A gated photoelectric detector with large dynamic detection range and a control method thereof

Abstract

The present invention relates to a photoelectric detection device, and in particular to a gated photoelectric detector with a large dynamic detection range and a control method thereof. The present invention overcomes the shortcomings of the current scheme for improving the large dynamic range and gate function of photomultiplier tubes, such as loss of effective detection time, generation of gated noise and crosstalk noise, and complex internal structure of the photomultiplier tube. The present invention utilizes the characteristics of the secondary electron multiplication material used in the electron multiplication system of the photomultiplier tube and the quasi-linear distribution of the energy of the electrons incident on this material within a certain range, and by means of the cathode gated technology of the photomultiplier tube, applies a gated electric pulse signal with a slow time parameter between the cathode and the first electrode of the electron multiplication system, so that the photomultiplier tube realizes the gated function, and at the same time modulates the energy of the cathode-emitted electrons when they move to the first electrode of the electron multiplication system, changes the number of electrons generated after the first multiplication in the electron multiplication system, and achieves the linear multiplication characteristics of the electron multiplication system to realize the large dynamic range detection function.

Description

Technical Field

[0001] The invention relates to a photoelectric detection device, in particular to a gated photoelectric detector with a large dynamic detection range and a control method thereof. Background Art

[0002] With the rapid development of science and technology, higher requirements are placed on the range and accuracy of signal target detection in the fields of lidar systems, nuclear physics research, and high-energy physics research. It is necessary not only to detect the entire transformation process of the same target signal from strong to weak, but also to accurately detect the changes in optical signals within a certain time interval, so as to achieve a global grasp of the change process of the detection target and the purpose of local fine diagnosis, so as to understand the complete information of the signal more accurately and obtain a more comprehensive change process of the detection target.

[0003] The photomultiplier tube is a photoelectric detection device with high gain and high time resolution, which can effectively detect extremely weak light signals, so it is widely used in scientific research, medical treatment, national defense and other fields. In particular, the photomultiplier tube with a large detection dynamic range, low dark noise, fast response speed and gating function can better meet the detection needs of the above fields.

[0004] The gating function of the photomultiplier tube is generally achieved by means of internal and external gating of the photocathode and gating between the electron multiplier stages. The internal and external gating method of the photocathode is to control the direction of movement of the electrons emitted by the cathode to the electron multiplier electrode by changing the voltage difference between the cathode of the photomultiplier tube and the first electrode of the electron multiplier (the electrode closest to the cathode among all the electrodes in the electron multiplier system), and then control whether the electrons enter the electron multiplier electrode for multiplication to achieve the gating function of the photomultiplier tube. The dynamic detection range of the photomultiplier is mainly achieved by changing the working voltage of the electron multiplier electrode to reduce the electron multiplication gain, reading the signal from the electron multiplier electrode and the anode at the same time, and regulating the number of electrons emitted by the cathode entering the electron multiplier system.

[0005] The above scheme for realizing the photomultiplier gating and large dynamic detection range function has the following disadvantages: First, when realizing the photomultiplier tube gating function, in order to shorten the photomultiplier tube gating time, a gating electric pulse signal with a smaller time parameter is generally used to drive the photomultiplier tube, which not only generates a gating noise of a certain amplitude at the anode, but also requires nanoseconds for the photomultiplier tube to establish a stable working state, which not only introduces large noise but also wastes a certain amount of detection time. Secondly, to realize the large dynamic detection range of the photomultiplier tube, when the working voltage of the electron multiplication system is changed, the entire system needs a certain amount of time to establish a stable working state, thereby wasting effective detection time. When the output signal of the multiplier tube is read from the electrode multiplier and the anode at the same time, there is a certain signal crosstalk between each readout electrode, thereby generating corresponding crosstalk noise and reducing the signal-to-noise ratio of the photomultiplier tube detection. When the method of controlling the number of electrons is adopted, the difficulty of preparing the internal structure of the photomultiplier tube is bound to increase.

