Light compensation circuit, pulse blood oxygen simulation system and light compensation method
By designing a light compensation circuit, the system can monitor and simulate ambient light signals in real time, thus solving the problem of interference from ambient light in the pulse oximeter and improving detection accuracy.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- CONTEC MEDICAL SYST
- Filing Date
- 2024-11-20
- Publication Date
- 2026-05-22
AI Technical Summary
Existing pulse oximeters are susceptible to interference from varying ambient light, leading to inaccurate test results.
Design a light compensation circuit, including an ambient light detection circuit, an ambient light simulation generation circuit, and a compensation superposition circuit. The circuit uses components such as a light sensor, an operational amplifier, and a microprocessor to monitor and simulate ambient light signals in real time, and then performs superposition processing to resist light interference.
It improves the detection accuracy of the pulse oximeter under different lighting conditions and enhances its resistance to ambient light interference.
Smart Images
Figure CN122070872A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of blood oxygen detection technology, and in particular to a light compensation circuit, a pulse oximetry simulation system, and a light compensation method. Background Technology
[0002] The working principle of a pulse oximeter is based on the absorption spectral characteristics of oxyhemoglobin and deoxyhemoglobin in the red and near-infrared light regions. Two beams of light with different wavelengths, such as 660nm red light and 940nm near-infrared light, are used to illuminate areas like the fingers, toes, or earlobes. A photosensitive element detects the intensity of the transmitted (or reflected) photoplethysmography (PPG). These tissues are mixed tissues composed of skin, blood, muscle, and bone. The PPG formed by light passing through these tissues is characterized by a large stable component (or DC component) superimposed with a smaller pulsating component (or AC component). The AC component is caused by blood filling the arteries, while the DC component is the absorption of light by non-arterial parts such as muscle, venous blood, skin, and bone tissue as blood flows through the arteries. By measuring the PPG of the two beams, four variables can be obtained: the red light DC component, the red light AC component, the infrared DC component, and the infrared AC component. Blood oxygen saturation values can be calculated from these four components.
[0003] In related technologies, pulse oximeters are often used to test their performance and determine their quality or reliability using pulse oximeter simulators. Furthermore, to enable pulse oximeter simulators to measure blood oxygen saturation under normal lighting conditions, the pulse oximeter simulator's pulse oximeter simulation system is equipped with an ambient light interference function.
[0004] However, in actual testing, pulse oximeters are often affected by varying ambient light, which impairs their ambient light interference settings and thus affects the accuracy of the pulse oximeter's test results. Summary of the Invention
[0005] This invention provides a light compensation circuit to solve the technical problem that existing pulse oximeters are usually affected by different ambient light, which affects their own ambient light interference function and thus affects the accuracy of the pulse oximeter's detection results.
[0006] This invention provides a light compensation circuit, comprising: an ambient light detection circuit, an ambient light simulation generation circuit, and a compensation superposition circuit; The ambient light detection circuit includes a light sensor, a first operational amplifier, a first resistor, and a microprocessor. The optical sensor is connected to the inverting input of the first operational amplifier, the inverting input of the first operational amplifier is connected to the output of the first operational amplifier through the first resistor, and the output of the first operational amplifier is connected to the input of the digital-to-analog converter port of the microprocessor. The output of the digital-to-analog converter port of the microprocessor is connected to the first input of the compensation superposition circuit, and the output of the ambient light simulation generation circuit is connected to the second input of the compensation superposition circuit.
[0007] In some embodiments, the optical sensor includes a silicon photovoltaic cell, wherein the silicon photovoltaic cell comprises one or more.
[0008] In some embodiments, the microprocessor further includes an optical signal averaging processing module, which is connected to the digital-to-analog converter port of the microprocessor; The optical signal averaging module receives ambient light signals from multiple silicon photovoltaic cells transmitted through the digital-to-analog converter port of the microprocessor, and sends the averaged ambient light signals to the digital-to-analog converter port of the microprocessor.
