a light receiving area for receiving light passing through a light receiving face (3d) of the faceplate (3) is increased. The overhanging structure of the faceplate (3) is conceived based on a glass refractive index. The overhanging structure is aimed to receive light as much as possible which has not been received before. When the metal side tube (2) is fused to the glass faceplate (3), a fusing method is adopted due to joint between glass and metal. Joint operation between the faceplate (3) and the side tube (2) is reliably ensured. Accordingly, the overhanging structure of the faceplate (3) is effective.
    Type: Grant
    Filed: September 7, 2007
    Date of Patent: February 24, 2009
    Assignee: Hamamatsu Photonics K. K.
    Inventors: Hideki Shimoi, Akira Atsumi, Hiroyuki Kyushima
  • Patent number: 7495392
    Abstract: This invention relates to an electron multiplier unit and others enabling cascade multiplication of electrons through successive emission of secondary electrons in multiple stages in response to incidence of primary electrons. The electron multiplier unit has a first support member provided with an inlet aperture for letting primary electrons in, and a second support member located so as to face the first support member. The first support member is provided with a focusing electrode functioning to alter trajectories of the primary electrons, in order to guide the primary electrons to the inlet aperture. These first and second support members hold an electron multiplication section for the cascade multiplication and an anode.
    Type: Grant
    Filed: July 15, 2005
    Date of Patent: February 24, 2009
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Kimitsugu Nakamura, Yousuke Oohashi, Keiichi Ohishi, Masuo Ito
  • Publication number: 20090045741
    Abstract: The present invention relates to a photomultiplier having a fine structure capable of realizing high detection accuracy by effectively suppressing cross talk among electron-multiplier channels. The photomultiplier comprises a housing whose inside is maintained vacuum, and, in the housing, a photocathode, an electron-multiplier section, and anodes are disposed. The electron-multiplier section has groove portions for cascade-multiplying photoelectrons as electron-multiplier channels, and the anodes are constituted by channel electrodes corresponding to the groove portions respectively defined by wall parts. In particular, at least parts of the respective channel electrodes are located in spaces sandwiched between pairs of wall parts defining the corresponding groove portions.
    Type: Application
    Filed: June 1, 2006
    Publication date: February 19, 2009
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Hiroyuki Sugiyama, Hitoshi Kishita, Suenori Kimura, Yuji Masuda, Takayuki Ohmura
  • Patent number: 7492097
    Abstract: This invention relates to an electron multiplier unit and others enabling cascade multiplication of electrons through successive emission of secondary electrons in multiple stages in response to incidence of primary electrons. The electron multiplier unit has a first support member provided with an inlet aperture for letting primary electrons in, and a second support member located so as to face the first support member. These first and second support members hold an electron multiplication section for the cascade multiplication and an anode. The electron multiplication section is comprised of at least a first dynode of a box type and a second dynode having a reflection type secondary electron emission surface located so as to face the first dynode and arranged to receive secondary electrons from the first dynode and to emit secondary electrons to a side where the first dynode is located.
    Type: Grant
    Filed: March 16, 2005
    Date of Patent: February 17, 2009
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Kimitsugu Nakamura, Yousuke Oohashi, Keiichi Ohishi, Masuo Ito
  • Patent number: 7489077
    Abstract: A glass container has a faceplate, a side tube, and a bottom. A photocathode is formed on the inner side of the faceplate. The glass container includes a partitioning wall, a shield electrode, a first dynode, a second dynode, a dynode array, and an anode. The partitioning wall has a cross shape to divide an electron focusing space into four space segments. The shield electrode is provided to shield the second dynode from the photocathode. A Venetian blind type of dynodes is provided as the dynode array. The first dynode, the second dynode, the dynode array, and the anode are maintained at the potential which is higher than that of the photocathode. Electrons emitted from the photocathode in response to incident light thereon efficiently impinge on the dynodes regardless of where the electrons are emitted. The electrons are multiplied and then detected by the anode.