[0006] In summary, the above-mentioned scheme for realizing a large dynamic range and a gating function of a photomultiplier tube has the disadvantages of losing effective detection time, generating gating noise and crosstalk noise, and having a complex internal structure of the photomultiplier tube. Summary of the invention

[0007] In view of the shortcomings of current schemes for improving the large dynamic range and gating function of photomultiplier tubes, such as loss of effective detection time, generation of gating noise and crosstalk noise, and complex internal structure of the photomultiplier tube, the present invention provides a photodetector with a gating function and capable of achieving a large dynamic detection range.

[0008] The present invention is conceived as follows:

[0009] The present invention utilizes the characteristics of the photomultiplier tube electron multiplication system using secondary electron multiplication materials and the quasi-linear distribution of the energy of the electrons incident to the materials within a certain range, and applies a gated electric pulse signal with a slow time parameter between the cathode and the first electrode of the electron multiplication system by means of the photomultiplier tube cathode gating technology, so that the photomultiplier tube realizes the gating function, and at the same time modulates the energy of the cathode-emitted electrons when they move to the first electrode of the electron multiplication system, thereby changing the number of electrons generated after the first multiplication in the electron multiplication system, thereby achieving the linear multiplication characteristics of the electron multiplication system to realize a large dynamic range detection function, and at the same time can effectively reduce the gating noise of the photomultiplier tube and eliminate the corresponding crosstalk noise, greatly improving the signal-to-noise ratio of the multiplier tube. The use of this technology can realize that the dynamic range of the photomultiplier tube can be improved by more than ten times on the basis of realizing the gating function.

[0010] The technical solution of the present invention is:

[0011] A gated photoelectric detector with a large dynamic detection range comprises a cathode, an electron multiplication system, an anode, a power supply system, a gated pulse generator and a pulse feeding circuit; the cathode, the electron multiplication system and the anode are arranged in sequence along the electron transmission direction and are located in a vacuum environment; the power supply system is connected to the cathode, the electron multiplication system and the anode; the gated pulse generator is connected to the cathode through the pulse feeding circuit;

[0012] Its special features are:

[0013] The electron multiplication system described above uses secondary electron multiplication material to multiply the electrons generated by the cathode;

[0014] The gating pulse generator is used to generate a gating electrical pulse signal whose voltage amplitude decreases with time; the gating electrical pulse signal is a gating electrical pulse signal with a slow time parameter, ensuring that the time length required for detection is covered as much as possible;

[0015] The pulse feeding circuit is used to feed the selection electric pulse signal to the cathode to realize cathode voltage modulation and cathode emitted electron movement to electron multiplication system energy modulation.

[0016] Furthermore, the waveform of the above-mentioned gate electrical pulse signal is a triangle wave, a sine wave or a cosine wave.

[0017] Furthermore, the electron multiplying system may be a microchannel plate electron multiplying system, a dynode electron multiplying system, or the like.

[0018] Furthermore, the cathode may be an ultraviolet cathode, an infrared cathode, a visible light cathode or the like having good conductivity.

[0019] Furthermore, the anode may be a metal sheet anode, a conical anode, or the like.

[0020] Furthermore, the power supply system may be a resistor voltage-dividing power supply system, or a voltage-doubling power supply system, or a transformer power supply system, etc., whichever power supply system can satisfy the normal operation of the detector.

[0021] Furthermore, the pulse feeding circuit may be a separate electronic component or a circuit system.

