CN115835445B

CN115835445B - Lighting electric control system of microscopic imaging device

Info

Publication number: CN115835445B
Application number: CN202211539483.3A
Authority: CN
Inventors: 王华峰; 张新; 贾银川; 金磊; 张亚龙
Original assignee: Jiaxing Zhitong Technology Co ltd
Current assignee: Jiaxing Zhitong Technology Co ltd
Priority date: 2022-12-02
Filing date: 2022-12-02
Publication date: 2023-06-06
Anticipated expiration: 2042-12-02
Also published as: CN115835445A

Abstract

The invention discloses an illumination electric control system of a microscopic imaging device, which comprises an input terminal CN1, a control switch SW1, a power supply filter circuit, a secondary electronic control switch circuit, a power supply conversion module, a pulse modulation direct current circuit and an output interface which are sequentially connected, wherein the power supply conversion module is provided with a power supply abnormality correction module. The LED light source provided by the invention not only can provide working current of the LED light source under different brightness working conditions, but also can correct abnormal output conditions of the power supply, and meanwhile, the brightness of the light source is stable.

Description

Lighting electric control system of microscopic imaging device

Technical Field

The invention relates to an illumination electric control system of a microscopic imaging device, which is used for improving the function of a surgical microscope and enabling the surgical microscope to be humanized, automatic, digital and intelligent.

Background

Optical microscopy is a treatment device which is stock in many departments in modern hospitals. Such as ophthalmic, neurosurgical, otorhinolaryngological, orthopedic, and the like, departments often employ optical microscopy to treat disease in a patient. The light source which is an important component of the optical microscope provides a guarantee for illumination of the operation process.

It can be seen that xenon lamp illumination systems are used in some of the early microscope products of foreign companies, such as lycra and zeiss, which specialized production microscopes, but the illumination systems have the problem of short service life (the service life of each xenon lamp bulb is only about 1500 hours) and mostly being mechanically adjustable, so that it is difficult to meet the development requirements of the optical imaging technology of the day-to-day variation. The LED is used as a new light source, the power of a single chip is continuously improved along with the continuous improvement of a manufacturing process, the LED with more than 100W is already on the market, the LED light source has the characteristics of long service life (the service life can reach 6-10 ten thousand hours and is more than 10 times of that of the traditional light source), flexible and rapid light modulation, simple light condensation scheme and the like, can well replace the existing illumination system, and provides convenience for surgical scenes such as surgical microscopic imaging, fluorescent imaging and the like.

Disclosure of Invention

The invention aims to: in order to overcome the defects in the prior art, the invention provides an illumination electric control system of a microscopic imaging device.

The technical scheme is as follows: in order to achieve the above purpose, the invention adopts the following technical scheme:

the utility model provides a microscopic imaging device's illumination electrical system, includes input terminal CN1, control switch SW1, power filter circuit, second grade electronic control switch circuit, power conversion module, pulse modulation direct current circuit and the output interface that connects gradually, be provided with the power anomaly correction module on the power conversion module.

Preferably: the power supply filter circuit comprises a capacitor C1, an inductor L2, a capacitor C2 and a capacitor C3, wherein the control switch SW1 is arranged at the positive end of the input terminal CN1, one end of the capacitor C1 is connected with the negative end of the input terminal CN1, and the other end of the capacitor C1 is connected with the control switch SW 1; one end of the inductor L1 is connected with the control switch SW1, and one end of the inductor L2 is connected with the negative end of the input terminal CN 1; one end of the capacitor C2 is connected with the other end of the inductor L1, and the other end of the capacitor C2 is connected with the other end of the inductor L2; the capacitor C3 is connected in parallel with the capacitor C2.

Preferably: the secondary electronic control switch circuit comprises a limit switch SW2, a resistor R6, a resistor R7, a capacitor C5, a triode Q2, a triode Q3, a capacitor C6 and a zener diode D9, wherein the resistor R6 and the capacitor C5 are connected in series and then connected in parallel at two ends of the capacitor C3; one end of the resistor R7 is connected with the other end of the inductor L1, the other end of the resistor R7 is connected with the collector electrode of the triode Q3, the emitting electrode of the triode Q3 is grounded, and a lead wire connected in series with the resistor R6 and the capacitor C5 is connected with the base electrode of the triode Q3; one end of the limit switch SW2 is connected with the base electrode of the triode Q3, and the other end of the limit switch SW2 is grounded; the emitter of the triode Q2 is connected with the other end of the inductor L1, the base electrode of the triode Q2 is connected with the collector electrode of the triode Q2, and the collector electrode of the triode Q2 is connected with the VCC-MOS interface; one end of the capacitor C6 is connected with the collector electrode of the triode Q2, the other end of the capacitor C6 is grounded, and the zener diode D9 is connected in parallel with the two ends of the capacitor C6.

