Control system of photoelectric sensor and packaging method thereof

Abstract

The invention discloses a control system of a photoelectric sensor and a packaging method of the control system. The control system comprises a signal processing module, a multi-channel synchronous detection unit, a dynamic temperature compensation module, a wireless communication unit, a high-precision amplification circuit, a main control circuit, an optical parameter calibration database and a comprehensive management unit. The method further comprises the steps of preprocessing a ceramic substrate, installing a photoelectric chip assembly, packaging an optical assembly in a vacuum mode, coating a stress buffer layer and depositing an electromagnetic shielding layer. The photoelectric sensor control system is combined with an innovative packaging method, and the performance and application potential of the photoelectric sensor are comprehensively improved through modular design, accurate signal processing, efficient temperature compensation, reliable communication and an optimized packaging structure.

Description

Technical Field

[0001] The present invention relates to the field of photoelectric detection technology, and in particular to a control system of a photoelectric sensor and a packaging method thereof. Background Art

[0002] A photoelectric sensor is a device that converts light signals into electrical signals. It generally consists of two parts: a processing circuit and a processing element. Based on the photoelectric effect, its fundamental principle is to convert changes in the measured quantity into changes in the light signal. The photoelectric element then further converts the non-electrical signal into an electrical signal. It is widely used in optical communications, industrial automation, medical equipment, intelligent security, and other fields.

[0003] The control system of existing photoelectric sensors has the following problems:

[0004] 1. The signal processing accuracy is insufficient and cannot meet the needs of high-end applications;

[0005] 2. The system power consumption is high, which makes it difficult to meet the needs of low-power devices;

[0006] 3. The packaging method is not perfect, which causes the sensor to easily degrade in harsh environments such as high temperature and humidity.

[0007] Therefore, how to design a photoelectric sensor control system with high precision, high reliability and high packaging performance and its packaging method has become an important topic in the current technical field. Summary of the Invention

[0008] (1) Technical problems solved

[0009] In response to the shortcomings of the existing technology, the present invention adopts a combination of a control system and a packaging method to further optimize the signal transmission path, reduce transmission loss, and improve the measurement accuracy of the overall system.

[0010] (2) Technical solution

[0011] To achieve the above-mentioned object, the present invention provides the following technical solution: a control system for a photoelectric sensor, comprising:

[0012] The signal processing module processes and optimizes the raw signals from the sensor, such as noise removal, dynamic threshold adjustment, and signal optimization:

[0013] Multi-channel synchronous detection unit with timestamp function, supports parallel sampling, single-channel sampling rate ≥ 20kHz, each channel is equipped with a 16-bit ADC at the back end, and the timestamp accuracy reaches 100ns;

[0014] Dynamic temperature compensation module, integrated with PT100 temperature sensor array, builds a three-dimensional distributed temperature sampling network, adopts non-isothermal drift compensation, compensation response time ≤ 1s, compensation accuracy ≤ 0.1%;

[0015] The wireless communication unit supports LoRa and BLE dual-mode transmission. The communication unit integrates a data encryption module, adopts the AES-128 encryption algorithm, and has 4 levels of encryption authentication for transmitted data. It also supports remote firmware upgrade function.

[0016] High-precision amplifier circuit, using low-noise amplifier technology, amplification current response time <1ms, amplification linearity >0.999, ensuring the accuracy and stability of signal acquisition;

[0017] The main control circuit realizes precise control of the dynamic temperature compensation module and works in conjunction with the execution circuit to achieve real-time adjustment and optimization of temperature compensation parameters;

[0018] Optical parameter calibration database, storing refractive index-temperature compensation curves, including more than 50 sets of environmental parameter mappings, supporting user-defined extensions and importing third-party calibration parameters;

[0019] The integrated management unit provides ambient light intensity monitoring, communication bandwidth adjustment, and system status logging functions. It supports vacuum packaging stress state monitoring and triggers calibration instructions when the buffer layer deformation rate is greater than 2%.