[0022] The present invention also provides a control method for a gated photoelectric detector with a large dynamic detection range, which is special in that it comprises the following steps:

[0023] Step 1: The power supply system supplies power so that the cathode, the corresponding electrode of the electron multiplication system and the anode all have stable voltage values;

[0024] Step 2: Adjust the power supply system so that the cathode voltage is higher than the first electrode voltage of the electron multiplication system. The voltage difference between the two is Vc-d , the photodetector is in the cut-off state;

[0025] Step 3: trigger the strobe pulse generator to generate a strobe electrical pulse signal whose voltage amplitude decreases with time, and the minimum amplitude of the strobe electrical pulse signal is V g , V g The value range is V c-d +10 to V c-d +400;

[0026] When the cathode voltage is equal to the voltage of the first electrode of the electron multiplication system, the photodetector changes from the cut-off state to the gating state, realizing the gating function;

[0027] As the amplitude of the gating electric pulse signal further decreases, the energy of the electrons emitted by the cathode gradually increases, which makes the first secondary electron multiplication coefficient of the electron multiplication system gradually increase, and then the electron gain of the entire electron multiplication system increases, realizing dynamic adjustment of the photoelectric detection with low electron gain when the light intensity is strong and the dynamic increase of electron gain when the light intensity becomes weak, so that this device has a higher dynamic range.

[0028] The beneficial effects of the present invention are:

[0029] First, in the initial state of the photodetector, the cathode voltage is higher than the first electrode voltage of the electron multiplying system, and the photodetector is in a cut-off state. When the gating pulse generator is triggered to generate a gating voltage and applied to the cathode, the cathode voltage is close to the first electrode voltage of the electron multiplying system and then lower than the first electrode voltage of the electron multiplying system, so that the photodetector can normally realize the optical signal detection function and has a gating function.

[0030] Secondly, since the electron gain of the electron multiplication system is determined by the product of the gain coefficient of each electron multiplication, after the gating function is realized, the cathode voltage is continued to be reduced and the energy of the electrons emitted from the cathode is increased, so that the multiplication coefficient of this electron during the first electron multiplication increases, and the electron gain of the electron multiplier increases when the light intensity becomes weaker, thereby realizing that the detector has a low electron gain when the light is strong and a high electron gain when the light is weak, so that the dynamic range of the photoelectric detector is improved by more than ten times on the basis of realizing the gating function. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is the relationship curve between the secondary electron emission coefficient of the dynode and the electron energy.

[0032] Figure 2 It is a schematic diagram of the principle of the gated photoelectric detector with a large dynamic detection range of the present invention.

[0033] Figure 3 Schematic diagram of the principle of a photoelectric detector embodiment of the present invention.

[0034] Figure 4 This is a schematic diagram of the implementation process of the gating function of the photoelectric detector embodiment of the present invention. Where a is the photoelectric detector in the electronic cutoff state, and b is the photoelectric detector implementing the gating function;

[0035] Figure 5 Schematic diagram of the process of achieving variable gain by electronic energy modulation in a photodetector embodiment of the present invention.

[0036] Figure 6 Measurement curve of MCP photomultiplier tube with different incident electron energies and anode output pulse amplitude.

[0037] The reference numerals in the figure are: 1, cathode; 2, electron multiplication system; 3, anode. DETAILED DESCRIPTION

[0038] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is described in detail below in conjunction with the accompanying drawings.

[0039] The present invention utilizes the characteristics of the secondary electron multiplication material and the electron energy incident to the material in a certain range to present a quasi-linear distribution, such as Figure 1 As shown, the secondary electron multiplication coefficient of commonly used secondary electron multiplying materials, such as magnesium oxide, aluminum oxide, beryllium oxide, lead oxide, etc., basically changes linearly with the incident electron energy in the range of 0 to 200V. Of course, there will be slight differences in this range for different types of secondary electron multiplying materials. With the help of the cathode gating technology of the photomultiplier tube, a gating electric pulse signal with a slow time parameter is applied between the cathode and the first electrode of the electron multiplying system, so that the photomultiplier tube can realize the gating function, and at the same time modulate the energy of the cathode emitted electrons when they move to the first electrode of the electron multiplying system, thereby changing the number of electrons generated after the first multiplication of the electron multiplying system, thereby achieving the linear multiplication characteristics of the electron multiplying system to realize the large dynamic range detection function. The slow time parameter here mainly describes that the falling edge of the gating (for negative pulses) is relatively long, which is exactly the opposite of the "gating pulse with a smaller time parameter" required in the prior art. The present invention uses the gating electric pulse signal with slow time parameters mainly for the following two considerations: first, to ensure that the photomultiplier tube has a long detection time, covering the time length required for detection as much as possible, so that the photomultiplier tube can realize the gating function, and in the whole process, the electron energy incident to the electron multiplier is modulated to realize the function of large dynamic range detection; second, the gating electric pulse signal with slow time parameters can well suppress the gating noise. According to the test results of our existing gating photomultiplier tube, the faster the falling edge of the gating pulse (for negative pulses), the greater the gating noise of the photomultiplier tube.