    Type: Grant
    Filed: March 24, 2004
    Date of Patent: February 10, 2009
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Suenori Kimura, Takayuki Ohmura, Teruhiko Yamaguchi, Masuo Ito
  • Patent number: 7486021
    Abstract: A photocathode is formed on a predetermined portion of the internal surface of an envelope of an electric tube. An avalanche photodiode (APD) is provided inside the envelope. The APD is surrounded by a cover and a tubular inner wall. A manganese bead and an antimony bead serving as evaporation sources are disposed in the vicinity outside the inner wall. The manganese bead and the antimony bead are surrounded by a tubular outer wall. The manganese bead and the antimony bead generate metal vapor to thereby form the photocathode. In forming the photocathode, the cover, inner wall, outer wall prevent the metal vapor from being deposited on the APD or an unintended portion inside the electron tube.
    Type: Grant
    Filed: September 9, 2004
    Date of Patent: February 3, 2009
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Yasuhara Negi, Atsushi Uchiyama, Yasuyuki Egawa, Hiroyuki Kyushima, Suenori Kimura, Motohiro Suyama
  • Patent number: 7449834
    Abstract: The present invention relates to a photomultiplier that realizes significant improvement of response time properties with a structure enabling mass production. The photomultiplier comprises an electron multiplier section for cascade-multiplying photoelectrons emitted from said photocathode. The electron multiplier has a structure holding at least two dynode sets while sandwiching the tube axis of a sealed container in this the electron multiplier is housed. In particular, the first dynodes respectively belonging to the two dynode sets are arranged such that their back surfaces opposing respective secondary electron emitting surfaces face each other while sandwiching the tube axis. In this arrangement, because each first dynode itself is positioned near the tube axis, the efficiency of collection of photoelectrons arriving at the periphery of the first dynode is improved significantly.
    Type: Grant
    Filed: November 8, 2006
    Date of Patent: November 11, 2008
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Takayuki Ohmura, Suenori Kimura
  • Patent number: 7446327
    Abstract: Apparatus for amplifying a stream of primary charged particles comprises a body defining a chamber and an entrance aperture for receiving the stream of primary charged particles into the chamber, and an incident dynode, adapted to be charged to a pre-determined electrical potential, having a surface positioned in the chamber to be impacted by said primary charged particles at an angle of incidence greater than 30° from the surface normal and in response to the impact to generate a stream of secondary charged particles.
    Type: Grant
    Filed: April 21, 2006
    Date of Patent: November 4, 2008
    Assignee: ETP Electron Multipliers Pty Ltd.
    Inventor: Richard W. Stresau
  • Publication number: 20080265768
    Abstract: A gating large area hybrid photomultiplier tube that includes an envelope, a photocathode for emitting electrons in correspondence with incident light entering the envelope, a collecting anode having a semiconductor device which has an electron incident surface for receiving photoelectrons emitted from the photocathode, a gating grid for gating the photoelectrons emitted from the photocathode, an electron optical system for focusing and directing the photoelectrons generated by the photocathode toward the electron incident surface, and an ion target for collecting positive ions from the photoelectrons. The envelope has a first opening and a second opening; the photocathode is disposed at the first opening, while the collecting anode is disposed at the second opening of the envelope.
    Type: Application
    Filed: April 26, 2007
    Publication date: October 30, 2008
    Inventors: Vincent Michael Contarino, Pavlo Molchanov
  • Publication number: 20080265769
    Abstract: A large area hybrid photomultiplier tube that includes a photocathode for emitting photoelectrons in correspondence with incident light, a semiconductor device having an electron incident surface for receiving photoelectrons from the photocathode, and a cone shaped container. The container has a first opening and a second opening. The photocathode is disposed at the first opening, and the semiconductor device is disposed at the second opening.
    Type: Application
    Filed: April 26, 2007
    Publication date: October 30, 2008
    Inventors: Vincent Michael Contarino, Pavlo Molchanov
  • Patent number: 7417235
    Abstract: A multi-purpose efficient charge particle detector that by switching bias voltages measures either secondary ions, or secondary electrons (SE) from a sample, or secondary electrons that originate from back scattered electrons (SE3), is described. The basic version of the detector structure and two stripped down versions enable its use for the following detection combinations: The major version is for measuring secondary ions, or secondary electrons from the sample, or secondary electrons due to back-scattered electrons that hit parts other than the sample together or without secondary electrons from the sample. Measuring secondary ions or secondary electrons from the sample (no SE3). Measuring secondary electrons from the sample and/or secondary electrons resulting from back-scattered electrons hitting objects other than the sample (no ions).
