Photoelectric detection device

Abstract

The utility model discloses a photoelectric detection device, which comprises a shell, a light source inlet A and a light source inlet B are arranged on the shell, a photoelectric tube is arranged at the light source inlet A, and an infrared detection module is arranged at the light source inlet B. The shell is further internally provided with a power supply module, an infrared detection module and a photoelectric detection module, the power supply module is composed of an alternating current adapter, a voltage stabilizing integrated circuit and a plurality of rectifier diodes which are connected in series. The photoelectric tube is electrically connected with the digital display module and the sound-light alarm module respectively, and the infrared detection module is also electrically connected with the sound-light alarm module.

Description

Technical Field

[0001] This utility model relates to the field of photoelectric detection technology, and in particular to a photoelectric detection device. Background Technology

[0002] In the field of photoelectric detection, existing photoelectric effect instruments play an important role in experimental teaching and scientific research. However, they generally suffer from several technical problems that severely limit their application efficiency and accuracy. First, traditional photoelectric effect instruments typically require a long warm-up time before experiments. This process not only increases energy consumption but also significantly prolongs preparation time, thus reducing experimental efficiency. If the instrument is shut down and restarted during the experiment, it needs to be warmed up again. Second, the phototube and the electronically controlled detection equipment are independently packaged, requiring sequential connection and zeroing during operation. This makes the operation relatively complex, and improper operation can easily lead to significant deviations in experimental results, affecting the accuracy of the experiment.

[0003] Furthermore, while existing equipment offers high testing accuracy, this also makes the measurement system highly sensitive to ambient temperature. Experimental results are easily affected by changes in the external environment, such as temperature fluctuations and changes in light intensity, all of which can interfere with the results. A long waiting period is required for stabilization before measurements can begin. Moreover, traditional equipment typically uses pointer-type instruments for readings, which have low accuracy and are susceptible to parallax errors. This means that the observer may obtain different readings when viewing the pointer from different angles, directly affecting the accuracy of the measurement. Additionally, whether using pointer or digital instruments, manual range switching is required during measurement, followed by zeroing, affecting the continuity of the measurement. This delay can also lead to temperature drift, causing fluctuations in the measurement results. Furthermore, existing traditional instruments have limited functionality, a limited measurement range, and lack interactive audio-visual demonstrations. Summary of the Invention

[0004] In view of the above-mentioned prior art, the present invention provides a photoelectric detection device, which mainly solves the technical problems existing in the background art.

[0005] To achieve the above objectives, the technical solution of this utility model embodiment is implemented as follows:

[0006] A photoelectric detection device includes a housing with a light source inlet A and a light source inlet B. A phototube is installed at light source inlet A, and an infrared detection module is installed at light source inlet B. The housing also contains:

[0007] The power module consists of an AC adapter, a voltage regulator integrated circuit, and several rectifier diodes connected in series.

[0008] The digital display module and the audible and visual alarm module are provided. The phototube is electrically connected to the digital display module and the audible and visual alarm module respectively, and the infrared detection module is also electrically connected to the audible and visual alarm module.

[0009] Optionally, the electrical input terminal of the AC adapter is connected to an external AC power source, and its electrical output terminal is electrically connected in sequence to a voltage regulator integrated circuit and six rectifier diodes connected in series.

[0010] Optionally, the number of rectifier diodes is 6.

[0011] Optionally, the digital display module includes a digital voltmeter and a digital microammeter, wherein the digital microammeter is connected in series with the negative terminal of the phototube, and the digital voltmeter is connected in parallel between the positive terminal of the phototube and the ground wire.

[0012] Optionally, the audible and visual alarm module includes a preamplifier circuit with a first NPN transistor and an audible and visual alarm module. The base of the first NPN transistor is connected to the negative terminal of the phototube via switch K3, and its collector is connected to the audible and visual alarm module. The input terminal of the inverting amplifier circuit is connected to the signal output terminal of the infrared detection module, and the output terminal of the inverting amplifier circuit is connected to the audible and visual alarm module.

[0013] Optionally, the infrared detection module includes an infrared receiver tube and an inverting amplifier circuit with a second NPN transistor, wherein the signal output terminal of the infrared receiver tube is connected to the base of the second NPN transistor, and the collector of the second NPN transistor is connected to the audible and visual alarm module through switch k4.