Preferably: the power conversion module comprises a buck conversion chip U2, the pulse modulation direct current circuit comprises an inductor L3, a capacitor C17, a capacitor C18, a capacitor C19, a resistor R12, a capacitor zero C20, a dummy load resistor R13, a capacitor C21, an inductor L4 and an inductor L5, the positive poles of an output pin SW, the inductor L3, the inductor L4 and an output interface CN4 of the buck conversion chip U2 are sequentially connected, one end of the capacitor C17 is connected with a connecting wire between the inductor L3 and the inductor L4, the other end of the capacitor C17 is grounded, and the capacitor C18, the capacitor C19 and the dummy load resistor R13 are all connected with two ends of the capacitor C17 in parallel; one end of the resistor R12 is grounded, and the other end of the resistor R12, the inductor L5 and the negative electrode of the output interface CN4 are sequentially connected; the capacitor zero C20 is connected in parallel with the two ends of the resistor R12; one end of the capacitor C21 is connected to a connection wire between the inductor L3 and the inductor L4, and the other end of the capacitor C21 is connected to a connection wire between the other end of the resistor R12 and the inductor L5.

Preferably: the power supply abnormality correction module comprises a resistor R2, a triode Q1, a resistor R4, a light-emitting diode D3, a light-emitting diode D4, a light-emitting diode D5, a resistor R3, an operational amplifier U3, a resistor R15, a resistor R14 and a capacitor C26, wherein a collector of the triode Q1 is connected with a pin EN of a buck conversion chip U2, and a base of the triode Q1, the light-emitting diode D3, the light-emitting diode D4, the light-emitting diode D5 and an LED positive electrode interface are sequentially connected; one end of the resistor R4 is connected with the base electrode of the triode Q1, the other end of the resistor R4 is connected with the VCS interface, and the emitter electrode of the triode Q1 is grounded; one end of the resistor R3 is connected with the base electrode of the triode Q1, and the other end of the resistor R3 is connected with the first non-inverting input end +INA of the operational amplifier U3; the reverse input end of the No. 2 pin of the operational amplifier U3 is grounded through a resistor R15, one end of a resistor R14 is connected with the first reverse input end-INA of the operational amplifier U3, the other end of the resistor R14 is connected with the first output end OUTA of the operational amplifier U3, and a capacitor C26 is connected in parallel with the two ends of the resistor R14.

Preferably: the power supply abnormality correction module is provided with a brightness adjustment circuit, the brightness adjustment circuit comprises a resistor R16, a resistor R17, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a resistor R22, a capacitor C27 and an adjustable potentiometer R23, a second inverting input end-INB of the operational amplifier U3, the resistor R19, the resistor R20, the resistor R21, the resistor R22 and a VCC-3.0V interface are sequentially connected, a second output end OUTB of the operational amplifier U3 is connected with the interface U3-7, one end of the resistor R18 is connected with a second output end OUTB of the operational amplifier U3, and the other end of the resistor R18 is connected with a second inverting input end-INB of the operational amplifier U3; one end of the resistor R16 is connected with the second non-inverting input end +INB of the operational amplifier U3, and the other end of the resistor R is grounded; one end of a resistor R17 is connected with a second non-inverting input end +INB of the operational amplifier U3, and the other end of the resistor R is connected with a VCC-3.0V interface; the fixed contact I of the adjustable potentiometer R23 is grounded, a connecting wire between the resistor R19 and the resistor R20 is connected with the movable contact II of the adjustable potentiometer R23, and a connecting wire between the resistor R20 and the resistor R21 is connected with the fixed contact III of the adjustable potentiometer R23; one end of the capacitor C27 is grounded, and the resistor R22 and the VCC-3.0V interface connecting wire are connected with the other end of the capacitor C27.

Preferably: the power supply indicating circuit comprises a resistor R5 and a light emitting diode D2, wherein the resistor R5 and the light emitting diode D2 are connected in series and then connected in parallel at two ends of a capacitor C3.