    Type: Grant
    Filed: May 11, 2006
    Date of Patent: August 26, 2008
    Assignee: El-Mul Technologies, Ltd.
    Inventors: Armin Schon, Eli Cheifetz, Semyon Shofman
  • Publication number: 20080088234
    Abstract: The present invention relates to a photomultiplier that realizes significant improvement of response time properties with a structure enabling mass production. The photomultiplier comprises a sealed container, and, in the sealed container, a photocathode, at least one dynode set, a dynode unit including a part of insulating supporting members holding the one dynode unit, and a gain control unit are housed. The gain control unit has an insulating base plate, and the insulating base plate is integrally fixed with a control dynode and a final stage dynode that belong to each dynode set together with an anode. By the insulating base plate thus being clamped by the pair of insulating supporting members, the anode, the control dynode, and the final stage dynode constitute a part of an electron multiplier section.
    Type: Application
    Filed: November 8, 2006
    Publication date: April 17, 2008
    Inventors: Takayuki Ohmura, Teruhiko Yamaguchi
  • Patent number: 7342216
    Abstract: A photomultiplier system includes a detector tube, a power supply unit, and a thermal isolation element. The power supply unit provides an accelerating voltage for operating the detector tube. The detector tube and the power supply unit are disposed on different sides of the thermal isolation element.
    Type: Grant
    Filed: February 22, 2006
    Date of Patent: March 11, 2008
    Assignee: Leica Microsystems CMS GmbH
    Inventors: Roland Seifert, Juergen Schneider
  • Patent number: 7332700
    Abstract: In a photomultiplier tube (PMT) device having a plurality of dynodes provided between a cathode and an anode, a cancellation circuit provides two different modulation signals to the PMT to cancel the effects of the modulation signals upon the output of the PMT. For one embodiment, a cancellation circuit includes an input to receive an input modulation signal, a first output to provide a first output modulation signal to a first dynode, and a second output to provide a second output modulation signal to a second dynode, wherein the first and second output modulation signals are 180 degrees out-of-phase. For another embodiment, the cancellation circuit provides the input modulation signal to one of the PMT's dynodes, and also subtracts the input modulation signal from the PMT's output signal.
    Type: Grant
    Filed: April 26, 2005
    Date of Patent: February 19, 2008
    Inventors: Bruce Masato Ishimoto, Tim Hawks
  • Publication number: 20080018246
    Abstract: The present invention relates to a photomultiplier of a fine structure that realizes a high multiplier efficiency. The photomultiplier comprises an outer casing whose interior is maintained at vacuum, and, in the outer case, a photocathode that emits photoelectrons in response to incident light, an electron multiplier section that performs cascade multiplication of the photoelectrons emitted from the photocathode, and an anode for taking out secondary electrons, which are generated at the electron multiplier section, are arranged. In particular, groove portions for performing cascade multiplication of electrons from the photocathode are provided in the electron multiplier section, and on the respective surfaces of each pair of wall portions that define the groove portions are provided with one or more protrusions each having a secondary electron emitting surface formed on the surface thereof.
    Type: Application
    Filed: February 16, 2005
    Publication date: January 24, 2008
    Applicant: HAMAMATSU PHOTONICS K.K.
    Inventors: Hiroyuki Kyushima, Hideki Shimoi, Akihiro Kageyama, Keisuke Inoue, Masuo Ito
  • Patent number: 7317283
    Abstract: The present invention relates to a photomultiplier having a structure for performing a high gain and achieving a higher productivity in a state keeping or improving an excellent high-speed response. In the photomultiplier, an electron-multiplying unit accommodated in a sealed container has a structure that enables an integrated assembly of a focusing electrode, an accelerating electrode, a dynode unit, and an anode. Specifically, the focusing electrode has one or more notched portions to be grasped by a part of each of the insulating support members for grasping directly the dynode unit and so on when the focusing electrode itself is rotated around the tube axis of the sealed container. With this construction, the focusing electrode is fixed to the pair of insulating support members in a state that the focusing electrode is aligned with high accuracy by using the pair of insulating support member as a reference member.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: January 8, 2008
    Assignee: Hamamatsu Photonics K.K.