[0014] Optionally, the housing is also provided with a voltage adjustment selection module consisting of switch K1, switch K2, switch K3, switch K4 and potentiometer to control the phototube operating voltage and the instrument operating mode.

[0015] The switch K1 is connected between the AC adapter and the voltage regulator integrated circuit;

[0016] The switch K2 has one selection terminal connected to the +20V input terminal of the voltage regulator integrated circuit, and the other selection terminal connected to the end of six rectifier diodes connected in series, with a potential of -4V. The output terminal is connected to the positive terminal of the phototube after being adjusted by the potentiometer.

[0017] The switch K3 is connected to the negative terminal of the phototube, and the two ends of the selected output are respectively connected to the base of the first NPN transistor and the input terminal of the digital microammeter.

[0018] The switch K4 is connected between the sound and light alarm input terminal and the collector of the second NPN transistor.

[0019] Optionally, the first NPN transistor is an NPN low-power 9014C transistor.

[0020] Optionally, the second NPN transistor is an 8050D transistor.

[0021] The beneficial effects of this invention are as follows: By combining the LM7805 voltage regulator circuit with multi-stage diodes to generate a +5V operating voltage and a -4V reverse voltage, the simplest positive and negative power supply system is achieved. Therefore, the additional voltage and temperature fluctuations are very small, achieving zero-warm-up start-up, effectively reducing standby power consumption, and significantly shortening standby time. The automatic range changing function of the digital display voltmeter and microammeter avoids the complicated operation of manual replacement and re-zeroing, improving work efficiency. The built-in structure of the phototube reduces the repeated manual wiring, disconnection, and zeroing operations, avoiding signal interference caused by excessively long leads or loose interfaces. The voltage resolution is improved to the 0.01V level, and the photocurrent detection sensitivity reaches the 10nA level, minimizing the parallax error and range switching interference of traditional pointer instruments. It also has an interactive demonstration function with sound and light alarms. The demonstration effect of its ultraviolet application function is vivid, making it suitable for university students to carry out science popularization teaching activities in primary and secondary schools in remote areas, and it can also be used as open design experimental equipment or demonstration instruments in higher education institutions. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the circuit structure of the photoelectric detection device in the embodiments of this application;

[0023] Figure 2 This is a graph showing the relationship between photocurrent and incident light flux in the embodiments of this application;

[0024] Figure 3 This is a graph showing the current-voltage characteristic curves in an embodiment of this application;

[0025] Figure 4 This is an overall schematic diagram of the photoelectric detection device in the embodiments of this application;

[0026] 1. Light source inlet B; 2. Four-pin infrared receiver module; 4. Light source inlet A; 5. Phototube; 7. AC input jack; 8. AC adapter; 9. Voltage regulator integrated circuit; 10. Audible and visual alarm module; 11. Rectifier diode; 13. Potentiometer; 15. Digital display microammeter; 16. Alarm indicator light; 17. Digital display voltmeter; 18. Housing. Detailed Implementation

[0027] The technical solution of this utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this utility model belongs. The terminology used in this specification of this utility model is for the purpose of describing particular embodiments only and is not intended to limit the utility model. In the following description, the expression "some embodiments" refers to a subset of all possible embodiments; however, it should be understood that "some embodiments" can be the same subset or different subsets of all possible embodiments and can be combined with each other without conflict.

[0028] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the present invention. However, it will be apparent to those skilled in the art that the present invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid confusion with the present invention.

[0029] It should be understood that this invention can be embodied in various forms and should not be construed as limited to the embodiments set forth herein. Rather, providing these embodiments will make the disclosure thorough and complete, and will fully convey the scope of this invention to those skilled in the art. Furthermore, the terminology used herein is intended only to describe particular embodiments and is not intended to limit the invention. When used herein, the singular forms “a,” “an,” and “the” are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the terms “compose” and / or “comprising,” when used in this specification, identify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups. When used herein, the term “and / or” includes any and all combinations of the associated listed items.