Preferably: the pin SS of the buck conversion chip U2 is grounded through a capacitor C10, and the pin VREG of the buck conversion chip U2 is grounded through a capacitor C9; the pin VBST of the buck conversion chip U2 is connected with the pin GND of the buck conversion chip U2 in the chip through a diode; outside the chip, the pin VBST of the buck conversion chip U2 is connected with the pin SW of the buck conversion chip U2 through the ceramic chip capacitor C11.

Preferably: the buck converter chip U2 is an 18V input 6A synchronous buck converter.

Compared with the prior art, the invention has the following beneficial effects:

the LED light source provided by the invention is provided with the power supply filter circuit, the secondary electronic control switch circuit, the power supply conversion module, the pulse modulation direct current circuit and the power supply abnormality correction module, so that the LED light source can not only provide working currents of the LED light source under different brightness working conditions, but also correct abnormal output conditions of the power supply, and meanwhile, the brightness of the light source is stable. .

Drawings

Fig. 1 is a schematic diagram of an upper layer circuit according to an embodiment of the invention.

Fig. 2 is a schematic diagram of a two-stage electronically controlled switch circuit.

Fig. 3 is a schematic diagram of a lower layer circuit according to an embodiment of the invention.

Fig. 4 is a schematic diagram of a pulse modulated dc circuit.

Fig. 5 is a schematic diagram of a power abnormality correction module.

Fig. 6 is a schematic diagram of a brightness adjusting circuit.

Detailed Description

The present invention is further illustrated in the accompanying drawings and detailed description which are to be understood as being merely illustrative of the invention and not limiting of its scope, and various equivalent modifications to the invention will fall within the scope of the appended claims to the skilled person after reading the invention.

An illumination electric control system of a microscopic imaging device mainly realizes the functions of switching a light source, adjusting brightness, switching the light source and the like. The LED lamp has the beneficial effects of convenience in light source control, stable light source brightness and the like. As shown in fig. 1 and 3, the device comprises an input terminal CN1, a control switch SW1, a power supply filter circuit, a secondary electronic control switch circuit, a power supply conversion module, a pulse modulation direct current circuit and an output interface which are sequentially connected, wherein the input terminal CN1 is an external 12VDC direct current input interface, and the interface is electrically connected and input by adopting an aviation head or a connector with a self-locking function. The control switch SW1 is used for controlling the on-off of the power supply and realizing the on-off control of the light source. In the case where the control switch SW1 is turned off, the illumination light source is turned off; when the control switch SW1 is turned on, the illumination light source is turned on. The power supply conversion module is provided with a power supply abnormality correction module.

As shown in fig. 1, the power supply filter circuit includes a capacitor C1, an inductor L2, a capacitor C2, and a capacitor C3, where the power supply filter circuit is configured to filter external interference to ensure stability of a power supply. The control switch SW1 is arranged at the positive end of the input terminal CN1, one end of the capacitor C1 is connected to the negative end of the input terminal CN1, and the other end of the capacitor C1 is connected to the control switch SW 1; one end of the inductor L1 is connected with the control switch SW1, and one end of the inductor L2 is connected with the negative end of the input terminal CN 1; one end of the capacitor C2 is connected with the other end of the inductor L1, and the other end of the capacitor C2 is connected with the other end of the inductor L2; the capacitor C3 is connected in parallel with the capacitor C2.

As shown in fig. 2, the secondary electronic control switch circuit includes a limit switch SW2, a resistor R6, a resistor R7, a capacitor C5, a triode Q2, a triode Q3, a capacitor C6, and a zener diode D9, where the resistor R6 and the capacitor C5 are connected in series and then connected in parallel to two ends of the capacitor C3; one end of the resistor R7 is connected with the other end of the inductor L1, the other end of the resistor R7 is connected with the collector electrode of the triode Q3, the emitting electrode of the triode Q3 is grounded, and a lead wire connected in series with the resistor R6 and the capacitor C5 is connected with the base electrode of the triode Q3; one end of the limit switch SW2 is connected with the base electrode of the triode Q3, and the other end of the limit switch SW2 is grounded; the emitter of the triode Q2 is connected with the other end of the inductor L1, the base electrode of the triode Q2 is connected with the collector electrode of the triode Q2, and the collector electrode of the triode Q2 is connected with the VCC-MOS interface; one end of the capacitor C6 is connected with the collector electrode of the triode Q2, the other end of the capacitor C6 is grounded, and the zener diode D9 is connected in parallel with the two ends of the capacitor C6. The limit switch SW2 represents a limit switch and is arranged on a horizontal cantilever of the microscope, the horizontal cantilever can swing up and down, when the cantilever swings to an upper limit position, the limit switch SW2 is closed, the triode Q3 element is converted from an on state to an off state, and the triode Q2 is also converted from the on state to the off state, so that the 12VDC power supply is controlled to be disconnected, the 12VDC input of the lighting circuit is cut off, and the lighting is turned off.