    Inventor: Toshikazu Fujita
  • Patent number: 7285783
    Abstract: A side tube includes a tube head, a funnel-shaped connection neck, and a tube main body, which are arranged along a tube axis and which are integrated together into the side tube. The size of a cross section of the tube head perpendicular to the tube axis is larger than the size of a cross section of the tube main body perpendicular to the tube axis. The radius of curvature of rounded corners of the tube head is smaller than the radius of curvature of rounded corners of the tube main body. The length of the tube head along the tube axis is shorter than the length of the tube main body along the tube axis. One surface of a faceplate is connected to the tube head. A photocathode is formed on the surface of the faceplate in its area located inside the tube head.
    Type: Grant
    Filed: February 4, 2004
    Date of Patent: October 23, 2007
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Teruhiko Yamaguchi, Suenori Kimura, Minoru Suzuki, Yoshitaka Nakamura
  • Publication number: 20070241680
    Abstract: The present invention relates to a photomultiplier having a configuration for improving response time characteristics. The photomultiplier comprises at least a sealed container, a photocathode, and an electron multiplier section. The electron multiplier section has an upper unit and a lower unit. The upper unit includes a focusing electrode, a mesh electrode, and a first dynode, among a multiple stages of dynodes, being a dynode at which the photoelectrons from the photocathode arrive. The lower unit includes the subsequent dynodes while excluding the first dynode from the multiple stages of dynodes, and a pair of insulating supporting members that clampingly hold the subsequent dynodes. The mesh electrode is positioned in an inclined state with respect to a tube axis.
    Type: Application
    Filed: April 13, 2007
    Publication date: October 18, 2007
    Inventors: Takayuki Ohmura, Suenori Kimura
  • Publication number: 20070241678
    Abstract: The present invention relates to a photomultiplier having a configuration for improving response time characteristics. The photomultiplier comprises at least a sealed container, a photocathode, and an electron multiplier section. The electron multiplier section has an upper unit and a lower unit. The upper unit includes a focusing electrode, a mesh electrode, and a first dynode. The lower unit includes the subsequent dynodes excluding the first dynode and a pair of insulating supporting members. The upper unit further includes partitioning plates for partitioning effective regions for plural electron multiplier channels that are assigned along the longitudinal direction of said first dynode in order to prevent crosstalk among the adjacent electron multiplier channels.
    Type: Application
    Filed: April 13, 2007
    Publication date: October 18, 2007
    Inventors: Takayuki Ohmura, Teruhiko Yamaguchi
  • Publication number: 20070241677
    Abstract: The present invention relates to a photomultiplier having a configuration for improving response time characteristics. The photomultiplier comprises at least a sealed container, a photocathode, and an electron multiplier section. The electron multiplier section has an upper unit and a lower unit. The upper unit includes a focusing electrode, a mesh electrode, and a first dynode. The lower unit includes the subsequent dynodes excluding the first dynode and a pair of insulating supporting members. The length in the longitudinal direction of the first dynode is made greater than the interval between the pair of insulating supporting members. By this configuration, the sizes of the effective regions of the assigned electron multiplier channels can be set arbitrarily without being restricted by the pair of insulating supporting members.
    Type: Application
    Filed: April 13, 2007
    Publication date: October 18, 2007
    Inventors: Takayuki Ohmura, Teruhiko Yamaguchi
  • Publication number: 20070241679
    Abstract: The present invention relates to a photomultiplier having a configuration for improving response time characteristics. The photomultiplier comprises a sealed container, a photocathode, and an electron multiplier section. The electron multiplier section has an upper unit and a lower unit. The upper unit includes a focusing electrode, a mesh electrode, and a first dynode. The lower unit includes the subsequent dynodes excluding the first dynode and a pair of insulating supporting members. The second dynode, belonging to the subsequent dynodes, is provided with a notch for partitioning effective regions for two adjacent electron multiplier channels. By this configuration, a sufficient discharge withstand voltage can be secured without having to modify electron trajectories.
