Hamamatsu-photonics K.k.

Hamamatsu Photonics Kabushiki Kaisha

Suenori Kimura

Masuo Ito

Takayuki Ohmura

Hiroyuki Kyushima

Motohiro Suyama

Yoshihiko Kawai

Atsuhito Fukasawa

Yasuyuki Egawa

Tetsuya Morita

Teruhiko Yamaguchi

Yasuharu Negi

Atsushi Uchiyama

Hidehiro Kume

Hideki Shimoi

Hiroyuki Sugiyama

Hitoshi Kishita

Norio Asakura

Yuji Masuda

Masumi Tachino

Ken Hirano

Takashi Goto

Yutaka Hasegawa

Minoru Suzuki

Tomohiro Ishizu

Yoshitaka Nakamura

Tetsuya Saito

Kimitsugu Nakamura

Hisaki Kato

Keiichi Ohishi

Yousuke Oohashi

Shunsuke Kobayashi

Kiyoshi Nakatsugawa

Hiroyuki Onda

Nobuyuki Ohsugi

Toshiharu Totsuka

Tsuguo Uchino

Itsuo Ozawa

Atsuhide Suzuki

Takayuki Omura

Takayasu Nagasawa

Yasuhara Negi

Masami Furuhashi

An electron tube includes a photoelectric conversion unit, an electron detection unit configured to receive a photoelectrons from the photoelectric conversion unit, a gate electrode disposed between the photoelectric conversion unit and the electron detection unit, and a housing configured to accommodate the photoelectric conversion unit, the electron detection unit, and the gate electrode. The housing has a lid portion to which the photoelectric conversion unit is fixed and which constitutes one end side of the housing. The gate electrode includes a main body portion that control passage of the photoelectrons by applying a voltage, and a power supply part that supports the main body portion so as to be spaced apart from the photoelectric conversion unit and applies a voltage to the main body portion. The power supply part is held by the lid portion.

Electron tube

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. In this configuration, due to a voltage, instead of the applying between an electron entrance terminal and the electron emission terminal of the electron-multiplier section, being applied between the electron entrance terminal and the control electrodes, an electric potential gradient which is increased gradually from the photocathode side toward the anode side is formed in the electron-multiplier section, and a sufficient electric potential difference is provided between the electron emission terminal of the electron-multiplier section and the anode, which makes it possible to obtain stable detection accuracy.

Photomultiplier

The present invention relates to a photomultiplier having a structure that enables to perform high gain and satisfy higher required characteristics. In the photomultiplier, an electron-multiplying unit accommodated in a sealed container comprises a focusing electrode, an accelerating electrode, a dynode unit, and an anode. Particularly, at least the accelerating electrode and dynode unit are held unitedly in a state that at least a first-stage dynode and a second-stage included in the dynode unit are opposite directly to the accelerating electrode not through a conductive material. A conventional metal disk for supporting directly dynodes which are set to the same potential as that of the first-stage dynode is not placed between the accelerating electrode and dynode unit; thus, variations of the transit time of electrons may be drastically reduced while the electrons reach from the cathode to the second-stage dynode via the first-stage dynode.

Photomultiplier including a photocathode and an accelerating electrode

The present invention relates to a photomultiplier having a fine structure capable of realizing high multiplication efficiency. The photomultiplier comprises a housing whose inside is maintained vacuum, and, on a device mounting surface which is a part of an inner wall surface defining an internal space of the housing, a photocathode serving as a reflection type photocathode, an electron-multiplier section, an anode, and a voltage distributing section are disposed integrally. In particular, the electron-multiplier section is constituted by dynodes at multiple stages cascade-multiplying photoelectrons from the photocathode, and the voltage distributing section, which applies corresponding voltages to the dynodes at the respective stages respectively, is on the same surface together with the electron-multiplier section.

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.

Photomultiplier including an electronic-multiplier section in a housing

A photomultiplier tube includes: a cathode, a plurality of dynodes, and an electron lens forming electrode. The cathode emits electrons in response to incident light. The plurality of dynodes multiplies electrons emitted from the cathode. The electron lens forming the electrode is disposed in a prescribed position in relation to an edge of a first dynode positioned in a first stage from the cathode and an edge of a second dynode positioned in a second stage from the cathode, and smoothes an equipotential surface in a space between the first dynode and the second dynode along a longitudinal direction of the first dynode. This structure improves time resolution in response to incident light.

Photomultiplier tube

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 the sealed container includes a hollow body section, extending along a tube axis, and a faceplate. The faceplate has a light incidence surface and a light emission surface on which a photocathode is formed. In particular, the light emission surface is constituted by a flat region, and a curved-surface processed region that is positioned at a periphery of the flat region and that includes edges of the light emission surface. A surface shape of the peripheral region of the light emission surface of the faceplate is thus intentionally changed in order to adjust the angles of emission of photoelectrons from the photocathode positioned at the peripheral region. Thus, the spread of transit times of photoelectrons propagating from the photocathode to a first dynode is thus reduced effectively and made not to depend on the emission positions of the photoelectrons.

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.

Multi-anode type photomultiplier tube and radiation detector

An envelope has a glass bulb body and a cylindrical glass bulb base. The glass bulb body includes an upper hemisphere and a lower hemisphere. The upper hemisphere is curved in a substantially spherical shape. The lower hemisphere is substantially curved in a spherical shape and connects the upper hemisphere and glass bulb base. A photocathode is formed on the inner surface of the glass bulb body. An avalanche photodiode is disposed on the glass bulb body side relative to an intersection between an imaginary extended curved surface of the lower hemisphere within the glass bulb base and an axis. When light enters the photocathode, electrons are emitted from the photocathode. The electrons are converged at the position above and in the vicinity of the APD by an electrical field in the electron tube, so that the electrons enter the APD in an efficient manner and are detected satisfactorily.

In an electron tube, an insulating tube protrudes inside an envelope. One end of the insulating tube is connected to the envelope. An avalanche photo diode (APD) is provided on the other end of the insulating tube. A ground voltage is applied to the envelope and a positive high voltage is applied to the APD. Photoelectrons which are emitted in response to an incident light on a photocathode are converged by an electrical field in the envelope and enter the APD. Thereafter, the incident photoelectrons are amplified and detected. Since a positive high voltage is not exposed to the envelope, the electron tube can easily be handled and is excellent in safety.

Electron tube with electron-bombarded semiconductor device

An insulating tube has one end and another end. An avalanche photodiode (APD) is provided outside the one end of the insulating tube. The another end of the insulating tube is air-tightly connected to an outer flange through a stem inner wall. Capacitors electrically connected to the APD are provided in the insulating tube. The capacitors remove direct current components from signals that the APD generates when detecting electrons. By providing the capacitors in the insulating tube, response of output signals can be prevented from being impaired.

Electron beam detection device and electron tube

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.

Multi-anode type photomultiplier tube

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.

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.

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Hamamatsu, Japan

Suenori Kimura