[0020] As a preferred solution, the signal processing module includes: an adaptive threshold adjustment unit, which uses FPGA to implement a dynamic baseline tracking algorithm with a response time of ≤5μs;

[0021] The noise filtering unit is based on the improved Kalman filtering algorithm, has an adaptive filtering band function, and supports real-time switching of different noise spectrum modes.

[0022] As a preferred solution, the multi-channel synchronous detection unit includes a light intensity compensation sub-module, which adjusts the LED driving current of each channel through feedback to achieve a lighting uniformity of >90%; the multi-channel synchronous detection unit also includes a multi-channel driving circuit, which is responsible for controlling and driving the activation and data acquisition of multiple channels to ensure the synchronization and consistency of each channel.

[0023] As a preferred solution, the dynamic temperature compensation module is θ The value is estimated online to achieve thermal drift compensation, and the compensation loop provides the following functions: temperature sampling - characteristic parameter extraction - compensation amount calculation - offset adjustment - effect feedback.

[0024] As a preferred solution, the high-precision amplification circuit and the dynamic baseline tracking algorithm work together to achieve accurate signal acquisition and real-time processing; the main control circuit and the execution circuit work together to achieve accurate control and real-time adjustment of temperature compensation parameters; the multi-channel drive circuit and the light intensity compensation sub-module work together to achieve uniformity and stability of illumination.

[0025] A method for packaging a photoelectric sensor comprises the following steps:

[0026] S1. Ceramic substrate pretreatment: UV laser engraving of light guide grooves on Al2O3 substrates, roughening of the groove bottom surface, optimization of the Raman refractive index, and control of the residual base material thickness to 5±0.5 mils;

[0027] S2. Install the optoelectronic chip assembly and secure it to the heat sink using conductive silver glue. Silver nanoparticles are added to the glue layer to optimize conductivity. The curing temperature is controlled at 150±5°C for 25 minutes.

[0028] S3. Vacuum-sealed optical components, including fine-tuning of the lens and filter angles, and the tilt angle of the lens group θ Satisfies: 3°≤θ≤15°, and forms a total reflection path with the light guide groove;

[0029] S4. Apply a stress buffer layer using a PDMS / CNT composite with a precisely controlled PDMS:CNT ratio of 10:1 (mass fraction), a coating thickness of 50-200 μm, and a thermal expansion coefficient matching error of ≤5%.

[0030] S5. Deposit the electromagnetic shielding layer using a magnetron sputtering process to form a gradient Cu / Ni stacked structure. Before deposition, the substrate surface is plasma pretreated to enhance its nucleation capability.

[0031] As a preferred solution, in S1, the light guide groove is designed as a V-shaped groove with a bottom half angle of 10°, a groove depth of 80μm, and a groove width of 100μm. The bottom surface of the groove is treated with microwave assistance to improve the properties of the light-object interface and reduce the reflection loss to below 0.5%.

[0032] As a preferred solution, the tilt angle of the lens group in S3 is θ The angle must meet the following requirements: 3°≤θ≤15°, and a total reflection path must be formed with the light guide groove. A gradient distance of 5μm±2% must be formed between the lens and the groove wall to ensure that the system maintains a light collection efficiency of >90% under different tilt states.

[0033] As a preferred solution, the thickness of the stress buffer layer in S4 is 50-200 μm, the thermal expansion coefficient matching error is ≤5%, the layer thickness uniformity is verified by polarization test and there is no obvious crack, and the average density is stable at 1.2±0.05 g / cm3 .

[0034] As a preferred solution, the temperature compensation module and the heat sink area of the packaging structure establish a heat conduction model, and the compensation coefficient K = α·(T-T0) 2 , where α = 0.0035 / °C 2 The application range of the K value is -20℃≤T-T0≤85℃, and the coefficient adaptability remains stable within the range of ±10%; the wireless communication unit realizes package stress state monitoring, and triggers the calibration instruction when the deformation rate of the buffer layer is greater than 2%. The deformation monitoring accuracy is 0.1%±0.05%, and the monitoring period is adjustable. The sampling frequency is 1Hz under normal conditions and can be changed to 10Hz under fault conditions.