[0040] like Figure 2As shown, the gated large dynamic detection range photoelectric detector proposed in the present invention mainly includes: a cathode 1, an electron multiplication system 2, an anode 3, a power supply system, a gated pulse generator and a pulse feeding circuit; wherein the cathode 1, the electron multiplication system 2 and the anode 3 are located in a vacuum environment; the cathode 1 realizes the photoelectric conversion of the photon signal; the electron multiplication system 2 is used to multiply the electrons generated by the cathode 1; the anode 3 is used to collect and output the electron beam after multiplication by the electron multiplication system 2; the power supply system realizes the power supply to the cathode 1, the electron multiplication system 2 and the anode 3; the gated pulse generator is used to generate a gated electrical pulse signal; the pulse feeding circuit is used to feed the gated electrical pulse signal generated by the gated pulse generator to the cathode 1. The cathode 1 can be a cathode with good conductivity such as an ultraviolet cathode, an infrared cathode, a visible light cathode, etc.; the electron multiplying system 2 can be an electron multiplying system such as a microchannel plate electron multiplying system, a dynode electron multiplying system, etc. that realizes electron multiplication by secondary electron multiplying materials; the anode 3 can be a metal sheet anode, a conical anode, etc.; the cathode 1, the electron multiplying system 2 and the anode 3 are all located in a vacuum environment and together constitute the tube body of the photodetector; the power supply system can be a resistor voltage divider power supply system, or a voltage doubler power supply system, a transformer power supply system, etc. that can meet the normal operation of the detector; the selection pulse generator is a pulse generator that can generate triangular wave, sine wave, cosine wave, etc. The amplitude of the electric pulse signal decreases with time; the pulse feeding circuit can be a separate electronic component, or it can be a circuit system, etc.

[0041] The function realization method of the gated photoelectric detector with large dynamic detection range described in the present invention is as follows:

[0042] according to Figure 2 The schematic diagram of the principle shown connects the tube body with the relevant electrical system, and the power supply system supplies power to the tube body, so that the cathode 1, the corresponding electrode of the electron multiplication system 2 and the anode 3 all have stable voltage values. At this time, the multiplication coefficient of the electrons entering the electron multiplication system 2 for the first electron multiplication is δ 1 , the multiplication factor of the secondary electron multiplication is δ 2 The multiplication factor of the third electron multiplication is δ 3 ..., the multiplication factor of the nth electron multiplication is δ n , the total electron gain of the electron multiplication system 2 is:

[0043] δ=δ 1 *δ 2 *δ 3 …*δ n

[0044] The power supply system is adjusted so that the voltage of cathode 1 is higher than the voltage of the first electrode of electron multiplication system 2 (the electrode closest to cathode 1 among all electrodes of electron multiplication system 2). The voltage difference between cathode 1 and the first electrode of electron multiplication system 2 is V c-d (amplitude is greater than 5 volts). At this time, the electric field between cathode 1 and the first electrode of electron multiplier system 2 causes the electrons emitted from cathode 1 to fail to move in the direction from cathode 1 to electron multiplier system 2, but to move toward cathode 1, thereby causing the photodetector to fail to multiply and output the signal electrons generated by cathode 1, and the electron multiplier is in a cut-off state.