[0009] In some embodiments, the optical sensor is installed at the simulated sensing position of the pulse oximeter, the simulated sensing position of the pulse oximeter corresponding to the sensing position of the pulse oximeter, and the optical sensor is used to collect ambient light at the sensing position of the pulse oximeter.
[0010] In some embodiments, the microprocessor further includes an optical signal calibration module, which is connected to the digital-to-analog converter port of the microprocessor; The optical signal calibration module receives the ambient light signal transmitted from the digital-to-analog converter port of the microprocessor and sends the calibrated ambient light signal to the digital-to-analog converter port of the microprocessor.
[0011] In some embodiments, the compensation superposition circuit includes a second operational amplifier and a second resistor, the first input terminal of the compensation superposition circuit includes the non-inverting input terminal of the second operational amplifier, and the second input terminal of the compensation superposition circuit includes the inverting input terminal of the second operational amplifier; The inverting input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier through the second resistor.
[0012] In some embodiments, the ambient light simulation generation circuit includes a digital-to-analog converter, and the output terminal of the ambient light simulation generation circuit includes the analog voltage output port of the digital-to-analog converter.
[0013] In some embodiments, it also includes: Charge pump circuit; The input terminal of the charge pump circuit is connected to the output terminal of the compensation superposition circuit. The input terminal of the charge pump circuit receives the voltage signal output by the compensation superposition circuit, and the output terminal of the charge pump circuit outputs the converted current signal. The charge pump circuit includes a third operational amplifier, a MOSFET, a third resistor, and a fourth resistor. The non-inverting input terminal of the third operational amplifier is connected to the output terminal of the compensation superposition circuit through the third resistor, the inverting input terminal of the third operational amplifier is grounded through the fourth resistor, and the inverting input terminal of the third operational amplifier is connected to the output terminal of the third operational amplifier through the MOS transistor.
[0014] The present invention also provides a pulse oximetry simulation system, the pulse oximetry simulation system including an interference module, the interference module being used to set the ambient light signal for the light interference function; The interference module includes the light compensation circuit described in any of the above descriptions.
[0015] The present invention also provides a light compensation method, applied to any of the light compensation circuits described above, the method comprising: Ambient light signals are acquired based on an ambient light detection circuit; Acquire the ambient light simulation signal generated by the ambient light simulation generation circuit; The ambient light signal and the ambient light analog signal are input to the compensation superposition circuit to obtain the compensated ambient light signal output by the compensation superposition circuit.
[0016] The light compensation circuit proposed in this invention includes an ambient light detection circuit, an ambient light simulation generation circuit, and a compensation superposition circuit. The ambient light detection circuit includes a light sensor, a first operational amplifier, a first resistor, and a microprocessor. The light sensor is connected to the inverting input of the first operational amplifier, which is connected to its output via the first resistor. The output of the first operational amplifier is connected to the input of the microprocessor's digital-to-analog converter (DAC). The output of the DAC is connected to the first input of the compensation superposition circuit, and the output of the ambient light simulation generation circuit is connected to its second input. Thus, the light compensation circuit monitors the intensity of ambient light in real time through the ambient light detection circuit and converts it into an electrical signal. Simultaneously, the ambient light simulation generation circuit simulates the ambient light set by the system. The compensation superposition circuit then superimposes the detected ambient light signal with the simulated ambient light signal, effectively improving the system's resistance to ambient light interference. Attached Figure Description
[0017] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.
[0018] Figure 1 This is one of the structural schematic diagrams of the light compensation circuit provided by the present invention.
[0019] Figure 2 This is the second schematic diagram of the light compensation circuit provided by the present invention.
[0020] Figure 3 This is the third schematic diagram of the light compensation circuit provided by the present invention.
[0021] Figure 4 This is the fourth schematic diagram of the light compensation circuit provided by the present invention.