[0030] It should also be noted that when an element is referred to as being "fixed to" another element, it can be directly attached to the other element or there may be an intervening element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "inner," "outer," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0031] To fully understand this utility model, a detailed structure will be presented in the following description to illustrate the technical solution proposed by this utility model. Optional embodiments of this utility model are described in detail below; however, in addition to these detailed descriptions, this utility model may have other embodiments.

[0032] Please refer to the attached document. Figure 1 and Figure 4 This application provides a photoelectric detection device, which includes a housing 18. The housing 18 has a light source inlet A4 and a light source inlet B1. A phototube 5 is provided at the light source inlet A4, and an infrared detection module is provided at the light source inlet B1. The housing 18 also contains:

[0033] The power supply module consists of an AC adapter 8, a voltage regulator integrated circuit 9, and six rectifier diodes 11 connected in series, enabling multiple voltage outputs of +20V, +5V, and -4V.

[0034] The digital display module and the audible and visual alarm module 10 are included. The phototube 5 is electrically connected to the digital display module and the audible and visual alarm module 10, respectively. The infrared detection module is also electrically connected to the audible and visual alarm module 10.

[0035] Specifically, the photoelectric detection device provided in this application has a housing 18 made of white plastic, with overall dimensions of 220mm × 168mm × 80mm. The front of the housing 18 has a light source inlet A4 and a light source inlet B1. A quartz protective window, an ultraviolet filter, an infrared filter, or a monochromatic glass filter can be optionally installed at the light source inlet A4, secured by a plug-in slot. A phototube 5 is located directly behind the light source inlet A4, with its negative electrode facing the incident window. A power module consisting of an AC adapter 8, a voltage regulator integrated circuit 9, and multiple series-connected rectifier diodes 11 generates +5V, +20V, and a -4V reverse voltage required for reverse measurement. An external light source, after its wavelength is adjusted by the filter, is incident on the phototube 5. The photocurrent is displayed in real time by a digital display module. When the visible or ultraviolet photoelectric signal exceeds a threshold, the corresponding alarm is triggered. An infrared detection module is located directly behind the light source inlet B1. When the infrared detection module detects infrared light, and the output infrared electrical signal exceeds a threshold, the corresponding alarm is triggered.

[0036] In an optional embodiment, the electrical input terminal of the AC adapter 8 is connected to an external AC power source, and its electrical output terminal is electrically connected in sequence to a voltage regulator integrated circuit 9 and a plurality of rectifier diodes 11 connected in series, wherein the number of rectifier diodes 11 is 6.

[0037] Specifically, the input terminal of the AC adapter 8 is connected to a 220V / 50Hz AC power supply through the AC input socket 7, and the output terminal outputs a 24V DC voltage and is connected to the power module; the voltage regulator integrated circuit 9 is an LM7805 model, whose input terminal is directly connected to the 24V positive output terminal of the AC adapter 8, its ground terminal is connected to the common ground wire, and its output terminal provides a +5V stable voltage to power the digital instrument and logic circuit; the multiple series-connected rectifier diodes 11 are six 1N4001 type diodes connected end to end in sequence, with the first end of the diode group connected to the common ground wire at a potential of 0V, and the last end connected to the 24V negative output terminal of the AC adapter 8, outputting a -4V reverse voltage; the common ground wire is set between the 24V positive terminal and the last ends of the six diodes, forming a voltage regulation system with +20V as the reference; the total voltage drop of the six diodes is 4.2V, making the reverse voltage regulation range from -4V to 0V.

[0038] In an optional embodiment, the digital display module includes a digital voltmeter 17 and a digital microammeter 15. The digital microammeter 15 is connected in series with the negative terminal of the phototube 5, and the digital voltmeter 17 is connected in parallel between the positive terminal of the phototube 5 and the ground wire.

[0039] Specifically, the digital voltmeter 17 is a 5135B-DC30V model, with its positive lead soldered to the positive connection point of the phototube 5 and its negative lead directly connected to the common ground wire, displaying the working voltage value in the range of 0-30V in real time; the digital microammeter 15 is a 5135B-50μA model, with its positive terminal connected in series with the negative lead of the phototube 5 through a 1MΩ protective resistor, and its negative terminal soldered to the common ground wire, covering the range of 0-50μA photocurrent detection. When the phototube 5 is illuminated, it generates current, and the negative signal current enters the microammeter through the protective resistor to form a closed loop. The positive voltage value is directly read by the digital voltmeter 17, and the data of both are displayed synchronously on the LCD screen on the housing 18.

