JPH04129154A - Electron conversion device - Google Patents

Abstract

PURPOSE:To enable high-speed blanking to be made at low voltage by providing a blanking unit combined with an electronic lens means within an electron conversion device, and directly deflecting a generated electron. CONSTITUTION:A blanking aperture 13 is made of a plate material having a circular opening at the center thereof, normally laid behind a blanking plate 12, and set at the same potential as the blanking plate 12. An electron emitted from a photoelectric conversion surface 4, therefore, is not deflected and arrives at a phosphor screen via the opening of the aperture 13, when there is no potential difference between the electrode plates 12a and 12b of the plate 12. When a potential difference of several volts is applied across the electrode plates 12a and 12b, the electron 2 is deflected, and the locus thereof deviates from the opening of the aperture 13, thereby being shut out with the aperture 13. According to the aforesaid construction, blanking can be made at high speed with less heat generation.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention relates to an electronic conversion device, and in particular, when observing the internal light emission of an LSI, it is possible to detect the light emission of a portion synchronized with the circuit operation of the LSI. It relates to electronic conversion devices used for observation.

(Prior Art) An example of a conventional electronic conversion device is shown in FIG. FIG. 3 shows an image intensifier, in which a photoelectric conversion surface 4 is provided on the front surface of a tube body 14 for receiving incident light or X-rays 1 and generating electrons according to the intensity of the incident light. Furthermore, a fluorescent surface 5 is provided on the rear surface of the tube body 14 for receiving and detecting electrons generated by the photoelectric conversion surface 4.

A blanking mechanism is provided in this electronic transducer to observe the operation over a short period of time.

This blanking mechanism includes an electron lens 3 that focuses and deflects the generated electrons between the photoelectric conversion surface 4 and the phosphor screen 5, and a multi-channel plate that applies a predetermined voltage to draw the generated electrons to the phosphor screen 5. (MCP)21. Then, a positive voltage is applied to the photoelectric conversion surface 4 of the MCP 21 by a power source 22, and the electrons generated on the photoelectric conversion surface 4 are focused and deflected by the electron lens 3 and attracted to the fluorescent screen 5.

The voltage normally applied to the MCP 21 is about 200 cm. Therefore, by turning on and off the voltage applied to the MCP 21 by the semiconductor switch 23 inserted between the power supply 22 and the MCP 21, the generated electrons are blanked. electrons no longer reach it.

As described above, in the conventional electronic conversion device, blanking was performed by turning on and off the voltage applied to the MCP using a switch provided outside the tube body 14 with a blanking mechanism.

(Problem to be solved by the invention) However, as mentioned above, in the conventional device, the MCP
Since the high voltage of 200V applied to the device was directly turned on and off using a switch, a semiconductor switch that could withstand high voltage and switch at high speed was required, but it was extremely difficult to obtain such a semiconductor switch. , even if obtained, it would be expensive.

Furthermore, as switching speeds increase, the switch driver generates more heat, which becomes more difficult to cool. Therefore, according to the conventional blanking method, the switching speed is limited to about 50 ns due to the high switching voltage and high resistance of the photocathode. Although this corresponds to 20 MHz, it is not fast enough to observe the internal operations of VLSIs and the like.

Moreover, the device for realizing high-speed switching also had the problem of requiring a large power supply, cooling device, etc.

The present invention was made in order to solve the above-mentioned problems, and an object of the present invention is to provide an electronic conversion device that enables high-speed blanking with a simple configuration. [Structure of the Invention] (Means for Solving the Problems) The present invention comprises a conversion means for generating electrons in response to a change in an electromagnetic wave signal, an electron lens means for focusing the electrons generated by the conversion means, and a focusing device. A blanking unit for controlling arrival of the generated electrons to the secondary conversion means is provided in combination with the electron lens means. It is characterized by

The blanking unit includes two electrode plates, and a blanking plate that deflects the generated electrons passing between the electrode plates by applying a potential difference thereto;
It is preferable to include a blanking aperture having an opening that allows the generated electrons that have passed through the blanking plate to pass when the blanking plate is not deflected, and blocks the generated electrons when the blanking plate is deflected.

(Function) In the present invention, a blanking unit provided in combination with the electronic lens means is provided inside the electronic conversion device.

Blanking is performed by directly deflecting the electrons generated from the photoelectric conversion means.

This enables high-speed blanking with low voltage.

(Embodiment) FIGS. 1 and 2 each show an embodiment of the present invention, with FIG. 1 showing an image converter and FIG. 2 showing a photomultiplier tube.

Note that FIGS. 4 and 5 show a conventional image converter and a photomultiplier tube corresponding to FIGS. 1 and 2, respectively.