[0045] When a strong light signal enters the cathode 1 of the photodetector, the gate pulse generator is triggered to generate a gate electrical pulse signal whose voltage amplitude decreases with time. The minimum amplitude of the gate electrical pulse signal is V g , V g The value range is V c-d +10 to V c-d +400. The gated electrical pulse signal is applied to cathode 1 through the pulse feed circuit, and is superimposed with the original voltage value of cathode 1 to form a new voltage value of cathode 1. The new voltage of cathode 1 also decreases gradually over time. When the voltage of cathode 1 is the same as the voltage value of the first electrode of electron multiplication system 2, the electrons emitted by cathode 1 can move to electron multiplication system 2. Since the electron energy is low at this time, the multiplication factor δ of the first electron multiplication of electrons by electron multiplication system 2 is 1 is low, so a large number of cathode 1 electrons can only produce a small number of first multiplication electrons for subsequent multiplication, which can make the electron multiplication system 2 in the linear multiplication region. As time goes on, the light intensity decreases, but the cathode 1 voltage is lower than the first electrode voltage of the electron multiplication system 2 and the voltage difference V between the two is c-d The absolute value of is getting bigger and bigger, and the energy of the electrons emitted by cathode 1 into electron multiplication system 2 (electron energy is e*|V c-d |, e is the electron charge) is also increasing. At this time, although the number of electrons emitted by the cathode 1 decreases, the electron multiplication coefficient δ of the electron multiplication system 2 for the first electron multiplication of electrons 1 It also increases with time, so that the number of electrons increases after the first electron multiplication. Since the structural conditions and electrical conditions of the second, third and nth electron multiplication processes have not changed, their electron multiplication coefficients remain unchanged. Therefore, although the number of electrons emitted by cathode 1 decreases as the light intensity weakens, the electron multiplication coefficient δ of the first electron multiplication increases. 1 The electronic gain of the entire electron multiplication system 2 is increased to ensure that the photoelectric detector can detect weak light signals and that the photoelectric detector has a large dynamic range detection function.

[0046] The following is a detailed description using a microchannel plate (MCP) as an electron multiplier tube device as an example. Obviously, the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. In the following description, many specific details are set forth to facilitate a full understanding of the present invention, but the present invention can also be implemented in other ways different from those described herein, and those skilled in the art can make similar generalizations without violating the connotation of the present invention. Therefore, the present invention is not limited by the specific embodiments disclosed below.

[0047] like Figure 3 As shown, the gated large dynamic detection range photoelectric detector of this embodiment is composed of a cathode 1, an electron multiplier system 2, an anode 3, a power supply system, a gated pulse generator and a pulse feeding circuit, wherein the electron multiplier system 2 is composed of a microchannel plate, which is a double MCP combination structure, and the cathode 1, the MCP group and the anode 3 constitute the tube body of the photoelectric detector, and the cathode 1, the MCP group and the anode 3 are all located in a vacuum environment, the distance between the cathode 1 and the input surface of the MCP group is 1 mm, and the distance between the MCP group and the anode 3 is 1 mm.

[0048] In this embodiment, the photodetector tube body is powered by a resistor voltage divider to ensure normal operation of the tube body. The MCP group adopts a two-electrode power supply method, with the input electrode voltage being V1 and the output electrode voltage being V2. Figure 3 The voltage difference Vc-V1 between the cathode voltage Vc and the MCP input voltage V1 is the voltage value of the Rb resistor, and V1 is less than Vc. The working voltage V2-V1 of the MCP group is the voltage value of the Rd resistor. The voltage difference between the MCP group output electrode voltage V2 and the anode is the voltage value of the Re resistor, and the anode is at zero potential. In this embodiment, Vc-V1=50V, V2-V1=1700V, and V2 is -200V. The gating pulse generator generates a negative triangular wave electric pulse under external triggering. The amplitude Vg(t) of this pulse decreases with time, and this gating electric pulse signal is input to the cathode electrode through a capacitor (pulse feeding circuit), and together with the original cathode working voltage Vc, it constitutes a new working voltage Vc+Vg(t).