[0035] (3) Beneficial effects

[0036] Compared with the prior art, the present invention provides a control system for a photoelectric sensor and a packaging method thereof, which has the following beneficial effects:

[0037] The control system of the present invention includes a signal adaptive processing module, a multi-channel synchronous detection unit, a temperature compensation module, and a wireless communication unit. The packaging method utilizes a multi-layer composite packaging process, including a self-calibrating optical component structure, a stress buffer layer, and an electromagnetic shielding layer. By optimizing the coordinated design of the photoelectric conversion path and signal processing algorithm, combined with the active regulation of the optical path refractive index and mechanical stress by the packaging structure, high-precision, interference-resistant photoelectric detection performance is achieved. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 This is a schematic diagram of the control system module structure of the present invention;

[0039] Figure 2 Schematic diagram of the packaging method of the present invention. DETAILED DESCRIPTION

[0040] In order to better understand the purpose, structure and function of the present invention, a control system of a photoelectric sensor and a packaging method thereof of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.

[0041] Example 1

[0042] refer to Figure 1-2 The present invention provides a control system for a photoelectric sensor, comprising:

[0043] The signal processing module processes and optimizes the raw signals from the sensor, such as noise removal, dynamic threshold adjustment, and signal optimization:

[0044] Multi-channel synchronous detection unit with timestamp function, supports parallel sampling, single-channel sampling rate ≥ 20kHz, each channel is equipped with a 16-bit ADC at the back end, and the timestamp accuracy reaches 100ns;

[0045] Dynamic temperature compensation module, integrated with PT100 temperature sensor array, builds a three-dimensional distributed temperature sampling network, adopts non-isothermal drift compensation, compensation response time ≤ 1s, compensation accuracy ≤ 0.1%;

[0046] The wireless communication unit supports LoRa and BLE dual-mode transmission. The communication unit integrates a data encryption module, adopts the AES-128 encryption algorithm, and has 4 levels of encryption authentication for transmitted data. It also supports remote firmware upgrade function.

[0047] High-precision amplifier circuit, using low-noise amplifier technology, amplification current response time <1ms, amplification linearity >0.999, ensuring the accuracy and stability of signal acquisition;

[0048] The main control circuit realizes precise control of the dynamic temperature compensation module and works in conjunction with the execution circuit to achieve real-time adjustment and optimization of temperature compensation parameters;

[0049] Optical parameter calibration database, storing refractive index-temperature compensation curves, including more than 50 sets of environmental parameter mappings, supporting user-defined extensions and importing third-party calibration parameters;

[0050] The integrated management unit provides ambient light intensity monitoring, communication bandwidth adjustment, and system status logging functions. It supports vacuum packaging stress state monitoring and triggers calibration instructions when the buffer layer deformation rate is greater than 2%.

[0051] The control system consists of multiple core modules that coordinate the functions of each module to accurately collect and process the photoelectric sensor signals. Its signal processing modules include: an adaptive threshold adjustment unit that uses FPGA to implement a dynamic baseline tracking algorithm with a response time of ≤5μs; a noise filtering unit based on an improved Kalman filter algorithm with an adaptive filter band function and support for real-time switching of different noise spectrum modes;

[0052] The multi-channel synchronous detection unit includes a light intensity compensation submodule, which adjusts the LED driving current of each channel through feedback to achieve a lighting uniformity of >90%; the multi-channel synchronous detection unit also includes a multi-channel driving circuit, which is responsible for controlling and driving the activation and data collection of multiple channels to ensure the synchronization and consistency of each channel; the dynamic temperature compensation module is θ The value is estimated online to achieve thermal drift compensation. The compensation loop provides the following functions: temperature sampling - characteristic parameter extraction - compensation amount calculation - offset adjustment - effect feedback;

[0053] The high-precision amplification circuit and dynamic baseline tracking algorithm work together to achieve accurate signal acquisition and real-time processing; the main control circuit and the execution circuit work together to achieve precise control and real-time adjustment of temperature compensation parameters; the multi-channel drive circuit and the light intensity compensation sub-module work together to achieve uniformity and stability of lighting.