[0040] In an optional embodiment, the audible and visual alarm module 10 includes a preamplifier circuit with a first NPN transistor and the audible and visual alarm module 10. The first NPN transistor is an NPN low-power 9014C transistor. The base of the first NPN transistor is connected to the negative terminal of the phototube 5 through switch K3, and its collector is connected to the audible and visual alarm module 10. The input terminal of the inverting amplifier circuit is connected to the signal output terminal of the infrared detection module, and the output terminal of the inverting amplifier circuit is connected to the audible and visual alarm module 10.

[0041] In the preamplifier circuit of the sound and light alarm module 10, the first NPN transistor is a 9014C model. Its base is connected to the negative lead of the phototube 5 through the silver-plated contact of the K3 test-application switch. The base can be connected in series with a current-limiting resistor of a certain value and then in parallel with a 0.1μF ceramic capacitor to filter out high-frequency noise. The emitter of the first NPN transistor is connected to the signal input terminal of the sound and light alarm module 10, and its collector is connected in series with the +5V power line output by the LM7805 through a 2kΩ resistor. The sound and light alarm module 10 is used as the output to control the occurrence of the sound and light alarm. This circuit function is only applicable to the visible spectrum and ultraviolet spectrum. Because the infrared broadband will not produce a photoelectric effect in the vacuum phototube 5, a separate infrared detection module circuit needs to be added.

[0042] Furthermore, the infrared detection module includes a four-pin infrared receiving module 2 equipped with an infrared receiving tube and an inverting amplifier circuit with a second NPN transistor. The second NPN transistor is an 8050D transistor. The negative terminal of the four-pin infrared receiving module 2 is connected to a common ground wire, and the signal output terminal is connected to the base of the second NPN transistor. The collector of the second NPN transistor is connected to the audible and visual alarm module 10 through the on / off control of switch k2.

[0043] Specifically, the infrared receiving tube of the four-pin infrared receiving module 2 can be a PH302 type photodiode. Its signal output terminal is directly connected to the base of the second NPN transistor 8050D, and the positive terminal is connected to the +5V power supply line to form a bias circuit. The emitter of the second NPN transistor is connected to the common ground line, and the collector is connected to the signal input terminal of the sound and light alarm module 10 through the on / off control of the k2 switch. When the infrared receiving tube detects 940nm wavelength infrared light, the photocurrent is amplified by the inverting transistor 8050D, and its collector outputs a high-level signal to drive the sound and light alarm module 10 to trigger an alarm.

[0044] Furthermore, the audible and visual alarm module 10 consists of the alarm indicator light 16 and a buzzer.

[0045] In an optional embodiment, the housing 18 is further provided with a switch module consisting of switch K1, switch K2, switch K3, switch K4 and potentiometer 13. All switches are uniformly selected as KCD1-101 three-pin two-position rocker switches; potentiometer 13 is selected as a 22K precision ten-turn potentiometer.

[0046] The switch K1 is connected between the AC adapter 8 and the voltage regulator integrated circuit 9. It is the main power switch and controls the power supply of the entire system.

[0047] One selection terminal of switch K2 is connected to the +20V input terminal of the voltage regulator integrated circuit 9, and the other selection terminal is connected to the end of six series-connected rectifier diodes 11, with a potential of -4V. The output terminal is connected to the positive terminal of phototube 5 after voltage adjustment by the potentiometer 13. Switch K2 and 22K potentiometer 13 work together to determine the operating voltage range of phototube 5. For example, switch K2 selects the forward measurement voltage range of 0~20V or the reverse measurement voltage range of -4~0V. The 22K voltage adjustment potentiometer 13 is then adjusted to the required measurement value and applied to the positive terminal of phototube 5. The generated current flows through the negative terminal of phototube 5 and the protection resistor through the digital micro ammeter 15 to obtain the value of the test photocurrent.

