Skin detection system and single fault state coping method

Abstract

This invention proposes a skin detection system and a method for handling single fault conditions, including a power supply, a power supply circuit, a light source driver chip, a light source, a microcontroller, multiple sets of metal sensor sheets, multiple sets of capacitive touch chips, a logic gate hardware circuit, and an overcurrent and overvoltage protection circuit. The power supply and the light source driver chip are connected through the power supply circuit, and the light source is connected to the light source driver chip. The power supply circuit and the light source driver chip are connected to the microcontroller, and the metal sensor sheets are respectively connected to the capacitive touch chips. The metal sensor sheets are connected to the logic gate hardware circuit, and the logic gate hardware circuit is connected to the light source driver chip. The power supply is connected to the overcurrent and overvoltage protection circuit. Therefore, this invention sets up a skin detection system where the light source is triggered only when the metal sensor sheets contact the skin. With the assistance of the logic gate hardware circuit, the device can still control the light source to shut off in the event of a single fault, managing the light emission status and treatment duration to ensure safety.

Description

Technical Field

[0001] This invention relates to the field of fault response technology for skin phototherapy equipment, and in particular to a skin detection system and a method for handling single fault states. Background Technology

[0002] Home-use phototherapy devices (such as ultraviolet phototherapy devices) are widely used in home care for skin diseases such as psoriasis and vitiligo. Their light radiation safety must strictly comply with standards such as GB / T20145-2006 "Photobiological Safety of Lamps and Lamp Systems" and GB9706.283—2022. These standards clearly require the assessment of stray light radiation from the device at a distance of 200mm from the emission window. Based on emission limits for different types of light sources, such as photochemical ultraviolet light, blue light, and retinal thermal hazards, devices are classified into exempt, risk class 1, risk class 2, and risk class 3 (risk class 3 is prohibited in home settings).

[0003] Despite the aforementioned standards and regulations, existing ultraviolet phototherapy equipment still poses significant safety hazards: On the one hand, the equipment is prone to accidental activation, which may lead to high-power ultraviolet light accidentally irradiating the patient's eyes and non-treatment areas of the body, exceeding the emission limits for photochemical ultraviolet exemptions in the standards, causing serious damage such as skin erythema and corneal damage, resulting in poor overall safety; on the other hand, if the equipment malfunctions due to abnormal control circuits or timing module failures, the light emission status of the light outlet and the treatment duration will be out of effective control, making it impossible to ensure that the light radiation is within the standard-permitted exposure time, further amplifying the risks of use and seriously threatening the health of inexperienced operators. Summary of the Invention

[0004] The present invention aims to at least partially solve one of the technical problems in the related art.

[0005] Therefore, the purpose of this invention is to propose a skin detection system and a method for handling single fault conditions. The skin detection system is configured such that ultraviolet light therapy can only be triggered when all metal sensor plates on it are in contact with the skin. With the assistance of logic gate hardware circuits, the device can still control the light source to shut off when a single fault occurs, effectively controlling the light emission status of the light outlet and the treatment duration to ensure safety.

[0006] To achieve the above objectives, this invention proposes a skin detection system and a method for handling single fault states, comprising a power supply, a power supply circuit, a light source driver chip, a light source, a microcontroller, multiple sets of metal sensing sheets, multiple sets of capacitive touch chips, a logic gate hardware circuit, and an overcurrent and overvoltage protection circuit. The power supply and the light source driver chip are electrically connected through the power supply circuit, and the light source is electrically connected to the light source driver chip. The power supply provides power to the light source driver chip through the power supply circuit to drive and control the operation of the light source. The light source driver chip is provided with an enable terminal for directly controlling the operation of the light source. Both the power supply circuit and the light source driver chip are electrically connected to the microcontroller. The multiple sets of metal sensing sheets are respectively electrically connected to the corresponding sets of capacitive touch chips, and the multiple sets of capacitive touch chips are all connected to the microcontroller. The microcontroller receives... The capacitive touch chip receives feedback from the capacitive touch chip and controls the power supply circuit and the light source driver chip, ensuring the light source is turned off in the event of a failure of any single component other than the microcontroller. Multiple sets of metal sensing plates are electrically connected to a logic gate hardware circuit, which is also electrically connected to the light source driver chip. This logic gate hardware circuit receives feedback from the capacitive touch chip and controls the light source driver chip, ensuring the light source is turned off in the event of a failure of any single component other than the logic gate hardware circuit. The power supply is electrically connected to an overcurrent and overvoltage protection circuit. The microcontroller, the logic gate hardware circuit, and the multiple sets of capacitive touch chips are all electrically connected to this overcurrent and overvoltage protection circuit. This overcurrent and overvoltage protection circuit provides regulated power to the multiple sets of capacitive touch chips, the microcontroller, and the logic gate hardware circuit through the power supply, while also providing overcurrent and overvoltage protection.