[0054] Specifically, the signal processing module is the core processing unit of the system, mainly responsible for optimizing the processing of the original signal from the sensor. Among them, the adaptive threshold adjustment unit uses FPGA to implement a dynamic baseline tracking algorithm with a response time of less than 5 microseconds. It can quickly adapt to the dynamic changes of the signal and ensure the accuracy of signal detection. The noise filtering unit is based on an improved Kalman filtering algorithm and has an adaptive filtering band function. It can switch between different noise spectrum modes in real time. The filtering accuracy is as high as over 90%, effectively removing noise interference and ensuring the purity of the signal.

[0055] The multi-channel synchronous detection unit supports parallel sampling, with a single-channel sampling rate of up to 20kHz. A 16-bit high-precision analog-to-digital converter (ADC) is equipped on the back end, achieving a timestamp accuracy of 100 nanoseconds, ensuring precise synchronization of multi-channel data. The light intensity compensation submodule adjusts the LED drive current in each channel through feedback, achieving illumination uniformity exceeding 90%. The multi-channel drive circuit controls multi-channel activation and data acquisition, ensuring synchronization and consistency across channels and providing the foundation for high-precision measurement.

[0056] The dynamic temperature compensation module integrates a PT100 temperature sensor array, builds a three-dimensional distributed temperature sampling network, and adopts non-equal thermal drift compensation technology. The compensation response time is less than 1 second and the compensation accuracy is less than 0.1%. θ The online estimation of the value realizes thermal drift compensation. The compensation loop includes temperature sampling, characteristic parameter extraction, compensation amount calculation, offset adjustment and effect feedback to ensure the measurement accuracy of the system in different temperature environments.

[0057] The wireless communication unit uses LoRa and BLE dual-mode transmission technology to support a variety of communication scenarios. The communication unit integrates a data encryption module and uses the AES-128 encryption algorithm. The transmitted data undergoes 4-level encryption authentication to ensure data security. The system supports remote firmware upgrades for easy maintenance and function expansion.

[0058] The high-precision amplification circuit uses low-noise amplifier technology, with an amplified current response time of less than 1 millisecond and an amplification linearity higher than 0.999, ensuring the accuracy and stability of signal acquisition. The dynamic baseline tracking algorithm works in conjunction with the amplification circuit to achieve precise signal acquisition and real-time processing;

[0059] The main control circuit precisely controls the dynamic temperature compensation module and collaborates with the execution circuit to achieve real-time adjustment and optimization of temperature compensation parameters. The optical parameter calibration database stores over 50 sets of refractive index-temperature compensation curves and supports user-defined expansion and the import of third-party calibration parameters, providing support for system flexibility and adaptability.

[0060] Example 2

[0061] refer to Figure 1-2 The present invention provides a method for packaging a photoelectric sensor, comprising the following steps:

[0062] S1. Ceramic substrate pretreatment: UV laser engraving of light guide grooves on Al2O3 substrates, roughening of the groove bottom surface, optimization of the Raman refractive index, and control of the residual base material thickness to 5±0.5 mils;

[0063] S2. Install the optoelectronic chip assembly and secure it to the heat sink using conductive silver glue. Silver nanoparticles are added to the glue layer to optimize conductivity. The curing temperature is controlled at 150±5°C for 25 minutes.

[0064] S3. Vacuum-sealed optical components, including fine-tuning of the lens and filter angles, and the tilt angle of the lens group θ Satisfies: 3°≤θ≤15°, and forms a total reflection path with the light guide groove;

[0065] S4. Apply a stress buffer layer using a PDMS / CNT composite with a precisely controlled PDMS:CNT ratio of 10:1 (mass fraction), a coating thickness of 50-200 μm, and a thermal expansion coefficient matching error of ≤5%.