[0049] Figure 4The following is a schematic diagram of the implementation process of the gating function of the photodetector in this embodiment. When the gating pulse generator is not triggered, the gating circuit does not output any electric pulses. At this time, Vc-V1=50V. Therefore, the electric field formed between the cathode and the first electrode of the electron multiplication system makes the cathode-emitted electrons fail to move in the direction from the cathode to the electron multiplication system, but move toward the cathode. The electrons fail to move to the MCP for electron multiplication and output. At this time, the entire detector is in an electronic cutoff state, as shown in a in the figure. After the gating pulse generator is triggered, the gating pulse generator generates a gating electric pulse signal and applies it to the cathode. The cathode voltage decreases as the amplitude of the gating electric pulse signal decreases. When the cathode voltage Vc+Vg(t)=V1, the cathode-emitted electrons have a certain emission kinetic energy, so the electrons will move from the cathode to the MCP for electron multiplication, so that the anode of the photodetector tube body outputs a detection signal of a certain amplitude, so that the photodetector has the function of detecting light signals. The photodetector also changes from the cutoff state to the gating state, realizing the gating function of the photodetector, as shown in b in the figure.

[0050] Figure 5 The schematic diagram of the variable gain process of the photodetector electron energy modulation in this embodiment is shown. After the photodetector gating function is realized, since the voltage difference between the cathode and the MCP incident electrode is small at this time, when the intensity of the detection light signal is high, although the cathode emits a large number of electrons, the energy of the emitted electrons incident on the MCP input surface is low, which makes the electron multiplication coefficient δ of the first electron multiplication in the MCP electron multiplication region 1 is less than 1. Although the working voltage value of the MCP group remains unchanged, the electron multiplication factor δ at the first electron multiplication 1 The MCP group is relatively small, so that the number of electrons in the electron multiplication region will not be too large during electron multiplication, which will cause serious space charge effect, and the MCP group is in the linear electron multiplication region. As the intensity of the detection light signal decreases, the amplitude Vg(t) of the gated electric pulse signal also decreases, so that the cathode real-time voltage value Vc+Vg(t) also decreases over time, and then the value of V1-(Vc+Vg(t)) increases, that is, the electron energy at the cathode where the electrons move to the MCP input surface also gradually increases from the initial kinetic energy, making the electron multiplication coefficient δ at the first electron multiplication 1 It also increases with the increase of electron energy, which increases the number of electrons in the first electron multiplication of the MCP electron multiplication zone. Although the light intensity becomes weaker, the number of electrons emitted by the cathode decreases, but due to the electron multiplication coefficient δ at the first electron multiplication 1 increases, while the operating voltage of the MCP group remains unchanged, making δ 2 *δ 3 …*δ n remains unchanged, so the overall electron gain of the MCP group electron multiplication system δ = δ1 *δ 2 *δ 3 …*δ n It shows an increasing trend, realizing the adjustment of high gain detection of weak light signal by MCP team, realizing the dynamic adjustment of photoelectric detection with low electronic gain when the light intensity is strong and dynamic increase of electronic gain when the light intensity becomes weak. When V1-(Vc+Vg(t))=200V, the gain of MCP reaches the maximum, and then the amplitude of the gated electric pulse signal increases with time. When the photocathode voltage is less than the voltage at the MCP input surface, the photodetector enters the cut-off state again.

[0051] Figure 6 This is the measurement change curve of the anode output pulse amplitude for different incident electron energies of the MCP type photomultiplier tube. During the test, the distance between the light source and the photomultiplier tube, the light source driving parameters, and the working voltage of the photomultiplier tube MCP are kept unchanged. The voltage value of the cathode is changed so that the difference between the MCP incident surface voltage and the cathode voltage increases from 0V to 200V. The anode output pulse is measured after each voltage change, the pulse amplitude is recorded, and a curve of the pulse amplitude changing with the difference between the MCP incident surface voltage and the cathode voltage is plotted. The experiment verifies the characteristics of different MCP gains corresponding to different electron incident energies.