    Type: Application
    Filed: April 13, 2007
    Publication date: October 18, 2007
    Inventors: Takayuki Ohmura, Suenori Kimura
  • Patent number: 7276704
    Abstract: A photomultiplier tube, a photomultiplier tube unit, and a performance-improved radiation detector for increasing a fixing area of a side tube in a faceplate while increasing an effective sensitive area of the faceplate. In the photomultiplier tube, a side face (3c) of the faceplate (3) protrudes outward from an outer side wall (2b) of a metal side tube (2), so that a light receiving area for receiving light passing through a light receiving face (3d) of the faceplate (3) is increased. The overhanging structure of the faceplate (3) is conceived based on a glass refractive index. The overhanging structure is aimed to receive light as much as possible which has not been received before. When the metal side tube (2) is fused to the glass faceplate (3), a fusing method is adopted due to joint between glass and metal. Joint operation between the faceplate (3) and the side tube (2) is reliably ensured. Accordingly, the overhanging structure of the faceplate (3) is effective.
    Type: Grant
    Filed: May 8, 2000
    Date of Patent: October 2, 2007
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hideki Shimoi, Akira Atsumi, Hiroyuki Kyushima
  • Patent number: 7238928
    Abstract: The edges of portions of a base member that are joined to stem pins are arranged as bottom surfaces of recesses formed in the stem so that the stem pins are joined to the base member at gradual angles and so that even when a bending force acts on the stem pins, the stem pins will contact the peripheral portions at the open sides of the recesses, thereby preventing further bending of the stem pins and preventing the forming of cracks at both sides of the portions at which the stem pins are joined to the base member. Furthermore, triple junctions, at which the conductive stem pins, the insulating base member to which the stem pins are joined, and vacuum intersect, are positioned inside the recesses and put in concealed-like states.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: July 3, 2007
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hideki Shimoi, Hiroyuki Kyushima
  • Patent number: 7189956
    Abstract: In a photomultiplier, a ring-like side tube is not interposed between a side tube and a stem in the radial direction, and the side tube is joined to the ring-like side tube in a state of being directly capped onto a portion of the stem that protrudes out from an open end face at the upper side of the ring-like side tube. The enlargement of the photomultiplier in the radial direction due to overlapping of the side tube and the ring-like side tube can thereby be restricted and a high density, a high degree of integration, etc., can be realized in mounting the photomultiplier.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: March 13, 2007
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hideki Shimoi, Hiroyuki Kyushima
  • Patent number: 7141926
    Abstract: Photomultiplier tubes with improved collection of incident radiation, especially from the periphery of the front face of the tube, and that more efficiently couple the collected radiation to the photocathode, and moreover have higher packing densities when assembled into arrays, resulting in enhanced imaging characteristics. The improvements in radiation collection and photomultiplier tube packing density are gained by a combination of several features including: tapering the edges of the faceplate so that the faceplate subtends an area as large or larger than any other cross-sectional area of the photomultiplier tube; forming the junction between the faceplate and metal tube on the underside of the faceplate, and in such a manner as to avoid obscuring the optical path between the incident radiation and photocathode; and utilizing the tapered edge of the faceplate as a reflector to couple radiation incident on the periphery of the faceplate to the photocathode.
    Type: Grant
    Filed: August 10, 2004
    Date of Patent: November 28, 2006
    Assignee: Burle Technologies, Inc.
    Inventors: Charles M. Tomasetti, Scott C. Moulzolf
  • Patent number: 7135670
    Abstract: Onto a base member, through which stem pins are passed and holding members are to be joined to the respective surfaces thereof, the stem pins and the holding members are joined by fusion by melting of the base member to arrange a stem with at least three or more layers formed by sandwiching the base member by the holding members. In comparison to a conventional arrangement wherein the stem is arranged as a single layer of glass material and this is melted to fuse the stem pins, the positional precision, flatness, and levelness of both surfaces of the stem are improved.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: November 14, 2006
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hideki Shimoi, Hiroyuki Kyushima
  • Patent number: 7132639
    Abstract: A holding member or a base member, through which stem pins are passed and one surface of which is held by the holding member, is joined to the stem pins and the holding member by fusion by the melting of the base member. Upon melting, a volume of the base member is made to escape into a base member seep portion, and a stem is arranged as a two-layer arrangement formed by the holding of the base member by the holding member. When the holding member is joined to the inner surface of the base member, the inner surface of the stem is improved in positional precision, flatness, and levelness, while when the holding member is joined to the outer surface of the base member, the outer surface of the stem is improved in positional precision, flatness, and levelness.