[0066] S5. Deposit the electromagnetic shielding layer using a magnetron sputtering process to form a gradient Cu / Ni stacked structure. Before deposition, the substrate surface is plasma pretreated to enhance its nucleation capability.

[0067] Specifically, in S1, the light guide groove is designed as a V-shaped groove with a bottom half angle of 10°, a groove depth of 80μm, and a groove width of 100μm. The bottom surface of the groove is treated with microwave assistance to improve the properties of the light-object interface and reduce the reflection loss to less than 0.5%. The tilt angle of the lens group in S3 is θ The following requirements are met: 3°≤θ≤15°, and a total reflection path is formed with the light guide groove. A gradient distance of 5μm±2% is formed between the lens and the groove wall, ensuring that the system maintains a light collection efficiency of >90% under different tilt states. The thickness of the stress buffer layer in S4 is 50-200μm, the thermal expansion coefficient matching error is ≤5%, and the layer thickness uniformity has been verified by polarization tests to have no obvious cracks. The average density is stable at 1.2±0.05g / cm 3 .

[0068] To ensure the high performance and reliability of the photoelectric sensor, the packaging method of the photoelectric sensor is now described in detail step by step:

[0069] Step S1: Ceramic substrate pretreatment

[0070] UV laser engraving technology is used to create light guide grooves on an Al2O3 ceramic substrate. The groove bottom surface is roughened to optimize the Raman refractive index. The light guide grooves are designed as V-shaped grooves with a 10° bottom half-angle, a groove depth of 80μm, and a groove width of 100μm. Microwave-assisted notching of the groove bottom surface effectively reduces reflection loss to less than 0.5%. The residual base material thickness is strictly controlled to 5±0.5 mils to ensure accurate light transmission.

[0071] Step S2: Installing the optoelectronic chip assembly

[0072] Conductive silver glue is used to secure the optoelectronic chip to the heat sink. Silver nanoparticles are added to the glue layer to optimize conductivity. The curing temperature is controlled at 150±5°C for 25 minutes to ensure the reliability and conductivity of the glue layer.

[0073] Step S3: Vacuum packaging of optical components

[0074] Fine-tune the tilt of the optical components (including lenses and filters) to ensure that the lens group tilts between 3° and 15° and forms a fully reflective path with the light guide to optimize light transmission efficiency. The vacuum packaging process strictly controls the environment to ensure the airtightness and optical performance of the package.

[0075] Step S4: Coating a stress buffer layer

[0076] The stress buffer layer is made of a composite of PDMS and carbon nanotubes, with a precisely controlled material ratio of PDMS:CNT = 10:1 (mass fraction). The coating thickness is 50-200μm, and the thermal expansion coefficient matching error is ≤5%. Polarization tests have verified that the layer thickness uniformity is free of visible cracks, and the average density is stable at 1.2±0.05g / cm. 3 , ensuring the mechanical strength and thermal stability of the buffer layer.

[0077] Step S5: Depositing an electromagnetic shielding layer

[0078] A gradient Cu / Ni stacked structure is formed using a magnetron sputtering process. The substrate surface undergoes plasma pretreatment before deposition to enhance core bonding. The electromagnetic shielding layer effectively blocks external electromagnetic interference, ensuring the system's anti-interference capabilities.

[0079] Example 3

[0080] A heat conduction model is established between the temperature compensation module and the heat sink area of the package structure, and the compensation coefficient K = α (T-T0) 2 , where α = 0.0035 / °C 2 The application range of the K value is -20℃≤T-T0≤85℃, and the coefficient adaptability remains stable within the range of ±10%. The wireless communication unit realizes the monitoring of the stress state of the package. When the deformation rate of the buffer layer is greater than 2%, the calibration instruction is triggered. The deformation monitoring accuracy is 0.1%±0.05%. The monitoring period is adjustable. The sampling frequency is 1Hz in the normal state and can be changed to 10Hz in the fault state.