As shown in fig. 3, the power conversion module includes a buck conversion chip U2, and the power conversion circuit using the buck conversion chip U2 as a core implements V/I conversion, and provides working currents of the LED light source under different brightness working conditions. In order to ensure the stable and reliable operation of the circuit, the circuit is also provided with auxiliary circuits such as an overvoltage protection circuit, an overcurrent protection circuit, a cooling fan power supply circuit and the like.

The buck conversion chip U2 is an 18V input 6A synchronous buck converter, supports quick transient response, and has the characteristics of wide input voltage and low output ripple. And the high-efficiency integrated field effect transistor built in the U2 is optimized for low duty ratio application, so that the current consumption is low when the power supply is turned off, and the power supply efficiency is improved. The pre-bias soft start is built in the buck conversion chip U2, the soft start time is adjustable, the instantaneous impact current is effectively limited, and the electric stress born by the input capacitor is reduced.

The pin SS of the buck conversion chip U2 is grounded through a capacitor C10, and the pin VREG of the buck conversion chip U2 is grounded through a capacitor C9; the pin VBST of the buck conversion chip U2 is connected with the pin GND of the buck conversion chip U2 in the chip through a diode; outside the chip, the pin VBST of the buck conversion chip U2 is connected with the pin SW of the buck conversion chip U2 through the ceramic chip capacitor C11.

The 12VDC power is filtered and stabilized by a series of capacitors and then is input into the 8 pin (power input pin VIN) and the 5 pin (power input pin GND) of the buck conversion chip U2, after the chip is normally powered, the 1 pin (work enabling pin EN) of the buck conversion chip U2 is in an effective high level, the chip is allowed to normally work, if the chip is in a just-started state, the 4 pin (soft start control pin SS) of the U2 is connected with the soft start capacitor C10 to be charged, the soft start circuit starts to work, and the soft start circuit is always accompanied and regulated in the process that the voltage of the output end reaches the normal working voltage until the soft start time is finished.

The 7 pins (the power supply pins VBST of the upper driving tube driving circuit) of the buck conversion chip U2 are connected with the 5 pins of the buck conversion chip U2 in the chip through a diode, and the 7 pins and the 6 pins outside the chip are connected through a ceramic chip capacitor C11, so that bootstrap power supply is realized for the upper driving tube driving power supply, normal conduction of the upper driving tube is ensured, and normal operation of the whole circuit is ensured.

When the input voltage is too low, the chip will enter an under-voltage protection mode, and the chip will close the output and stop working at this time, and the under-voltage protection mode will not jump out again until the input voltage is recovered to be normal, and the normal working is resumed. The voltage is led out to the 3 pin (5.5V power output pin) of the buck converter U2, and a filter capacitor C9 is typically connected to the 3 pin of the buck converter U2. The voltage is turned off when the enable signal of the chip is low.

As shown in fig. 4, the pulse modulation dc circuit includes an inductor L3, a capacitor C17, a capacitor C18, a capacitor C19, a resistor R12, a capacitor zero C20, a dummy load resistor R13, a capacitor C21, an inductor L4, and an inductor L5, wherein the output pin SW of the buck conversion chip U2, the inductor L3, the inductor L4, and the positive electrode of the output interface CN4 are sequentially connected, one end of the capacitor C17 is connected with a connecting wire between the inductor L3 and the inductor L4, and the other end of the capacitor C17 is grounded, and the capacitor C18, the capacitor C19, and the dummy load resistor R13 are all connected in parallel with two ends of the capacitor C17; one end of the resistor R12 is grounded, and the other end of the resistor R12, the inductor L5 and the negative electrode of the output interface CN4 are sequentially connected; the capacitor zero C20 is connected in parallel with the two ends of the resistor R12; one end of the capacitor C21 is connected to a connection wire between the inductor L3 and the inductor L4, and the other end of the capacitor C21 is connected to a connection wire between the other end of the resistor R12 and the inductor L5.