    Type: Grant
    Filed: July 26, 2005
    Date of Patent: November 7, 2006
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hideki Shimoi, Hiroyuki Kyushima
  • Patent number: 7109467
    Abstract: A gating module for gating an image intensifier tube. The gating module includes a frequency generator generating a base signal having a base frequency. A modulator spread-spectrum modulates the base frequency of the base signal to generate a modulated signal. A gating circuit coupled to the modulator generates a gating signal in response to the modulated signal.
    Type: Grant
    Filed: January 26, 2004
    Date of Patent: September 19, 2006
    Assignee: ITT Manufacturing Enterprises, Inc.
    Inventors: Richard Allen Kominsky, Jerry Raymond Long, James Hoge Bowen
  • Patent number: 7102284
    Abstract: In a photomultiplier, focusing pieces of a focusing electrode are formed with sufficient height that the photocathode in the adjacent channels cannot be viewed from the first and second stage dynodes of each channel in order to prevent light reflected from the first and second stage dynodes from returning to the adjacent channels. This construction prevents the photocathode from emitting undesired electrons, thereby suppressing crosstalk. Further, by arranging condensing lenses on the outer surface of a light-receiving faceplate in correspondence with each channel, light is reliably condensed in each channel. Further, an oxide film formed over the surface of the focusing pieces prevents the reflection of light off the focusing pieces.
    Type: Grant
    Filed: February 22, 2002
    Date of Patent: September 5, 2006
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Hisaki Kato, Hideto Kawai
  • Patent number: 7071604
    Abstract: An electron gun (10) includes an electron multiplier (22, 22?, 22?, 110) has a receiving end (50, 50?, 50?) for receiving primary electrons and an output end (54, 54?, 54?) that emits secondary electrons responsive to primary electrons arriving at the receiving end. An electron emitter (20, 20?, 20?, 102) is arranged at the receiving end of the electron multiplier for supplying primary electrons thereto. At least one of an electrical and a magnetic focusing component (14, 16) is arranged at the open output end of the electron multiplier for focusing the secondary electrons to define an electron beam. In a suitable embodiment, the electron multiplier includes a generally conical substrate (74, 90) and an electron mirror (52, 521, 522, 523, 921, 922) including a high secondary electron yield film (70) disposed on an outer surface of the conical substrate.
    Type: Grant
    Filed: February 13, 2003
    Date of Patent: July 4, 2006
    Assignee: GENVAC Aerospace Corporation
    Inventor: James A. Dayton, Jr.
  • Patent number: 7064485
    Abstract: A glass container has a faceplate, a side tube, and a bottom. A photocathode is formed on the inner side of the faceplate. The glass container includes a first dynode, a second dynode, a screen focusing electrode, a dynode array, and an anode. The screen focusing electrode consists of a first screen, a second screen, a flat plate, and an aperture. The first screen is provided on the first dynode side of the aperture and extends across the lower end of the first dynode towards the photocathode. The second screen is provided on the second dynode side of the aperture and extends across the lower end of the second dynode towards the photocathode. A Venetian blind type is provided as the dynode array. The first dynode, the second dynode, the dynode array, and the anode are maintained at the potential which is higher than that of the photocathode. Electrons emitted from the photocathode in response to incident light thereon efficiently impinge on the dynodes regardless of where the electrons are emitted.
    Type: Grant
    Filed: March 24, 2004
    Date of Patent: June 20, 2006
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Suenori Kimura, Takayuki Ohmura, Teruhiko Yamaguchi, Masuo Ito
  • Patent number: 7049747
    Abstract: An integrated micro-photomultiplier is disclosed which employs sub-micron-wide channels for electron amplification. These channels are created with standard lithographic and planar-fabrication techniques, and sealed with a vacuum-deposition process. A photocathode, continuous dynode, anode and signal-collector are fabricated along the channels. This photomultiplier design obviates the needs for through-substrate etching, and mechanical assembly of separate layers. Because large-scale-integration techniques can be used to fabricate multiple micro-photomultipliers, significant reductions in device cost and size are expected. The integrated micro-photomultiplier is useful for high-speed, low-light-level optical detection, and may find applications in optical communications, visible or infrared imaging, and chemical or biological sensing.