[0022] Figure label: Ambient light detection circuit 10; light sensor 101; first operational amplifier 102; first resistor 103; microprocessor 104; ambient light simulation generation circuit 20; compensation superposition circuit 30; second operational amplifier 301; second resistor 302; charge pump circuit 40; third operational amplifier 401; MOS transistor 402; third resistor 403; fourth resistor 404. Detailed Implementation
[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0024] In the description of this invention, it should be understood that the terms "upper," "middle," "outer," "inner," etc., which indicate orientation or positional relationship, are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the components or elements referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as limiting this invention.
[0025] Please see Figure 1-4 As shown, the present invention is a light compensation circuit, including: an ambient light detection circuit 10, an ambient light simulation generation circuit 20, and a compensation superposition circuit 30; Here, the ambient light detection circuit 10 is used to detect the intensity of ambient light and convert it into an ambient light signal. The ambient light simulation generation circuit 20 is used to generate a simulated ambient light signal, and the compensation superposition circuit 30 is used to superimpose the ambient light signal detected by the ambient light detection circuit 10 with the simulated ambient light signal generated by the ambient light simulation generation circuit 20 to generate a compensated light signal.
[0026] The ambient light detection circuit 10 includes a light sensor 101, a first operational amplifier 102, a first resistor 103, and a microprocessor 104.
[0027] Here, the light sensor 101 is used to convert the received ambient light intensity into an ambient light signal, i.e., a current signal, and its output is proportional to the light intensity. That is, the light sensor 101 is a component that can respond to changes in ambient light intensity; when the ambient light intensity changes, the output current signal of the light sensor 101 will also change accordingly.
[0028] The first operational amplifier 102 is an amplifier with high input impedance, low output impedance, and differential input characteristics. Here, the first operational amplifier 102 is configured as a current-to-voltage converter.
[0029] The first resistor 103 is used to form a feedback loop. Since the open-loop gain of the first operational amplifier 102 is very high, the feedback loop formed by the first resistor 103 can ensure that the voltage difference between the inverting input terminal and the non-inverting input terminal of the first operational amplifier 102 is very small, thereby achieving accurate current-to-voltage conversion.
[0030] Specifically, the light sensor 101 is connected to the inverting input terminal of the first operational amplifier 102, the inverting input terminal of the first operational amplifier 102 is connected to the output terminal of the first operational amplifier 102 through the first resistor 103, and the output terminal 102b of the first operational amplifier 102 is connected to the input terminal of the digital-to-analog converter port (DAC) of the microprocessor 104. The output of the digital-to-analog converter (DAC) port of the microprocessor 104 is connected to the first input of the compensation superposition circuit 30, and the output of the ambient light simulation generation circuit 20 is connected to the second input of the compensation superposition circuit 30.
[0031] It should be noted that the light sensor 101 is connected to the inverting input of the first operational amplifier 102. Due to the characteristics of the first operational amplifier 102, the voltage at the inverting input of the first operational amplifier 102 will try to remain the same as that at the non-inverting input, but since it is an inverting input, its voltage is the opposite of the voltage at the non-inverting input. The light sensor 101 is connected to the inverting input of the first operational amplifier 102, and is also connected to the output terminal 102b of the first operational amplifier 102 through the first resistor 103 (feedback resistor), forming negative feedback, so that the output voltage of the first operational amplifier 102 is proportional to the output current of the light sensor 101.
[0032] Furthermore, the digital-to-analog converter (DAC) port of the microprocessor 104 has an analog input function, which can be used to read external analog signals. In this embodiment, by connecting the output terminal 102b of the first operational amplifier 102 to the DAC port of the microprocessor 104, the microprocessor 104 can read the voltage signal converted by the light sensor 101 and the first operational amplifier 102. This voltage signal reflects the intensity of light. The microprocessor 104 can convert this analog signal into a digital signal through its built-in analog-to-digital converter, and then further process this digital signal, such as performing threshold judgment, data analysis, etc., thereby realizing the dynamic detection of the light intensity of the working environment.