[0007] A method for handling a single fault condition in a skin detection system includes the following steps:

[0008] (1) When any one of the sensing element 1, sensing element 2, sensing element 3, or sensing element 4 fails, or the capacitive touch chip connected to it fails, the microcontroller outputs a low level, which turns off transistor 1, and the logic gate 2 outputs a high level, which turns on transistor 2, thereby cutting off the power supply to the drive circuit and pulling the enable terminal of the light source drive chip low to ensure that the light source output is turned off.

[0009] (2) When the microcontroller malfunctions and cannot detect the sensing state of the metal sensor, or when all pin interfaces are out of control and in a high-level state, or when the light source outlet leaves the skin, sensor one, sensor two, sensor three, and sensor four work simultaneously, the output of multiple sets of capacitive touch chips are all high level, the output of logic gate one, logic gate three, and logic gate two are all high level, transistor two is turned on, and the enable terminal of the light source driver chip is pulled low to ensure that the light source output is turned off;

[0010] (3) When the transistor in the power supply circuit of the light source driver chip fails, it will always be in the on state. As described in step (2), the enable terminal of the light source driver chip can still be pulled low by the metal sensor to ensure that the light source output is turned off.

[0011] (4) When the light source driver chip malfunctions and its enable terminal is not controlled, the microcontroller ensures that the light source output is turned off by shutting down the power supply circuit;

[0012] (5) When the logic gate hardware circuit composed of logic gate one, logic gate three, logic gate two, transistor two, etc. malfunctions, causing the enable terminal of the light source driver chip to be at a high level, as described in step (4), the microcontroller ensures that the light source output is turned off by shutting down the power supply circuit.

[0013] (6) When the power supply fails and the output voltage is too low, the microcontroller or capacitive touch chip cannot work properly. At this time, the light source cannot be lit and the light source output is turned off. When the power supply fails and the output voltage is too high, the transient suppression diode is broken down and the fuse blows quickly, cutting off the power supply to the microcontroller and capacitive touch chip, ensuring that the light source output is turned off.

[0014] In addition, the skin detection system and single-fault condition handling method proposed in the above application may also have the following additional technical features:

[0015] Specifically, the power supply circuit includes a main switch circuit and a drive circuit. The main switch circuit includes a transistor, and the drive circuit includes a transistor. The main switch circuit is electrically connected to the drive circuit. The transistor is electrically connected to the light source driver chip, and the transistor is electrically connected to the microcontroller. This allows the microcontroller to control the power supply to the light source driver chip via the transistor and transistor in the power supply circuit.

[0016] Specifically, the multiple sets of capacitive touch chips include chip one, chip two, chip three, and chip four, and the multiple sets of metal sensing sheets include sensing sheet one, sensing sheet two, sensing sheet three, and sensing sheet four. Chip one is electrically connected to sensing sheet one, chip two is electrically connected to sensing sheet two, chip three is electrically connected to sensing sheet three, and chip four is electrically connected to sensing sheet four. Each set of capacitive touch chips is equipped with a high-frequency filtering circuit and an AC coupling circuit.

[0017] Specifically, the logic gate hardware circuit includes an enable control circuit, logic gate one, logic gate two, and logic gate three. The enable control circuit includes transistor two, which is electrically connected to the light source driver chip. Logic gate one and logic gate three are electrically connected to the two input terminals of logic gate two, respectively. Chip one and chip two are electrically connected to the two input terminals of logic gate one, respectively. Chip three and chip four are electrically connected to the two input terminals of logic gate three, respectively. Logic gate two is electrically connected to transistor two.

[0018] Specifically, the overcurrent and overvoltage protection circuit includes a transient suppression diode and a fuse. The transient suppression diode is electrically connected to the fuse and to the power supply. The fuse is electrically connected to the microcontroller, the logic gate hardware circuit, and multiple sets of capacitive touch chips.

[0019] Compared with the prior art, the present invention has the following beneficial effects: 1. By setting up metal sensor sheets for skin detection, the light source can be activated only when all metal sensor sheets contact the skin and trigger the capacitive touch chip, thus avoiding the problem of accidental activation of the light source to irradiate non-treatment areas of the patient's body due to incomplete contact with the skin, thereby improving safety.