[0048] The switch K3 is connected to the negative terminal of the phototube 5, and the two ends of the selected output are respectively connected to the base of the first NPN transistor and the input terminal of the digital display microammeter 15. The switch K3 is used to switch the signal path and distinguish between test and application functions. For example, when the switch K3 is switched from the measurement to the application selection position, the negative voltage signal of the phototube 5 will be sent to the base of the transistor 9014C in the preamplifier circuit to control the occurrence of the audible and visual alarm.

[0049] The switch K4 is connected between the audible and visual alarm input terminal and the collector of the second NPN transistor, and is used to independently control the activation of the infrared detection module.

[0050] The circuit principle of this utility model is as follows: The AC adapter 8 obtains a DC 24V power supply voltage, which is converted into a +5V voltage by the LM7805 voltage regulator integrated circuit 9 to power the digital instrument and other module circuits. The six 1N4001 rectifier diodes 11 obtain a voltage drop of about 4V to provide the -4V voltage required for reverse measurement of the photoelectric effect instrument. Since the ground wire is selected between 24V and -4V, the +24V power supply terminal provides a +20V working voltage for the instrument. The forward measurement voltage range of 0~20V or the reverse measurement voltage range of -4~0V is selected by the switch K2. The voltage adjustment potentiometer 13 is then adjusted to the required measurement value and applied to the positive terminal of the phototube 5. The generated current flows through the negative terminal of the phototube 5 and the protection resistor to the digital display micro ammeter 15 to obtain the value of the test photocurrent.

[0051] When switch K3 switches from measurement to application selection, the negative voltage signal of phototube 5 is sent to the base of transistor 9014C in the preamplifier circuit of the audible and visual alarm module 10, controlling the occurrence of the audible and visual alarm. This circuit function is only applicable to the visible and ultraviolet spectra. Because the infrared spectrum will not produce a photoelectric effect in the vacuum phototube 5, a separate infrared detection module circuit needs to be added. The infrared receiver tube detects the presence or absence of the infrared spectrum. The output signal is amplified by transistor 8050D and then output to the signal input terminal of the audible and visual alarm module 10 to trigger the infrared detection audible and visual alarm.

[0052] After the device was built, we tested the instrument's performance indicators and applications based on the three major laws of the photoelectric effect experiment.

[0053] 1. Change the distance between the light source and phototube 5 to adjust the luminous flux and measure the photocurrent.

[0054] Table 1. Relationship between photocurrent and incident luminous flux.

[0055]

[0056] Conclusion 1: From Figure 2 The curve showing the relationship between photocurrent and incident light flux indicates that, within the visible spectrum, the photocurrent increases with the increase of incident light flux, which verifies the first law of the photoelectric effect.

[0057] 2. Select monochromatic light sources of different wavelengths, read the wavelength values ​​using a handheld spectrometer, and then measure the current-voltage characteristic curves respectively. The results are as follows: Figure 3 As shown in Table 2.

[0058] Table 2. Measurement of phototube current-voltage characteristic curves

[0059]

[0060] 3. Select switch K2 for reverse measurement mode, determine the operating voltage range of phototube 5 as -4 to 0V, and use three or more monochromatic light sources to measure the reverse cutoff voltage of the photoelectric effect. The results are shown in Table 3, the experimental data table for measuring Planck's constant h. Substitute this data into Table 4, the curve slope fitting calculation table, to calculate the curve slope fitting value k. Multiply it by the fundamental charge of the electron e to obtain Planck's constant h. Compare it with the theoretical value of Planck's constant and calculate the absolute error and relative error.

[0061] Table 3. Experimental data for measuring Planck's constant h

[0062]

[0063] Substitute the data into Table 4, the linear fitting calculation table for the curve slope, to obtain the value of the slope K.

[0064] Table 4. Curve Slope Fitting Calculation Table

[0065]

[0066] Calculate Planck's constant: Elementary charge of electron e = 1.602 × 10⁻⁶ -19 C;

[0067] h = e·K = 1.602 × 10 -19 ×0.3853×10-14 =6.17×10 -34 J.S

[0068] Theoretical value of Planck's constant:

[0069] h 理 =6.626×10 -34 J.S

[0070] Absolute error:

[0071] △h=h 理 -h = (6.626 - 6.17) × 10 -34 =0.5×10 -34 J.S

[0072] Relative error:

[0073] E(h)=△h / h 理 ×100% = 8%

[0074] Result expression:

[0075] h = (6.2 ± 0.5) × 10 -34 J.S

[0076] Conclusion 3: The accuracy of Planck's constant measurement results can verify the third law of the photoelectric effect.

