JPH081796B2 - Photoelectric conversion tube - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photoelectric conversion tube such as a photomultiplier tube, and more particularly to a photoelectric conversion tube that detects a plurality of measuring lights independently and simultaneously and outputs them as electric signals.

[0002]

2. Description of the Related Art In fluorescence measurement using a microtiter plate (MTP), simultaneous photometry of a plurality of laser beams, etc., it is desired to measure a plurality of lights independently. In such a case, particularly in fluorescence measurement using a microtiter plate (MTP), since the output light is small, a photoelectric conversion tube is used, and light of multiple channels is independently detected. Has been proposed (for example, Japanese Patent Publication No. 59-3825).

[0003]

However, in the above-mentioned photoelectric conversion tube, the channel separation of the photocathode is not sufficient, so that there is a problem that the light of a plurality of channels cannot be independently detected with high accuracy. Therefore, it is an object of the present invention to provide a photoelectric conversion tube capable of increasing the independence of channels to reduce optical crosstalk and independently and precisely detecting light in each channel.

[0004]

In order to solve the above problems, according to the present invention, (a) each of a plurality of measurement incident lights is incident as a face plate of a photoelectric conversion tube.
(B) each of which is formed of a conductive metal having a plurality of holes
This is fitted into the hole of the face plate and
Providing a plurality of transparent portions having a photocathode deposited thereon,
(C) Increase the photoelectrons emitted from each of the photocathodes.
A plurality of electrode means for multiplying and converting into an electric signal is provided. Preferably, the light converging means is provided in each of the plurality of transparent portions. More preferably, the face plate has a coefficient of thermal expansion similar to that of the transparent portion, and is composed of iron / nickel / cobalt.
Including gold .

[0005]

When the incident light is incident on the transparent portion of the corresponding channel, photoelectrons are emitted from the photocathode formed on the back side of the transparent portion of the channel. The incident light of the adjacent channels has a transparent portion formed separately for each channel, and the photoelectric surface is attached to the output side (inner surface) corresponding to the transparent portion, so that the influence of the adjacent channel is eliminated. The photoelectrons emitted from the photocathode region on the output side of each transparent portion are converted into an electric signal by the electrode means arranged corresponding to the photocathode region and output from the photoelectric conversion tube. As a result, it is possible to perform measurement and photometry on a plurality of channels simultaneously and independently without being affected by optical crosstalk between adjacent channels. By disposing the light converging means in the transparent portion, the photoelectron collecting efficiency is improved and the optical crosstalk between the adjacent channels is significantly reduced. Since the face plate contains a conductive material having a coefficient of thermal expansion substantially the same as that of the transparent portion, the face plate becomes conductive and an electric current can be passed through the face plate. As a result, a current can also flow through the photocathode attached to the inner surface of the tube of the face plate.

[0006]

EXAMPLE As an example of the photoelectric conversion tube of the present invention, FIG. 1 is a sectional view of a multi-anode type photomultiplier tube, and FIG. 2A is a plane of a face plate of the multi-anode type photomultiplier tube of FIG. FIG. 2B shows a sectional view taken along line XX ′ in FIG. FIG. 3 shows a detailed enlarged view of the transparent portion 154 shown in FIG. The multi-anode type photomultiplier tube 100 includes a face plate 150, a photocathode 110 formed on an inner surface of the face plate 150,
A plurality of dynode sequences, eg, dynode sequence 120,
Further, it is provided with a plurality of anodes, for example, an anode 131, arranged at the output ends of the plurality of dynode rows.

The face plate 150 is made of an alloy "Kobaru alloy (trade name)" in which iron, nickel and cobalt are manufactured at a ratio of 54%, 29% and 17%, respectively. Cobalt alloy has a coefficient of thermal expansion of transparent parts 151 to 166.
The coefficient of thermal expansion of the glass is almost the same. Further, since the cobalt metal has conductivity, an electric current can be passed through the face plate 150. By applying an electric current to the face plate 150, the photocathode 110 adhered to the inner surface of the face plate 150.
Current also flows, and the current supply to the photocathode can be increased.

The face plate 150 is provided with 16 transparent portions 151 to 166. Transparent part 15
Nos. 1 to 165 are arranged corresponding to the incident positions of the incident light beams of a plurality of channels to be measured. In this embodiment, 16 channels of measurement light can be detected simultaneously and independently. Since 16 independent transparent portions 151 to 165 are formed on the face plate 150, holes 1 are formed in each transparent portion, for example, the transparent portion 154.
54a is opened, and the transparent glass 15 is placed in the perforated hole 154a.
Load 4c. The photocathode 110a is attached to the inner surface of the transparent glass 154c. In FIG. 3, the inner surface of the transparent glass 154c is rounded, and the photocathode 110a is formed on that surface.
Although the inner surface of the transparent glass 154c may be flat, the photocathode 110a is flat in this case.