[0020] 2. If a single fault occurs in the equipment, regardless of which component is damaged, the remaining components can work together to effectively control the light output status and treatment duration at the light outlet, ensuring that the equipment can still shut off the light source normally and reduce safety risks.

[0021] Additional aspects and advantages of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. Attached Figure Description

[0022] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the following description of the embodiments taken in conjunction with the accompanying drawings, wherein:

[0023] Figure 1 This is a system block diagram of a skin detection system and a method for handling single fault states according to the present invention.

[0024] As shown in the figure: 100, power supply; 200, power supply circuit; 201, main switch circuit; 202, drive circuit; 300, light source driver chip; 400, light source; 500, microcontroller; 600, metal sensor; 700, capacitive touch chip; 800, logic gate hardware circuit; 801, enable control circuit; 900, overcurrent and overvoltage protection circuit; 901, transient suppression diode; 902, fuse. Detailed Implementation

[0025] Embodiments of the present invention are described in detail below. Examples of these embodiments are illustrated in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention. Rather, embodiments of the invention include all variations, modifications, and equivalents falling within the spirit and scope of the appended claims.

[0026] The following description, in conjunction with the accompanying drawings, illustrates an embodiment of the skin detection system and a method for handling single fault conditions according to the present invention.

[0027] like Figure 1 As shown, an embodiment of the present invention provides a skin detection system and a method for handling a single fault state, including a power supply 100, a power supply circuit 200, a light source driver chip 300, a light source 400, a microcontroller 500, multiple sets of metal sensing sheets 600, multiple sets of capacitive touch chips 700, a logic gate hardware circuit 800, and an overcurrent and overvoltage protection circuit 900.

[0028] The power supply 100 is electrically connected to the light source driver chip 300 through the power supply circuit 200, and the light source 400 is electrically connected to the light source driver chip 300. The power supply 100 supplies power to the light source driver chip 300 through the power supply circuit 200 to drive and control the operation of the light source 400. The light source driver chip 300 is provided with an enable terminal to directly control the operation of the light source 400.

[0029] The power supply circuit 200 includes a main switch circuit 201 and a drive circuit 202. The main switch circuit 201 includes a transistor, and the drive circuit 202 includes a transistor. The main switch circuit 201 and the drive circuit 202 are electrically connected. The transistor is electrically connected to the light source driver chip 300, and the transistor is electrically connected to the microcontroller 500. This allows the microcontroller 500 to control the power supply to the light source driver chip 300 through the transistor and transistor in the power supply circuit 200.

[0030] It should be noted that the power supply 100 supplies power to the light source driver chip 300 and the light source 400 through the power supply circuit 200. The light source driver chip 300 controls the operation and shutdown of the light source 400. The power supply circuit 200 consists of a main switch circuit 201 and a drive circuit 202. The main switch circuit 201 consists of a transistor and a resistor and capacitor. The drive circuit 202 consists of a transistor and a resistor and capacitor. The transistor is electrically connected to the transistor and acts as a switch. The switching of the transistor is used to control the conduction and cutoff of the transistor, thereby realizing the on / off control of the subsequent circuit.

[0031] The power supply circuit 200 and the light source driver chip 300 are both electrically connected to the microcontroller 500. Multiple sets of metal sensing sheets 600 are electrically connected to the corresponding sets of capacitive touch chips 700. The capacitive touch chips 700 are all connected to the microcontroller 500. The microcontroller 500 receives the feedback status of the capacitive touch chips 700 and controls the power supply circuit 200 and the light source driver chip 300. In the event of a failure of any single component other than the microcontroller 500, the light source 400 is turned off.

[0032] The multiple sets of capacitive touch chips 700 include chip one, chip two, chip three and chip four, and the multiple sets of metal sensing sheets 600 include sensing sheet one, sensing sheet two, sensing sheet three and sensing sheet four. Chip one is electrically connected to sensing sheet one, chip two is electrically connected to sensing sheet two, chip three is electrically connected to sensing sheet three, and chip four is electrically connected to sensing sheet four. Each set of capacitive touch chips 700 is equipped with a high-frequency filtering circuit and an AC coupling circuit.