    Type: Grant
    Filed: June 26, 2003
    Date of Patent: May 23, 2006
    Assignee: Massachusetts Institute of Technology
    Inventors: James G. Goodberlet, Vemura H. S. Moorthy
  • Patent number: 7005625
    Abstract: A voltage divider network in combination with a voltage multiplier circuit voltage biases the electrodes of a photomultiplier tubes or related device. The circuit exploits the several voltage levels produced at successive stages of a voltage multiplier circuit in order to optimize the voltage divider network with respect to power consumption, current draw from the power supply, operating stability, and linear operation of the photomultiplier tube.
    Type: Grant
    Filed: December 6, 2004
    Date of Patent: February 28, 2006
    Assignee: Burle Technologies, Inc.
    Inventor: Paul A. Mitchell
  • Patent number: 7002132
    Abstract: The invention relates to a photocathode and the like having such structure for holding a photocathode plate on a light transparent member with good reliability and workability. In the photocathode, claw portions of a holding member fixed to the light transparent member is pressed against the lower surface of a supporting plate so that a photocathode plate is sandwiched between the light transparent member and the supporting plate. Thus, the supporting plate is pressed against the photocathode plate, so that the photocathode plate is pressed against the light transparent plate by the supporting plate. This allows the photocathode plate to be held reliably by the light transparent member. This simple configuration further provides good workability in assembling.
    Type: Grant
    Filed: November 12, 2003
    Date of Patent: February 21, 2006
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Yasuharu Negi, Yasuyuki Egawa, Toru Hirohata, Minoru Niigaki
  • Patent number: 6992441
    Abstract: A photocathode manufacturing intermediary article (24) includes a substrate layer (26), and an active layer (20) that is carried by the substrate layer (26). The active layer (20) includes photoemissive alkali antimonide material that is epitaxially grown on the substrate (26).
    Type: Grant
    Filed: September 13, 2004
    Date of Patent: January 31, 2006
    Assignee: Litton Systems, Inc.
    Inventors: Robert Glosser, Joseph P. Estrera, Loig E. Bourree
  • Patent number: 6989632
    Abstract: A photomultiplier has a dynode cascade arranged radially rather than axially. Effective dynode area thereby can increase through the cascade, leading to improved linearity of response, and the axial length of the device can be reduced. The dynodes are sections of a set of toroids and may be formed as a layer of secondary emissive material such as caesiated antimony on a monolithic sintered cast or otherwise moulded or machined block of insulating material. This novel form of dynode construction can also be used in other photomultiplier or electron multiplier configurations.
    Type: Grant
    Filed: November 30, 2001
    Date of Patent: January 24, 2006
    Assignee: Electron Tubes Limited
    Inventors: Anthony Bach, Ron McAlpine
  • Patent number: 6958474
    Abstract: A replaceable, electronically-isolated, MCP-based spectrometer detector cartridge with enhanced sensitivity is disclosed. A mass detector is electro-optically isolated from a charge collector with an electron multiplier for converting a charged particle into a multiplicity of electrons and a scintillator for converting the multiplicity of electrons into a multiplicity of photons. A light sensor is provided to convert the multiplicity of photons back into electrons which are summed into a charge pulse. The light sensor is realized by any of a plurality of photo-responsive devices.
    Type: Grant
    Filed: April 29, 2004
    Date of Patent: October 25, 2005
    Assignee: Burle Technologies, Inc.
    Inventors: Bruce Laprade, Ronald Starcher
  • Patent number: 6946792
    Abstract: A photomultiplier excellent in vibration resistance and improved in pulse linearity characteristic and time-response. The fourth, and sixth to ninth dynodes (Dy4, Dy6 to Dy9) have a similar shape to that of the second dynode (Dy2). The third and fifth dynodes (dy3, Dy5) are smaller than the dynode (Dy2). The first to tenth dynodes (Dy1 to Dy10) are so arranged that the dynode inner space path defined between opposed dynodes is perpendicular to the tube axis (X). The anode (A) is a mesh anode (A), and is opposed to the dynode (Dy2) with respect to the tube axis (X).
    Type: Grant
    Filed: July 19, 2001
    Date of Patent: September 20, 2005
    Assignee: Hamamatsu Photonics K.K.
    Inventors: Suenori Kimura, Masami Furuhashi, Tomohiro Ishizu, Masuo Ito