The blanking unit shown in this embodiment has a blanking plate 12 consisting of two electrode plates 12a and 12b.
and a blanking aperture 13, and in the case of the image converter shown in FIG. 1, this blanking unit is inserted between the electronic lens 3.

In addition, in the case of the photomultiplier tube shown in FIG.
and the electron multiplier electrode 6.

The photomultiplier electrode 6 in the photomultiplier tube is used to multiply the generated electrons by reflecting them several times after the electrons 2 generated by the photoelectric conversion surface 4 are focused by the focusing electrode 9. It is something.

The electrons 7 multiplied in this way reach the anode 8 and are taken out as a signal from the external terminal 10.

Next, the present invention will be explained in detail.Since the function of the blanking unit of both the image converter shown in FIG. 1 and the photomultiplier tube shown in FIG. This will be done using an image converter.

In this device, the blanking plate 12 and the blanking aperture 13 directly turn on and off electrons generated on the photoelectric conversion surface 4. That is, the blanking aperture 13 is a plate member with a circular opening in the center, and is normally provided behind the blanking plate 12 and set to the same potential as the blanking plate 12. Therefore blanking plate 1
When there is no displacement difference between the two electrode plates 12a and 12b, the electrons emitted from the photoelectric conversion surface 4 pass through the opening of the blanking aperture 13 and reach the phosphor screen 5 without being deflected.

Here, the electrode plates 12a, 12 of the blanking plate 12
When a potential difference is applied between b, electrons 2 are deflected thereby, and as shown in the figure, the blanked electron trajectory 11 is shifted from the hole of the blanking aperture 13 and is blocked by the plate of the blanking aperture 13. . Therefore, the electrons do not reach the phosphor screen 5. This performs blanking.

FIG. 3 is a waveform diagram showing this state. By constantly applying a potential difference V and reducing the potential difference to 0 for a desired period ins, electrons will reach the phosphor screen during this period.

The same applies to the photomultiplier tube, and the blanking plate 12
When the electrons 2 are blocked by the blanking aperture 13 by applying a potential difference between the electrode plates 12a and 12b, the electrons do not reach the electron multiplier electrode 6, and therefore do not reach the anode 8, either, and the external terminal 10 The output of is in the off state.

The blanking unit according to the present invention may be installed at a position where it can blank the generated electrons before they reach the phosphor screen, and is not limited to the position shown in the embodiment. That is, depending on the structure of the electronic conversion device, it may be installed in combination with an electron lens means at a position where it can efficiently blank out focused generated electrons.

Furthermore, the present invention can be applied not only to the image converter and photomultiplier shown in the embodiments, but also to phototubes, image intensifiers, and the like.

〔Effect of the invention〕

As described above in detail based on the embodiments, in the present invention, a blanking unit is installed inside the electronic conversion device to directly blank the generated electrons.
It is no longer necessary to perform blanking by turning on and off the high voltage as in the past.

Therefore, blanking can be performed with a low voltage of about several volts, and a compact electronic conversion device that is high speed and generates little heat can be realized.

[Brief explanation of the drawing]

Fig. 1 is a block diagram of an image converter according to one embodiment of the present invention, Fig. 2 is a block diagram of a photomultiplier tube showing another embodiment, and Fig. 3 shows the voltage applied to the blanking plate. A waveform diagram, FIG. 4 is an explanatory diagram illustrating a blanking mechanism by a conventional electronic converter, and FIGS. 5 and 6 are configuration diagrams of the conventional electronic converter. 1... Incident light or X-ray, 2... Trajectory of electrons after photoelectric conversion, 3... Electron lens, 4... Photoelectric conversion surface, 5
... Fluorescent screen, 6... Electron multiplication electrode, 7... Multiplied electrons, 8... Anode, 9... Focusing electrode, 11...
・Blanked electron trajectory, 12...Blanking plate, 13...Blanking aperture, 1
4...Electronic conversion device.

Claims (1)

[Claims] 1. Conversion means for generating electrons in response to changes in electromagnetic wave signals; electron lens means for focusing the electrons generated by the conversion means; and two for extracting necessary information from the focused electrons. An electronic conversion device comprising secondary conversion means, characterized in that a blanking unit for controlling arrival of the generated electrons to the secondary conversion means is provided in combination with the electron lens means. 2. The blanking unit includes two electrode plates, and a blanking plate that deflects the generated electrons passing between the electrode plates by applying a potential difference thereto, and the generated electrons passing through the blanking plate. 2. The electronic conversion device according to claim 1, further comprising a blanking aperture having an opening that allows electrons to pass when the electrons are not deflected and blocks the electrons when the electrons are deflected.