[0033] The light compensation circuit proposed in this invention monitors the intensity of ambient light in real time through the ambient light detection circuit 10 and converts it into an electrical signal; at the same time, the ambient light simulation generation circuit 20 can simulate the ambient light set by the system; then the compensation superposition circuit 30 superimposes the real-time detected ambient light signal and the simulated ambient light signal, which effectively improves the system's resistance to ambient light interference.
[0034] In some embodiments, the light sensor 101 includes a silicon photovoltaic cell, wherein the silicon photovoltaic cell comprises one or more.
[0035] A silicon photovoltaic cell is a photoelectric device that converts light energy into electrical energy. When light shines on a silicon photovoltaic cell, it generates a current that is proportional to the light intensity. The stronger the light intensity, the greater the current generated.
[0036] For applications requiring higher detection accuracy or with complex and variable lighting conditions, multiple silicon photodiodes can be used. These photodiodes can be connected in parallel or series. By spatially distributing multiple photodiodes, the light intensity at different locations can be detected, thus obtaining spatial lighting distribution information. Furthermore, if one photodiode fails, the others can still function, thereby improving system reliability.
[0037] In some embodiments, the microprocessor 104 further includes an optical signal averaging processing module, which is connected to the digital-to-analog converter (DAC) port of the microprocessor 104. The optical signal averaging module receives ambient light signals from multiple silicon photovoltaic cells transmitted by the digital-to-analog converter port (DAC) of the microprocessor 104, and sends the averaged ambient light signals to the DAC of the microprocessor 104.
[0038] In this embodiment, multiple silicon photovoltaic cells operate in parallel at the same time, each detecting ambient light and outputting a corresponding ambient light signal. These parallel ambient light signals are sent to the optical signal averaging module of the microprocessor 104. The optical signal averaging module receives ambient light signals detected by multiple silicon photovoltaic cells at the same time, representing ambient light intensities at different locations or angles. By averaging these ambient light signals from different silicon photovoltaic cells, a more comprehensive and representative ambient light signal is obtained. The calculated averaged ambient light signal is then sent back to the digital-to-analog converter (DAC) port of the microprocessor 104 for use in the subsequent compensation and superposition circuit 30.
[0039] In some embodiments, the light sensor 101 is installed at the simulated sensing position of the pulse oximeter, the simulated sensing position of the pulse oximeter corresponding to the sensing position of the pulse oximeter, and the light sensor is used to collect ambient light at the sensing position of the pulse oximeter.
[0040] Here, the simulated sensing position of the pulse oximeter refers to the location of the pulse oximeter probe (such as a finger or ear) when the instrument simulates actual pulse oximetry. The sensing position of the pulse oximeter refers to the position where the pulse oximeter probe contacts the human body (such as a finger or ear) to perform pulse oximetry.
[0041] In this embodiment, the simulated sensing position (such as a simulated finger) of the pulse oximeter needs to correspond to the sensing position of the pulse oximeter. This means that during the test, the simulated finger should be placed in the correct position of the pulse oximeter's pulse oximeter probe to ensure that the simulated pulse oximeter data can be accurately received and interpreted by the pulse oximeter.
[0042] In this embodiment, the light sensor 101 is installed as close as possible to the sensing position of the pulse oximeter, for example, on the housing of the simulated finger side of the pulse oximeter, or near the housing of the simulated finger. This ensures that the light sensor 101 can capture the same or similar ambient light conditions as in actual use.
[0043] In some embodiments, the microprocessor 104 further includes an optical signal calibration module, which is connected to the digital-to-analog converter (DAC) port of the microprocessor 104. The optical signal calibration module receives the ambient light signal transmitted from the digital-to-analog converter port (DAC) of the microprocessor 104, and sends the calibrated ambient light signal to the DAC of the microprocessor 104.