[0033] It should be noted that after the metal sensor 600 is attached to the patient's skin, it triggers the corresponding capacitive touch chip 700. There is a one-to-one correspondence between sensor 1 and chip 1, sensor 2 and chip 2, sensor 3 and chip 3, and sensor 4 and chip 4. The capacitive touch chip 700 is triggered by the metal sensor 600. When the microcontroller 500 receives multiple sets of capacitive touch chips 700 being triggered simultaneously, it controls the power supply to the light source driver chip 300. Transistor 1 is controlled by the microcontroller 500, which in turn controls switching transistor 1, thereby realizing the control of the power supply circuit 200 by the microcontroller 500.

[0034] Among them, multiple sets of metal sensing sheets 600 are electrically connected to the logic gate hardware circuit 800, the logic gate hardware circuit 800 is electrically connected to the light source driver chip 300, the logic gate hardware circuit 800 receives the feedback status of the capacitive touch chip 700 and controls the light source driver chip 300, ensuring that the light source 400 is turned off when any single component other than the logic gate hardware circuit 800 fails.

[0035] The logic gate hardware circuit 800 includes an enable control circuit 801, logic gate one, logic gate two, and logic gate three. The enable control circuit 801 includes a transistor two, which is electrically connected to the light source driver chip 300. Logic gate one and logic gate three are electrically connected to the two input terminals of logic gate two, respectively. Chip one and chip two are electrically connected to the two input terminals of logic gate one, respectively. Chip three and chip four are electrically connected to the two input terminals of logic gate three, respectively. Logic gate two is electrically connected to transistor two.

[0036] It should be noted that the logic gate hardware circuit 800 consists of an enable control circuit 801, logic gate one, logic gate two, and logic gate three. The enable control circuit 801 consists of the core components transistor two and resistors and capacitors. Transistor two is connected to logic gate two and the light source driver chip 300, and transistor two acts as an electronic switch in this circuit. Logic gate one and logic gate three are connected to the capacitive touch chip 700. As the number of capacitive touch chips 700 increases, the corresponding number of logic gates can also increase. Logic gate one and logic gate three respond to the state of the capacitive touch chip 700 through logical judgment, and then control the on / off state of transistor two through the logical judgment of logic gate two, outputting high and low level enable signals, thereby controlling the power supply state of the light source driver chip 300 and realizing the shutdown control of the light source 400.

[0037] In addition, the above design provides dual safety control logic: First, the light source 400 is only allowed to start output when all the metal sensor sheets 600 are in contact with the skin and transmit signals to the microcontroller 500, which in turn controls the capacitive touch chip 700; Second, the circuit is equipped with a logic gate hardware circuit 800, which can directly trigger the cut-off of the light source 400 output when a single fault occurs at a single node, ensuring the safe use of the device under various abnormal conditions.

[0038] The power supply 100 is electrically connected to the overcurrent and overvoltage protection circuit 900. The microcontroller 500, the logic gate hardware circuit 800, and the multiple sets of capacitive touch chips 700 are all electrically connected to the overcurrent and overvoltage protection circuit 900. The overcurrent and overvoltage protection circuit 900 provides regulated power to the multiple sets of capacitive touch chips 700, the microcontroller 500, and the logic gate hardware circuit 800 through the power supply 100, and at the same time provides overcurrent and overvoltage protection.

[0039] The overcurrent and overvoltage protection circuit 900 includes a transient suppression diode 901 and a fuse 902. The transient suppression diode 901 is electrically connected to the fuse 902 and is electrically connected to the power supply 100. The fuse 902 is electrically connected to the microcontroller 500, the logic gate hardware circuit 800, and multiple sets of capacitive touch chips 700.

[0040] It should be noted that the transient voltage suppressor diode 901 is model TVS1, and the fuse 902 is model F1. The transient voltage suppressor diode 901 is used to protect electronic components from damage caused by instantaneous overvoltage, clamping the voltage within a safe range and protecting downstream components such as the microcontroller 500. The fuse 902 is used to protect electronic components from damage caused by instantaneous overcurrent, preventing the device from burning out due to high current.

[0041] Under normal use:

[0042] (1) The metal sensor 600 and the input pin of the capacitive touch chip 700 are connected. When the metal sensor 600 is not detected, the output of pin 3 of the capacitive touch chip 700 is high. When the metal sensor 600 is detected, the output of pin 3 of the capacitive touch chip 700 is low. The microcontroller 500 detects that the low level is valid. When the microcontroller 500 detects that sensor 1, sensor 2, sensor 3 and sensor 4 are valid at the same time, it controls transistor 1 to conduct, thereby turning on transistor 1 and realizing the power supply of the input terminal to the light source driver chip 300.