[0077] 4. Select the instrument's operating mode as the audible and visual alarm detection application state using switch K3, and conduct tests using different types of light sources and blocking materials. The results are shown in the table below.

[0078] Table 5: Application Test of Extended Functions of the Photoelectric Effect Broad-Spectrum Experiment Instrument

[0079]

[0080]

[0081] Conclusion 4. When used for detection in the ultraviolet spectrum, phototube 5 can effectively resist interference from visible light, has a very wide detection angle, and responds quickly and sensitively. It has strong application prospects in fire alarm and fire source tracking. Although it has some detection functions in the visible light and infrared spectrum regions, it is often replaced by semiconductor optoelectronic devices due to its large size and high cost.

[0082] The above are merely specific embodiments of this utility model, but the protection scope of this utility model is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in this utility model should be included within the protection scope of this utility model. The protection scope of this utility model should be determined by the protection scope of the stated claims.

Claims

1. A photoelectric detection device, the detection device comprising a housing, wherein the housing is provided with a light source inlet A and a light source inlet B, characterized in that, A phototube is installed at the light source inlet A, an infrared detection module is installed at the light source inlet B, and the following is also provided inside the housing: The power module consists of an AC adapter, a voltage regulator integrated circuit, and several rectifier diodes connected in series. The digital display module and the audible and visual alarm module are provided. The phototube is electrically connected to the digital display module and the audible and visual alarm module respectively, and the infrared detection module is also electrically connected to the audible and visual alarm module.

2. The photoelectric detection device according to claim 1, characterized in that, The AC adapter's input terminal is connected to an external AC power source, and its output terminal is electrically connected in sequence to a voltage regulator integrated circuit and multiple rectifier diodes connected in series.

3. The photoelectric detection device according to claim 2, characterized in that, The number of rectifier diodes is 6.

4. The photoelectric detection device according to claim 1, characterized in that, The digital display module includes a digital voltmeter and a digital microammeter. The digital microammeter is connected in series with the negative terminal of the phototube, and the digital voltmeter is connected in parallel between the positive terminal of the phototube and the ground wire.

5. The photoelectric detection device according to claim 2, characterized in that, The sound and light alarm module includes a preamplifier circuit with a first NPN transistor and a sound and light alarm module. The base of the first NPN transistor is connected to the negative terminal of the phototube through switch K3, and its collector is connected to the sound and light alarm module.

6. The photoelectric detection device according to claim 5, characterized in that, The infrared detection module includes an infrared receiver tube and an inverting amplifier circuit with a second NPN transistor. The signal output terminal of the infrared receiver tube is connected to the base of the second NPN transistor, and the collector of the second NPN transistor is connected to the audible and visual alarm module through switch k4.

7. The photoelectric detection device according to claim 6, characterized in that, The housing is also equipped with a voltage adjustment and selection module consisting of switches K1, K2, K3, K4, and a potentiometer to control the working voltage of the phototube and the working mode of the instrument. The switch K1 is connected between the AC adapter and the voltage regulator integrated circuit; One selection terminal of the switch K2 is connected to the input terminal of the +20V voltage regulator integrated circuit, and the other selection terminal is connected to the end of six rectifier diodes connected in series, with a potential of -4V. The output terminal is connected to the positive terminal of the phototube after being adjusted by the potentiometer. The switch K3 is connected to the negative terminal of the phototube, and the two ends of the selected output are respectively connected to the base of the first NPN transistor and the input terminal of the digital microammeter. The switch K4 is connected between the sound and light alarm input terminal and the collector of the second NPN transistor.

8. The photoelectric detection device according to claim 7, characterized in that, The first NPN transistor is an NPN low-power 9014C transistor.

9. The photoelectric detection device according to claim 6, characterized in that, The second NPN transistor is an 8050D transistor.

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