[0044] Specifically, during the initial test, the optical signal calibration module records and stores the initial ambient light signal. In subsequent tests, the optical signal calibration module receives the current ambient light signal and compares it with the recorded initial ambient light signal. Through comparison, the calibration module adjusts the current ambient light signal as needed to compensate for any deviations and ensure signal accuracy. The calibrated ambient light signal is then sent back to the digital-to-analog converter (DAC) port of the microprocessor 104.
[0045] In some embodiments, the compensation superposition circuit 30 includes a second operational amplifier 301 and a second resistor 302. The first input terminal of the compensation superposition circuit 30 includes the non-inverting input terminal of the second operational amplifier 301, and the second input terminal of the compensation superposition circuit 30 includes the inverting input terminal of the second operational amplifier 301. The inverting input terminal of the second operational amplifier 301 is connected to the output terminal of the second operational amplifier 301 through the second resistor 302.
[0046] In this embodiment, the compensation superposition circuit 30 is able to process two input signals and generate a superimposed and compensated output signal.
[0047] The non-inverting input of the second operational amplifier 301 is connected to the output 102b of the first operational amplifier 102, and the inverting input is connected to the output of the ambient light simulation generation circuit 20. When the ambient light signal is input to the non-inverting input of the second operational amplifier 301 through the output 102b of the first operational amplifier 102, the second operational amplifier 301 begins to process the signal. Simultaneously, the ambient light simulation signal from the output of the ambient light simulation generation circuit 20 is input to the inverting input of the second operational amplifier 301. The inverting input of the second operational amplifier 301 is connected to its output through a second resistor 302, forming a feedback loop. This feedback loop allows the second operational amplifier 301 to adjust its output signal according to changes in the input signal; that is, the second operational amplifier 301 keeps the voltage difference between the two inputs zero. At this time, the output of the second operational amplifier 301 generates a signal, which is the compensated ambient light signal.
[0048] In some embodiments, the ambient light simulation generation circuit 20 includes a digital-to-analog converter, and the output terminal of the ambient light simulation generation circuit 20 includes the analog voltage output port of the digital-to-analog converter.
[0049] The ambient light simulation generation circuit 20 is responsible for simulating and generating a signal corresponding to ambient light. The ambient light simulation generation circuit 20 includes a digital-to-analog converter, which is the core component for generating the analog signal.
[0050] A digital-to-analog converter (DPC) is an electronic device that converts digital signals into analog signals. In the ambient light simulation generation circuit 20, the DPC outputs a corresponding analog voltage representing the intensity of the simulated ambient light.
[0051] Specifically, in the pulse oximeter, the analog voltage output port of the ambient light simulation generation circuit 20 is connected to the compensation superposition circuit 30. In this way, the analog voltage signal generated by the analog voltage output port can be compared and compensated with the actually detected ambient light signal. Through the signal output by the simulation generation circuit, the system can simulate different ambient light conditions, thereby testing and evaluating the performance of the pulse oximeter under different lighting environments.
[0052] In some embodiments, it also includes: Charge pump circuit 40; The input terminal of the charge pump circuit 40 is connected to the output terminal of the compensation superposition circuit 30. The input terminal of the charge pump circuit 40 receives the voltage signal output by the compensation superposition circuit 30, and the output terminal of the charge pump circuit 40 outputs the converted current signal.
[0053] A charge pump circuit 40 typically consists of capacitors, switches, and possibly control logic. These components work together to achieve voltage conversion by carefully timing and controlling the switching on and off, utilizing the charge transfer characteristics of the capacitors.
[0054] Specifically, the charge pump circuit 40 is used to convert the input voltage signal into a current signal. This is achieved by controlling the on / off state of a switch and utilizing the charging and discharging process of a capacitor. During the conversion process, the charge pump circuit 40 can maintain a stable output current, thereby providing a stable output signal.