[0081] Furthermore, the combination of the photoelectric sensor control system and its packaging method is the key to ensuring system performance. The dynamic temperature compensation module realizes thermal drift compensation through online estimation of the θ value, and its compensation coefficient K = α·(T-T0) 2 (where α = 0.0035 / °C 2 The application range is -20°C ≤ T - T0 ≤ 85°C, with an adaptability stable within ±10%. The wireless communication unit in the control system monitors the package stress state, triggering a calibration command when the buffer layer deformation rate exceeds 2%. The deformation monitoring accuracy is 0.1% ± 0.05%, and the monitoring cycle is adjustable. The sampling frequency is 1Hz under normal conditions and can be increased to 10Hz in fault conditions, ensuring real-time response and long-term stability of the system.

[0082] Furthermore, the main control circuit and execution circuit work together to achieve precise control and real-time adjustment of temperature compensation parameters. The multi-channel drive circuit works in conjunction with the light intensity compensation submodule to ensure uniform and stable illumination. The control system utilizes high-precision amplification circuits and a dynamic baseline tracking algorithm to ensure accurate signal acquisition and real-time processing. An optical parameter calibration database provides the system with flexible calibration capabilities, supporting user-defined and third-party parameter expansion.

[0083] In summary, this photoelectric sensor control system combines innovative packaging methods with modular design, precise signal processing, efficient temperature compensation, reliable communication, and optimized packaging structure to comprehensively improve the performance and application potential of photoelectric sensors.

[0084] It will be understood that the present invention is described by way of some embodiments, and it will be appreciated by those skilled in the art that various changes or equivalent substitutions may be made to these features and embodiments without departing from the spirit and scope of the present invention. In addition, under the teachings of the present invention, these features and embodiments may be modified to adapt to specific circumstances and materials without departing from the spirit and scope of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed herein, and all embodiments falling within the scope of the claims of this application are intended to be protected by the present invention.

Claims

1. A control system for a photoelectric sensor, comprising: The signal processing module processes and optimizes the raw signals from the sensor, such as noise removal, dynamic threshold adjustment, and signal optimization: Multi-channel synchronous detection unit with timestamp function, supports parallel sampling, single-channel sampling rate ≥ 20kHz, each channel is equipped with a 16-bit ADC at the back end, and the timestamp accuracy reaches 100ns; Dynamic temperature compensation module, integrated with PT100 temperature sensor array, builds a three-dimensional distributed temperature sampling network, adopts non-isothermal drift compensation, compensation response time ≤ 1s, compensation accuracy ≤ 0.1%; The wireless communication unit supports LoRa and BLE dual-mode transmission. The communication unit integrates a data encryption module, adopts the AES-128 encryption algorithm, and has 4 levels of encryption authentication for transmitted data. It also supports remote firmware upgrade function. High-precision amplifier circuit, using low-noise amplifier technology, amplification current response time <1ms, amplification linearity >0.999, ensuring the accuracy and stability of signal acquisition; The main control circuit realizes precise control of the dynamic temperature compensation module and works in conjunction with the execution circuit to achieve real-time adjustment and optimization of temperature compensation parameters; Optical parameter calibration database, storing refractive index-temperature compensation curves, including more than 50 sets of environmental parameter mappings, supporting user-defined extensions and importing third-party calibration parameters; The integrated management unit provides ambient light intensity monitoring, communication bandwidth adjustment, and system status logging functions. It supports vacuum packaging stress state monitoring and triggers calibration instructions when the buffer layer deformation rate is greater than 2%.

2. A photoelectric sensor control system according to claim 1, characterized in that: The signal processing module includes: an adaptive threshold adjustment unit, which uses FPGA to implement a dynamic baseline tracking algorithm with a response time of ≤5μs; The noise filtering unit is based on the improved Kalman filtering algorithm, has an adaptive filtering band function, and supports real-time switching of different noise spectrum modes.