The 6 pin (the upper and lower switch tube output pin SW) of the buck conversion chip U2 is used for connecting the output inductor L3 with the output capacitors C17, C18, C19 and the dummy load R13, which are key nodes of the whole conversion circuit. The switching frequency of pin SW is 650kHz when operating normally. The series of pulse width modulated signals are filtered by the inductor and the capacitor to generate direct current with certain ripple, and the direct current flows through the LED light source through the output interface CN 4.

As shown in fig. 5, the power abnormality correction module includes a resistor R2, a triode Q1, a resistor R4, a light emitting diode D3, a light emitting diode D4, a light emitting diode D5, a resistor R3, an operational amplifier U3, a resistor R15, a resistor R14, and a capacitor C26, wherein a collector of the triode Q1 is connected with a pin EN of the buck conversion chip U2, and a base of the triode Q1, the light emitting diode D3, the light emitting diode D4, the light emitting diode D5, and an LED positive interface are sequentially connected; one end of the resistor R4 is connected with the base electrode of the triode Q1, the other end of the resistor R4 is connected with the VCS interface, and the emitter electrode of the triode Q1 is grounded; one end of the resistor R3 is connected with the base electrode of the triode Q1, and the other end of the resistor R3 is connected with the first non-inverting input end +INA of the operational amplifier U3; the reverse input end of the No. 2 pin of the operational amplifier U3 is grounded through a resistor R15, one end of a resistor R14 is connected with the first reverse input end-INA of the operational amplifier U3, the other end of the resistor R14 is connected with the first output end OUTA of the operational amplifier U3, and a capacitor C26 is connected in parallel with the two ends of the resistor R14.

The 2 pin (feedback input pin VFB) of the buck conversion chip U2 is configured to receive a feedback signal from the power supply, including an output voltage detection, an output current detection, and a potentiometer feedback signal indicative of the brightness adjustment of the light source. The output voltage of the power supply is converted into voltage through three diodes D3, D4 and D5 and the output current of the power supply through a sampling resistor R12 and fed back to the first in-phase input end +INA of the operational amplifier U3 together through a resistor R4, the first reverse input end-INA of the operational amplifier U3 is grounded through a resistor R15, and is connected to the first output end OUTA of the operational amplifier U3 through a resistor R14 and a capacitor C26 which are connected in parallel, and the output signal is connected to the 2 pin of the operational amplifier U2 through a resistor R8 and a capacitor C7 which are connected in parallel. When the output voltage of the power supply is too high or the abnormal condition that the output current flows over occurs, the abnormal signals are fed back to the 2 pin after being collected, and the operational amplifier U2 corrects the abnormal output condition of the power supply by adjusting the duty ratio of PWM and other modes, so that the normal output of the power supply is ensured.

In order to realize the brightness adjustment of the light source, the power supply abnormality correction module is provided with a brightness adjustment circuit, and the single-way of the invention adopts an implementation mode of an adjustable potentiometer. As shown in fig. 6, the brightness adjusting circuit includes a resistor R16, a resistor R17, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a resistor R22, a capacitor C27, and an adjustable potentiometer R23, where the second inverting input terminal-INB of the operational amplifier U3, the resistor R19, the resistor R20, the resistor R21, the resistor R22, and the VCC-3.0V interface are sequentially connected, the second output terminal OUTB of the operational amplifier U3 is connected with the interface of U3-7, one end of the resistor R18 is connected with the second output terminal OUTB of the operational amplifier U3, and the other end is connected with the second inverting input terminal-INB of the operational amplifier U3; one end of the resistor R16 is connected with the second non-inverting input end +INB of the operational amplifier U3, and the other end of the resistor R is grounded; one end of a resistor R17 is connected with a second non-inverting input end +INB of the operational amplifier U3, and the other end of the resistor R is connected with a VCC-3.0V interface; the fixed contact I of the adjustable potentiometer R23 is grounded, a connecting wire between the resistor R19 and the resistor R20 is connected with the movable contact II of the adjustable potentiometer R23, and a connecting wire between the resistor R20 and the resistor R21 is connected with the fixed contact III of the adjustable potentiometer R23; one end of the capacitor C27 is grounded, and the resistor R22 and the VCC-3.0V interface connecting wire are connected with the other end of the capacitor C27. The resistors R19, R20, R21, R22 and R23 (adjustable potentiometers) form an input network and are connected to the inverting input end of the pin 6 of the U3, the voltage dividing network formed by the resistors R16 and R17 is connected to the non-inverting input end of the pin 5 of the U3, the feedback resistor R18 is bridged between the pin 6 and the pin 7, and the second output end OUTB of the operational amplifier U3 is connected to the pin 2 of the operational amplifier U2 through the resistor R9. The voltage value of the No. 2 pin VFB of the impedance adjustable operational amplifier U2 connected to the network is changed by adjusting the adjustable potentiometer R23, so that the output current value of the power supply is changed, and the aim of adjusting the brightness of the light source is fulfilled.