16 sets of dynode rows are arranged facing the photocathode 110a of the transparent portion 154 and the photocathodes of the other transparent portions 151 to 153 and 155 to 156, respectively. For example, a dynode array 120 is arranged at the output end of the photocathode 110a on the inner surface of the transparent portion 154. In this dynode array 120, 10 dynodes are sequentially arranged in the axial direction of the multi-anode type photomultiplier tube 100. It is arranged. An anode 131 is arranged at the output end of the final dynode.

The light incident on the transparent portion 154 causes photoelectrons to be emitted from the photocathode 110a attached to the inner surface of the transparent portion 154, and the photoelectrons are incident on the first dynode 121 of the dynode array 120 to generate secondary electrons. Is converted into a multi-anode photoelectron multiplication signal as an electric signal at the anode 131 by the dynodes at the second and subsequent dynodes 122. Output to the outside of the double tube.
The light detection of other channels is similar to the above. The light detection of each channel is performed independently, and when the light of a plurality of channels is incident simultaneously, the light detection of each channel is independently performed simultaneously.

In implementing the present invention, various modifications other than those described above can be adopted. As the structure of the transparent portion, for example, as illustrated in FIG. 4, a light converging means, for example, a convex lens 154d may be attached in front of the transparent glass 154c in the transparent portion.
According to this structure, the light incident on the transparent portion 154 is converged by the convex lens 154d to further reduce the optical crosstalk between the adjacent channels, and also the photocathode 110.
Since the light incident on a is converged, the photoelectron collection efficiency is improved.

In the above-mentioned embodiments, the example in which the photoelectrons emitted from the photocathode are multiplied by the dynode and taken out as an electric signal via the anode has been described. However, when it is not necessary to multiply the photoelectrons, the dynode Need not be provided.

[0013]

As described above, according to the photoelectric conversion tube of the present invention, there is no optical crosstalk between channels, the measurement incident light is converged to generate a large photoelectron, and a plurality of measurement lights can be surely simultaneously emitted. Can be measured. According to the photoelectric conversion tube of the invention, the face plate is made of Cobalt metal,
An electric current can be passed through this face plate. Further, according to the photoelectric conversion tube of the present invention, the light converging means is provided in the transparent portion on which the measurement light is incident, whereby the optical crosstalk can be further reduced and the photoelectron collecting efficiency can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a multi-anode type photomultiplier tube as an example of a photoelectric conversion tube of the present invention.

2 (a) is a plan view of a face plate of the multi-anode type photomultiplier tube shown in FIG. 1, and FIG. 2 (b) is a sectional view taken along line XX ′ of FIG. 2 (a). is there.

FIG. 3 is a partially enlarged view of a transparent portion and a photocathode shown in FIGS. 2 (a) and 2 (b).

FIG. 4 is a partially enlarged view of a transparent portion and a photocathode according to another embodiment of the present invention.

[Explanation of symbols]

100 multi-anode type photomultiplier tube, 110 photocathode 120 dynode array 150 face plate 151-165 transparent part

Front page continued (72) Inventor Yoshizumi Atsumi 1 1126, Nomachi, Hamamatsu City, Shizuoka Prefecture, Hamamatsu Photonics Co., Ltd. (56) Reference JP-A-57-194445 (JP, A) JP-A-2-291653 ( JP, A) Actual development Sho 55-173070 (JP, U)

Claims (3)

[Claims] 1. A face plate formed of a conductive metal having a plurality of holes through which a plurality of measurement incident lights are respectively incident , and the face plates are fitted into the holes of the face plate , respectively.
A photoelectric conversion tube comprising : a plurality of transparent portions having a photocathode adhered to an inner surface thereof; and a plurality of electrode means for multiplying photoelectrons emitted from each of the photocathodes and converting the photoelectrons into an electric signal. 2. The photoelectric conversion tube according to claim 1, wherein a light converging means is provided in each of the transparent portions of the plurality of face plates. 3. The photoelectric conversion tube according to claim 1, wherein the face plate contains an iron-nickel-cobalt alloy having a coefficient of thermal expansion substantially the same as that of the transparent portion.