3. The control system of a photoelectric sensor according to claim 1, characterized in that: The multi-channel synchronous detection unit includes a light intensity compensation submodule, which adjusts the LED driving current of each channel through feedback to achieve a lighting uniformity of >90%; the multi-channel synchronous detection unit also includes a multi-channel driving circuit, which is responsible for controlling and driving the activation and data acquisition of multiple channels to ensure the synchronization and consistency of each channel.

4. The control system of a photoelectric sensor according to claim 1, characterized in that: The dynamic temperature compensation module is θ The value is estimated online to achieve thermal drift compensation, and the compensation loop provides the following functions: temperature sampling - characteristic parameter extraction - compensation amount calculation - offset adjustment - effect feedback.

5. The control system of a photoelectric sensor according to claim 3, characterized in that: The high-precision amplification circuit and the dynamic baseline tracking algorithm work together to achieve accurate signal acquisition and real-time processing; the main control circuit and the execution circuit work together to achieve accurate control and real-time adjustment of temperature compensation parameters; the multi-channel drive circuit and the light intensity compensation submodule work together to achieve uniformity and stability of illumination.

6. A method for packaging a photoelectric sensor, comprising a control system for a photoelectric sensor according to any one of claims 1 to 5, characterized in that: The steps include: S1. Ceramic substrate pretreatment: UV laser engraving of light guide grooves on Al2O3 substrates, roughening of the groove bottom surface, optimization of the Raman refractive index, and control of the residual base material thickness to 5±0.5 mils; S2. Install the optoelectronic chip assembly and secure it to the heat sink using conductive silver glue. Silver nanoparticles are added to the glue layer to optimize conductivity. The curing temperature is controlled at 150±5°C for 25 minutes. S3. Vacuum-sealed optical components, including fine-tuning of the lens and filter angles, and the tilt angle of the lens group θ Satisfies: 3°≤θ≤15°, and forms a total reflection path with the light guide groove; S4. Apply a stress buffer layer using a PDMS / CNT composite with a precisely controlled PDMS:CNT ratio of 10:1 (mass fraction), a coating thickness of 50-200 μm, and a thermal expansion coefficient matching error of ≤5%. S5. Deposit the electromagnetic shielding layer using a magnetron sputtering process to form a gradient Cu / Ni stacked structure. Before deposition, the substrate surface is plasma pretreated to enhance its nucleation capability.

7. The method for packaging a photoelectric sensor according to claim 6, wherein: In S1, the light guide groove is designed as a V-shaped groove with a bottom half angle of 10°, a groove depth of 80μm, and a groove width of 100μm. The bottom surface of the groove is treated with microwave assistance to improve the properties of the light-object interface and reduce reflection loss to below 0.5%.

8. The method for packaging a photoelectric sensor according to claim 7, wherein: The tilt angle of the lens group in S3 θ The angle must meet the following requirements: 3°≤θ≤15°, and a total reflection path must be formed with the light guide groove. A gradient distance of 5μm±2% must be formed between the lens and the groove wall to ensure that the system maintains a light collection efficiency of >90% under different tilt states.

9. The method for packaging a photoelectric sensor according to claim 6, wherein: The thickness of the stress buffer layer in the S4 is 50-200 μm, the thermal expansion coefficient matching error is ≤5%, the layer thickness uniformity is verified by polarization test and there is no obvious crack, and the average density is stable at 1.2±0.05 g / cm 3 .

10. The method for packaging a photoelectric sensor according to claim 6, wherein: The temperature compensation module and the heat sink area of the packaging structure establish a heat conduction model, and the compensation coefficient K=α·(T-T0) 2 , where α = 0.0035 / °C 2 The application range of the K value is -20℃≤T-T0≤85℃, and the coefficient adaptability remains stable within the range of ±10%; the wireless communication unit realizes package stress state monitoring, and triggers the calibration instruction when the deformation rate of the buffer layer is greater than 2%. The deformation monitoring accuracy is 0.1%±0.05%, and the monitoring period is adjustable. The sampling frequency is 1Hz under normal conditions and can be changed to 10Hz under fault conditions.

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