[0052] To sum up, in the first embodiment of the photodetector described in the present invention, in the initial state, the cathode voltage is higher than the voltage at the MCP input surface, and the photodetector is in a cut-off state. When a strong light signal needs to be detected, the gating pulse generator is triggered to generate a gating electric pulse signal. After the gating electric pulse signal is applied to the cathode, the cathode voltage gradually decreases, thereby realizing the gating function of the photodetector. At the same time, as the amplitude of the gating electric pulse signal further decreases, the energy of the electrons emitted by the cathode gradually increases, so that the first and secondary electron multiplication factors of the MCP gradually increase, thereby increasing the electronic gain of the entire MCP group, and realizing dynamic adjustment of the photoelectric detection with low electronic gain when the light intensity is strong and the dynamic increase of electronic gain when the light intensity becomes weak, so that this device has a higher dynamic range.

Claims

1. A gated photoelectric detector with a large dynamic detection range, comprising a cathode (1), an electron multiplying system (2), an anode (3), a power supply system, a gated pulse generator and a pulse feeding circuit; the cathode (1), the electron multiplying system (2) and the anode (3) are arranged in sequence along the electron transmission direction and are located in a vacuum environment; the power supply system is connected to the cathode (1), the electron multiplying system (2) and the anode (3); the gated pulse generator is connected to the cathode (1) via the pulse feeding circuit; Features: The electron multiplication system (2) uses secondary electron multiplication material to multiply the electrons generated by the cathode (1); The gate pulse generator is used to generate a gate electrical pulse signal whose voltage amplitude decreases with time; the gate electrical pulse signal is a gate electrical pulse signal with a slow time parameter, ensuring that the time length required for detection is covered as much as possible; The pulse feeding circuit is used to feed the gated electrical pulse signal into the cathode (1), thereby realizing cathode (1) voltage modulation and cathode (1) emitted electron movement modulation to the energy of the electron multiplication system (2).

2. The gated photoelectric detector with large dynamic detection range according to claim 1, characterized in that: The waveform of the gate electrical pulse signal is a triangle wave, a sine wave or a cosine wave.

3. The gated photoelectric detector with large dynamic detection range according to claim 2, characterized in that: The electron multiplying system (2) is a microchannel plate electron multiplying system or a dynode electron multiplying system.

4. The gated photoelectric detector with large dynamic detection range according to claim 3, characterized in that: The cathode (1) is an ultraviolet cathode, an infrared cathode or a visible light cathode.

5. The gated photoelectric detector with large dynamic detection range according to claim 4, characterized in that: The anode (3) is a metal sheet anode or a conical anode.

6. The gated photoelectric detector with large dynamic detection range according to claim 5, characterized in that: The power supply system is a resistor voltage-dividing power supply system, a voltage-doubling power supply system or a transformer power supply system.

7. The gated photoelectric detector with a large dynamic detection range according to claim 6, characterized in that: The pulse feeding circuit is a separate electronic component or circuit system.

8. A control method for the gated photoelectric detector with a large dynamic detection range according to any one of claims 1 to 7, characterized in that: The following steps are involved: Step 1, the power supply system supplies power so that the cathode (1), the corresponding electrode of the electron multiplication system (2) and the anode (3) all have stable voltage values; Step 2: Adjust the power supply system so that the cathode (1) voltage is higher than the first electrode voltage of the electron multiplication system (2), and the voltage difference between the two is V c-d , the photodetector is in the cut-off state; Step 3: trigger the strobe pulse generator to generate a strobe electrical pulse signal whose voltage amplitude decreases with time, and the minimum amplitude of the strobe electrical pulse signal is V g , V g The value range is V c-d +10 to V c-d +400; When the cathode (1) voltage is equal to the first electrode voltage of the electron multiplying system (2), the photodetector changes from a cut-off state to a gating state, thus realizing a gating function; As the amplitude of the gate electric pulse signal further decreases, the energy of the electrons emitted by the cathode (1) gradually increases, causing the primary and secondary electron multiplication coefficients of the electron multiplication system (2) to gradually increase, thereby increasing the electron gain of the entire electron multiplication system (2).

Images