As shown in fig. 1, includes a power indication circuit for power indication. The power supply indication circuit comprises a resistor R5 and a light emitting diode D2, wherein the resistor R5 and the light emitting diode D2 are connected in series and then connected in parallel at two ends of a capacitor C3.

In another embodiment of the invention, in order to ensure the reliability of illumination, 2 sets of light sources with identical circuits are adopted, one set is used normally and the other set is used for standby. The switching of the light source is realized through the design structure.

The foregoing is only a preferred embodiment of the invention, it being noted that: it will be apparent to those skilled in the art that various modifications and adaptations can be made without departing from the principles of the present invention, and such modifications and adaptations are intended to be comprehended within the scope of the invention.

Claims

1. An illumination electric control system of a microscopic imaging device is characterized in that: the power supply abnormality correction device comprises an input terminal CN1, a control switch SW1, a power supply filter circuit, a secondary electronic control switch circuit, a power supply conversion module, a pulse modulation direct current circuit and an output interface which are sequentially connected, wherein the power supply conversion module is provided with a power supply abnormality correction module;

the power supply abnormality correction module comprises a resistor R2, a triode Q1, a resistor R4, a light-emitting diode D3, a light-emitting diode D4, a light-emitting diode D5, a resistor R3, an operational amplifier U3, a resistor R15, a resistor R14 and a capacitor C26, wherein a collector of the triode Q1 is connected with a pin EN of a buck conversion chip U2, an emitter of the triode Q1 is grounded, and a base of the triode Q1, the light-emitting diode D3, the light-emitting diode D4, the light-emitting diode D5 and an LED positive interface are sequentially connected; one end of the resistor R4 is connected with the base electrode of the triode Q1, and the other end of the resistor R is connected with the VCS interface; one end of the resistor R3 is connected with the base electrode of the triode Q1, and the other end of the resistor R3 is connected with the first non-inverting input end +INA of the operational amplifier U3; the first reverse input end-INA of the operational amplifier U3 is grounded through a resistor R15, one end of a resistor R14 is connected with the first reverse input end-INA of the operational amplifier U3, the other end of the resistor R14 is connected with the first output end OUTA of the operational amplifier U3, and a capacitor C26 is connected in parallel with the two ends of the resistor R14;

the power supply abnormality correction module is provided with a brightness adjustment circuit, the brightness adjustment circuit comprises a resistor R16, a resistor R17, a resistor R18, a resistor R19, a resistor R20, a resistor R21, a resistor R22, a capacitor C27 and an adjustable potentiometer R23, a second inverting input end-INB of the operational amplifier U3, the resistor R19, the resistor R20, the resistor R21, the resistor R22 and a VCC-3.0V interface are sequentially connected, a second output end OUTB of the operational amplifier U3 is connected with the interface U3-7, one end of the resistor R18 is connected with a second output end OUTB of the operational amplifier U3, and the other end of the resistor R18 is connected with a second inverting input end-INB of the operational amplifier U3; one end of the resistor R16 is connected with the second non-inverting input end +INB of the operational amplifier U3, and the other end of the resistor R is grounded; one end of a resistor R17 is connected with a second non-inverting input end +INB of the operational amplifier U3, and the other end of the resistor R is connected with a VCC-3.0V interface; the fixed contact I of the adjustable potentiometer R23 is grounded, a connecting wire between the resistor R19 and the resistor R20 is connected with the movable contact II of the adjustable potentiometer R23, and a connecting wire between the resistor R20 and the resistor R21 is connected with the fixed contact III of the adjustable potentiometer R23; one end of the capacitor C27 is grounded, and the resistor R22 and the VCC-3.0V interface connecting wire are connected with the other end of the capacitor C27.