[0043] (2) When sensor 1, sensor 2, sensor 3, and sensor 4 are all active, logic gate 1 and logic gate 3 both output low level. At this time, logic gate 2 outputs low level, transistor 2 is turned off, and the enable terminal of the light source driver chip 300 is pulled high through its resistor. Combined with the relevant description in paragraph (1), the light source 400 is started to output.

[0044] (3) When any one of the sensing elements 1, 2, 3, and 4 leaves the skin, the microcontroller 500 outputs a low level, turning off transistor 1, which in turn turns off transistor 1 and cuts off the power supply to the light source driver chip 300 from the input terminal; at the same time, logic gates 1 and 3 both output a high level, logic gate 2 outputs a high level, transistor 2 conducts, and the enable terminal of the light source driver chip 300 is pulled low, so the driver circuit 202 cannot work; through the above two measures, the output of the light source 400 is ensured to be turned off at this time.

[0045] When a single fault occurs, (1) when any one of the sensing element 1, sensing element 2, sensing element 3, or sensing element 4 fails, or the capacitive touch chip 700 connected to it fails, the microcontroller 500 outputs a low level, which turns off transistor 1, and the logic gate 2 outputs a high level, which turns on transistor 2, thereby cutting off the power supply to the drive circuit 202 and pulling the enable terminal low, ensuring that the output of the light source 400 is turned off;

[0046] (2) When the microcontroller 500 malfunctions and cannot detect the sensing state of the metal sensor 600, or when all interfaces are out of control and in a high-level state, when the light outlet leaves the skin, sensor 1, sensor 2, sensor 3, and sensor 4 work simultaneously, the output of the four capacitive touch chips 700 is high, the output of logic gate 1, logic gate 3, and logic gate 2 is high, transistor 2 is turned on, and the enable terminal of the light source driver chip 300 is pulled low to ensure that the output of the light source 400 is turned off.

[0047] (3) When the transistor of the power supply circuit 200 of the light source driver chip 300 fails, it is always in the conducting state. In the same way as step (2), the enable terminal of the light source driver chip 300 can still be controlled to be pulled low by the metal sensor 600 to ensure that the output of the light source 400 is turned off.

[0048] (4) When the light source driver chip 300 malfunctions and the enable terminal is not controlled, the microcontroller 500 ensures that the output of the light source 400 is turned off by shutting down the power supply circuit 200.

[0049] (5) When the circuit composed of logic gate 1, logic gate 3, logic gate 2, transistor 2, etc. malfunctions, causing the enable terminal of the light source driver chip 300 to be at a high level, in the same way as step (4), the microcontroller 500 ensures that the output of the light source 400 is turned off by shutting down the power supply circuit 200.

[0050] (6) When the power supply 100 fails and the output voltage is too low, the microcontroller 500 or the capacitive touch chip 700 will not work properly. At this time, the light source 400 will not light up and the output of the light source 400 will be turned off. When the power supply 100 fails and the output voltage is too high, the transient suppression diode 901 will break down and the fuse 902 will blow quickly, cutting off the power supply of the power supply 100 to the microcontroller 500 and the capacitive touch chip 700, and ensuring that the output of the light source 400 is turned off.

[0051] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the invention. In this specification, the 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 a suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0052] Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of the present invention.

Claims

1. A skin detection system, characterized in that, It includes power supply, power supply circuit, light source driver chip, light source, microcontroller, multiple sets of metal sensor sheets, multiple sets of capacitive touch chips, logic gate hardware circuit and overcurrent and overvoltage protection circuit; The power supply and the light source driver chip are electrically connected through a power supply circuit. The light source and the light source driver chip are electrically connected. The power supply supplies power to the light source driver chip through the power supply circuit to drive and control the operation of the light source. The light source driver chip is provided with an enable terminal to directly control the operation of the light source. The power supply circuit and the light source driving chip are both electrically connected to the microcontroller. The multiple sets of metal sensing sheets are electrically connected to the corresponding multiple sets of capacitive touch chips. The multiple sets of capacitive touch chips are all connected to the microcontroller. The microcontroller receives the feedback status of the capacitive touch chips and controls the power supply circuit and the light source driving chip to ensure that the light source is turned off when any single component other than the microcontroller fails. Multiple sets of the aforementioned metal sensing sheets are electrically connected to a logic gate hardware circuit, which is electrically connected to a light source driver chip. The logic gate hardware circuit includes an enable control circuit, logic gate one, logic gate two, and logic gate three. Logic gate one and logic gate three are electrically connected to the two input terminals of logic gate two, respectively. Multiple sets of the aforementioned capacitive touch chips are electrically connected to the two input terminals of logic gate one, and multiple sets of capacitive touch chips are electrically connected to the two input terminals of logic gate three, respectively. The enable control circuit is electrically connected to logic gate two and the light source driver chip, respectively. The logic gate hardware circuit receives feedback from the capacitive touch chip and controls the light source driver chip, ensuring the light source is turned off when any single component other than the logic gate hardware circuit fails. The power supply is electrically connected to the overcurrent and overvoltage protection circuit. The microcontroller, logic gate hardware circuit, and multiple sets of capacitive touch chips are all electrically connected to the overcurrent and overvoltage protection circuit. The overcurrent and overvoltage protection circuit provides regulated power to the multiple sets of capacitive touch chips, microcontroller, and logic gate hardware circuit through the power supply, while also providing overcurrent and overvoltage protection.