[0055] In some embodiments, the charge pump circuit 40 includes a third operational amplifier 401, a MOSFET 402, a third resistor 403, and a fourth resistor 404. The non-inverting input terminal of the third operational amplifier 401 is connected to the output terminal of the compensation superposition circuit 30 through the third resistor 403, the inverting input terminal of the third operational amplifier 401 is grounded through the fourth resistor 404, and the inverting input terminal of the third operational amplifier 401 is connected to the output terminal of the third operational amplifier 401 through the MOS transistor 402.
[0056] In this embodiment, in the charge pump circuit 40, the output signal of the compensation superposition circuit 30, i.e., the output terminal of the second operational amplifier 301, is connected to the non-inverting input terminal of the third operational amplifier 401 through the third resistor 403. This signal is the ambient light signal after preliminary compensation. The inverting input terminal of the third operational amplifier 401 is grounded through the fourth resistor 404, providing a stable reference point for the third operational amplifier 401.
[0057] Furthermore, the source (S) terminal of MOSFET 402 is connected to the inverting input terminal of the third operational amplifier 401, and the gate (G) terminal is connected to the output terminal of the third operational amplifier 401. The drain (D) terminal serves as the final output terminal, outputting the compensated ambient light signal processed by the charge pump circuit 40.
[0058] When the voltage at the output of the third operational amplifier 401 changes, the conduction state of the MOSFET 402 also changes, thus affecting the voltage at the inverting input of the third operational amplifier 401. This feedback mechanism allows the circuit to further amplify and adjust the signal. After processing by the third operational amplifier 401 and the MOSFET 402, the drain of the MOSFET 402 outputs the final compensated ambient light signal. This signal has been optimized by the charge pump circuit 40 and can more accurately reflect changes in ambient light.
[0059] The present invention also provides a pulse oximetry simulation system, which includes an interference module for setting the ambient light signal for light interference function; wherein, the interference module includes the light compensation circuit provided in the above embodiments.
[0060] Specifically, the pulse oximetry simulation system also includes a data acquisition module, a display module, a power supply module, a microprocessor, a data processing module, an output module, a keyboard module, a feedback circuit, and LEDs. The microprocessor is communicatively connected to the power supply module, the display module, the data processing module, the keyboard module, and the interference module. The output module, the feedback circuit, and the interference module are all connected to the LEDs.
[0061] The display module displays setting information, the power module provides power to all modules, the keyboard module sets the simulated blood oxygen information or other information, the output module outputs the simulated blood oxygen information, the acquisition module acquires the light signal emitted by the device under test, the output of the acquisition module connects to the input of the data processing module, and sends the acquired information to the data processing module. The data processing module modulates the acquired information according to the preset blood oxygen information, and the processed signal drives the LED to emit light through the output module. The microprocessor processes the input of the key module and outputs it to the display module for display, while simultaneously outputting the preset blood oxygen information to the data processing module for modulation. The feedback circuit adjusts the light intensity of the LED, and the interference module sets the ambient light signal for the light interference function.
[0062] The present invention also provides a light compensation method, applied to the light compensation circuit provided in the above embodiments. The method includes: Ambient light signals are acquired based on an ambient light detection circuit; Acquire the ambient light simulation signal generated by the ambient light simulation generation circuit; The ambient light signal and the ambient light analog signal are input to the compensation superposition circuit to obtain the compensated ambient light signal output by the compensation superposition circuit.
[0063] In this embodiment of the invention, the ambient light detection circuit monitors the intensity of the surrounding ambient light in real time and converts it into an electrical signal; at the same time, the ambient light simulation generation circuit can simulate the ambient light set by the system; then the compensation superposition circuit superimposes and compensates the real-time detected ambient light signal with the simulated ambient light signal, which effectively improves the system's resistance to ambient light interference.
[0064] In the description of this specification, references to terms such as "an embodiment," "example," "specific example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.
[0065] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the specification and its full scope and equivalents.