2. The illumination electronic control system of the microscopic imaging device according to claim 1, wherein: the power supply filter circuit comprises a capacitor C1, an inductor L2, a capacitor C2 and a capacitor C3, wherein the control switch SW1 is arranged at the positive end of the input terminal CN1, one end of the capacitor C1 is connected with the negative end of the input terminal CN1, and the other end of the capacitor C1 is connected with the control switch SW 1; one end of the inductor L1 is connected with the control switch SW1, and one end of the inductor L2 is connected with the negative end of the input terminal CN 1; one end of the capacitor C2 is connected with the other end of the inductor L1, and the other end of the capacitor C2 is connected with the other end of the inductor L2; the capacitor C3 is connected in parallel with the capacitor C2.

3. The illumination electronic control system of the microscopic imaging device according to claim 2, wherein: the secondary electronic control switch circuit comprises a limit switch SW2, a resistor R6, a resistor R7, a capacitor C5, a triode Q2, a triode Q3, a capacitor C6 and a zener diode D9, wherein the resistor R6 and the capacitor C5 are connected in series and then connected in parallel at two ends of the capacitor C3; one end of the resistor R7 is connected with the other end of the inductor L1, the other end of the resistor R7 is connected with the collector electrode of the triode Q3, the emitting electrode of the triode Q3 is grounded, and a lead wire connected in series with the resistor R6 and the capacitor C5 is connected with the base electrode of the triode Q3; one end of the limit switch SW2 is connected with the base electrode of the triode Q3, and the other end of the limit switch SW2 is grounded; the emitter of the triode Q2 is connected with the other end of the inductor L1, the base electrode of the triode Q2 is connected with the collector electrode of the triode Q2, and the collector electrode of the triode Q2 is connected with the VCC-MOS interface; one end of the capacitor C6 is connected with the collector electrode of the triode Q2, the other end of the capacitor C6 is grounded, and the zener diode D9 is connected in parallel with the two ends of the capacitor C6.

4. A lighting electrical control system for a microscopic imaging device according to claim 3, wherein: the power conversion module comprises a buck conversion chip U2, the pulse modulation direct current circuit comprises an inductor L3, a capacitor C17, a capacitor C18, a capacitor C19, a resistor R12, a capacitor C20, a dummy load resistor R13, a capacitor C21, an inductor L4 and an inductor L5, the positive poles of an output pin SW, the inductor L3, the inductor L4 and an output interface CN4 of the buck conversion chip U2 are sequentially connected, one end of the capacitor C17 is connected with a connecting wire between the inductor L3 and the inductor L4, the other end of the capacitor C17 is grounded, and the capacitor C18, the capacitor C19 and the dummy load resistor R13 are all connected with two ends of the capacitor C17 in parallel; one end of the resistor R12 is grounded, and the other end of the resistor R12, the inductor L5 and the negative electrode of the output interface CN4 are sequentially connected; the capacitor C20 is connected in parallel with two ends of the resistor R12; one end of the capacitor C21 is connected to a connection wire between the inductor L3 and the inductor L4, and the other end of the capacitor C21 is connected to a connection wire between the other end of the resistor R12 and the inductor L5.

5. The illumination electronic control system of the microscopic imaging device according to claim 4, wherein: the power supply indicating circuit comprises a resistor R5 and a light emitting diode D2, wherein the resistor R5 and the light emitting diode D2 are connected in series and then connected in parallel at two ends of a capacitor C3.

6. The illumination electronic control system of the microscopic imaging device according to claim 5, wherein: the pin SS of the buck conversion chip U2 is grounded through a capacitor C10, and the pin VREG of the buck conversion chip U2 is grounded through a capacitor C9; the pin VBST of the buck conversion chip U2 is connected with the pin GND of the buck conversion chip U2 in the chip through a diode; outside the chip, the pin VBST of the buck conversion chip U2 is connected with the pin SW of the buck conversion chip U2 through the ceramic chip capacitor C11.

7. The illumination electronic control system of the microscopic imaging device according to claim 6, wherein: the buck converter chip U2 is an 18V input 6A synchronous buck converter.