2. The skin detection system according to claim 1, characterized in that, The power supply circuit includes a main switch circuit and a drive circuit. The main switch circuit includes a transistor, and the drive circuit includes a transistor. The main switch circuit is electrically connected to the drive circuit. The transistor is electrically connected to the light source driver chip, and the transistor is electrically connected to the microcontroller. This allows the microcontroller to control the power supply to the light source driver chip via the transistor and transistor in the power supply circuit.

3. The skin detection system according to claim 1, characterized in that, The multiple sets of capacitive touch chips include chip one, chip two, chip three, and chip four. The multiple sets of metal sensing sheets include sensing sheet one, sensing sheet two, sensing sheet three, and sensing sheet four. Chip one is electrically connected to sensing sheet one, chip two is electrically connected to sensing sheet two, chip three is electrically connected to sensing sheet three, and chip four is electrically connected to sensing sheet four. Each set of capacitive touch chips is equipped with a high-frequency filtering circuit and an AC coupling circuit.

4. The skin detection system according to claim 1, characterized in that, The enable control circuit includes transistor two, which is electrically connected to the light source driver chip, and logic gate two is electrically connected to transistor two.

5. A skin detection system according to claim 1, characterized in that, The overcurrent and overvoltage protection circuit includes a transient suppression diode and a fuse. The transient suppression diode is electrically connected to the fuse and to the power supply. The fuse is electrically connected to the microcontroller, the logic gate hardware circuit, and multiple sets of capacitive touch chips.

6. A method for handling a single fault state in a skin detection system, used in the skin detection system according to any one of claims 1-5, characterized in that, Includes the following steps: (1) When any one of the sensing element 1, sensing element 2, sensing element 3, or sensing element 4 fails, or the capacitive touch chip connected to it fails, the microcontroller outputs a low level, which turns off transistor 1, and the logic gate 2 outputs a high level, which turns on transistor 2, thereby cutting off the power supply to the drive circuit and pulling the enable terminal of the light source drive chip low to ensure that the light source output is turned off. (2) When the microcontroller malfunctions and cannot detect the sensing state of the metal sensor, or when all pin interfaces are out of control and in a high-level state, or when the light source outlet leaves the skin, sensor one, sensor two, sensor three, and sensor four work simultaneously, the output of multiple sets of capacitive touch chips are all high level, the output of logic gate one, logic gate three, and logic gate two are all high level, transistor two is turned on, and the enable terminal of the light source driver chip is pulled low to ensure that the light source output is turned off; (3) When the transistor in the power supply circuit of the light source driver chip fails, it will always be in the on state. As described in step (2), the enable terminal of the light source driver chip can still be pulled low by the metal sensor to ensure that the light source output is turned off. (4) When the light source driver chip malfunctions and its enable terminal is not controlled, the microcontroller ensures that the light source output is turned off by shutting down the power supply circuit; (5) When the logic gate hardware circuit composed of logic gate one, logic gate three, logic gate two, transistor two, etc. malfunctions, causing the enable terminal of the light source driver chip to be at a high level, as described in step (4), the microcontroller ensures that the light source output is turned off by shutting down the power supply circuit. (6) When the power supply fails and the output voltage is too low, the microcontroller or capacitive touch chip cannot work properly. At this time, the light source cannot be lit and the light source output is turned off. When the power supply fails and the output voltage is too high, the transient suppression diode is broken down and the fuse blows quickly, cutting off the power supply to the microcontroller and capacitive touch chip, ensuring that the light source output is turned off.

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