Claims
1. A light compensation circuit, characterized in that, include: Ambient light detection circuit, ambient light simulation generation circuit and compensation superposition circuit; The ambient light detection circuit includes a light sensor, a first operational amplifier, a first resistor, and a microprocessor. The optical sensor is connected to the inverting input of the first operational amplifier, the inverting input of the first operational amplifier is connected to the output of the first operational amplifier through the first resistor, and the output of the first operational amplifier is connected to the input of the digital-to-analog converter port of the microprocessor. The output of the digital-to-analog converter port of the microprocessor is connected to the first input of the compensation superposition circuit, and the output of the ambient light simulation generation circuit is connected to the second input of the compensation superposition circuit.
2. The light compensation circuit according to claim 1, characterized in that, The optical sensor includes a silicon photovoltaic cell, wherein the silicon photovoltaic cell comprises one or more.
3. The light compensation circuit according to claim 2, characterized in that, The microprocessor also includes an optical signal averaging processing module, which is connected to the digital-to-analog converter port of the microprocessor. The optical signal averaging module receives ambient light signals from multiple silicon photovoltaic cells transmitted through the digital-to-analog converter port of the microprocessor, and sends the averaged ambient light signals to the digital-to-analog converter port of the microprocessor.
4. The light compensation circuit according to claim 1, characterized in that, The optical sensor is installed at the simulated sensing position of the pulse oximeter, which corresponds to the sensing position of the pulse oximeter. The optical sensor is used to collect ambient light at the sensing position of the pulse oximeter.
5. The light compensation circuit according to claim 1, characterized in that, The microprocessor also includes an optical signal calibration module, which is connected to the digital-to-analog converter port of the microprocessor. The optical signal calibration module receives the ambient light signal transmitted from the digital-to-analog converter port of the microprocessor and sends the calibrated ambient light signal to the digital-to-analog converter port of the microprocessor.
6. The light compensation circuit according to claim 1, characterized in that, The compensation superposition circuit includes a second operational amplifier and a second resistor. The first input terminal of the compensation superposition circuit includes the non-inverting input terminal of the second operational amplifier, and the second input terminal of the compensation superposition circuit includes the inverting input terminal of the second operational amplifier. The inverting input terminal of the second operational amplifier is connected to the output terminal of the second operational amplifier through the second resistor.
7. The light compensation circuit according to claim 1, characterized in that, The ambient light simulation generation circuit includes a digital-to-analog converter, and the output terminal of the ambient light simulation generation circuit includes the analog voltage output port of the digital-to-analog converter.
8. The light compensation circuit according to claim 1, characterized in that, Also includes: Charge pump circuit; The input terminal of the charge pump circuit is connected to the output terminal of the compensation superposition circuit. The input terminal of the charge pump circuit receives the voltage signal output by the compensation superposition circuit, and the output terminal of the charge pump circuit outputs the converted current signal. The charge pump circuit includes a third operational amplifier, a MOSFET, a third resistor, and a fourth resistor. The non-inverting input terminal of the third operational amplifier is connected to the output terminal of the compensation superposition circuit through the third resistor, the inverting input terminal of the third operational amplifier is grounded through the fourth resistor, and the inverting input terminal of the third operational amplifier is connected to the output terminal of the third operational amplifier through the MOS transistor.
9. A pulse oximetry simulation system, characterized in that, The pulse oximetry simulation system includes an interference module, which is used to set the ambient light signal for the light interference function. The interference module includes the light compensation circuit as described in any one of claims 1 to 8.
10. A light compensation method, applied to the light compensation circuit according to any one of claims 1 to 8, the method comprising: Ambient light signals are acquired based on an ambient light detection circuit; Acquire the ambient light simulation signal generated by the ambient light simulation generation circuit; The ambient light signal and the ambient light analog signal are input to the compensation superposition circuit to obtain the compensated ambient light signal output by the compensation superposition circuit.