Multiband spectrum acquisition and signal enhancement structure based on light guide film

Abstract

The invention discloses a multiband spectrum acquisition and signal enhancement structure based on a light guide film, which realizes high signal-to-noise ratio acquisition of multiband spectrum signals of human skin by optimizing grating period, wave band selection, light path design and an anti-interference structure. The multi-layer grating array is arranged side by side in a partitioned mode, the period and depth of green light, red light, near-infrared light I and near-infrared light II are optimized respectively, the grating period is set to be 0.6-1.0 time of the corresponding central wavelength, and the coupling efficiency of each wave band is 70-85%. The optical path separation structure adopts a wavelength light splitting film and a narrow-band optical filter, and the crosstalk rate is less than or equal to 5%. The anti-ambient light interference layer adopts multi-layer dielectric film, polarization filtering and light source modulation synchronization, and the ambient light attenuation is greater than or equal to 90%. The skin color adaptive structure is composed of multiple depth gratings and outputs multiple depth spectral data for skin color correction. The motion artifact suppression structure adopts a 5 * 5 sensor array, outputs multiple paths of space redundant optical signals, and performs graded weighting (vlt, 1 mm / s is reduced by 0.8 times, 1-3 mm / s is reduced by 0.5 times, and the motion artifact is reduced by 0.2 times greater than or equal to 3 mm / s) on the motion speed, the motion artifact attenuation is 85%, and the signal-to-noise ratio is improved by 3-5 times. The temperature compensation structure comprises a temperature sensor and a low thermal expansion material and outputs temperature data for signal correction. The system provides a high-quality signal source for health monitoring, and is a core infrastructure for health monitoring of the light guide film.

Description

A multi-band spectral acquisition and signal enhancement structure based on photoconductive film Technical Field

[0001] This invention relates to the fields of optical data acquisition, micro / nano structure design, and biometric monitoring technology. Specifically, it relates to a multi-band spectral acquisition and signal enhancement structure based on a photoconductive film. By optimizing the grating period, band selection, optical path design, and anti-interference structure, it achieves high signal-to-noise ratio acquisition of multi-band spectral signals from human skin. This structure can be widely applied in health monitoring (blood pressure, blood oxygen, blood glucose, heart rate variability, etc.), identity recognition, and security protection scenarios, solving the problem of poor signal quality in existing photoconductive films under low light conditions, skin color differences, and motion interference. (Prior application cited)

[0002] This application is based on the applicant's prior patent application technology, specifically cited as follows: 1. Prior patent application (Application No. 2026102814971, Application Date 2026-03-10, Invention Title: A Method for Implementing Unauthorized AI Interaction Based on Photoconductive Tempered Glass Film). This patent discloses the passive optical acquisition basic structure of a photoconductive film, including a micro / nano grating array, directional light guiding, and stray light filtering mechanism. The photoconductive film basic structure in this application is based on this patent, and structural optimization and signal enhancement are performed on this basis.

[0003] 2. A prior patent application (application number 2026103505829, application date 2026-03-20, invention title: A method and system for unique identification of human optical spectral features based on photoconductive film) discloses a method for unique identification of human optical spectral features, including multi-band spectral acquisition. The multi-band spectral acquisition scheme in this application reuses the band selection logic of that patent and optimizes and extends it.

[0004] 3. Various health monitoring patents submitted by the applicant: This application provides optimized photoconductor film structures for various health monitoring patents (blood pressure, blood oxygen, blood glucose, heart rate variability, arteriosclerosis, sleep, metabolism, fatigue driving, health trends, etc.), improving signal acquisition quality. The aforementioned prior basic patents were all filed earlier than this application and were not published before the filing date of this application; therefore, they do not constitute prior art for this application. Background Technology

[0005] As a passive optical acquisition layer, the core advantage of photoconductive film is that it does not require chips, circuits, or independent power supplies, and provides a light source through the terminal screen or ambient light. However, existing photoconductor structures have the following drawbacks: 1. Single grating period: Existing photoconductors use a fixed grating period (e.g., 500nm-2μm), which cannot be optimized for different wavelengths (visible light, near-infrared), resulting in low coupling efficiency for specific wavelengths; 2. Insufficient wavelength selection: Health monitoring requires simultaneous acquisition of multiple wavelengths (e.g., blood pressure requires green light + red light, blood glucose requires multiple near-infrared wavelengths), and existing photoconductors cannot optimize multiple wavelengths simultaneously; 3. Insufficient signal-to-noise ratio: In low-light environments (nighttime, indoors), with dark-skinned individuals, and under motion interference, the signal-to-noise ratio of the acquired signal is low, affecting measurement accuracy; 4. Weak anti-interference capability: Ambient light (sunlight, artificial light) interference is severe, and existing photoconductors lack effective anti-interference design; 5. Uncorrected skin color differences: Different skin colors have large differences in light absorption / reflection, and existing photoconductors have not optimized their structure for skin color differences; 6. Sensitive to motion artifacts: Finger micro-movements and hand movements during pulse wave acquisition cause signal fluctuations, and there is a lack of physical layer anti-motion interference design.

[0006] The applicant has previously filed patents for the basic structure of the photoconductor film and for health monitoring. Building upon these, this invention further optimizes the photoconductor film structure to achieve efficient multi-band acquisition, enhanced signal-to-noise ratio, anti-interference capabilities, and skin color adaptation, providing a high-quality signal source for health monitoring. Summary of the Invention

[0007] (I) Purpose of the Invention The purpose of this invention is to provide a multi-band spectral acquisition and signal enhancement structure based on photoconductive film. By optimizing the grating period, band selection, optical path design, and anti-interference structure, it can achieve high signal-to-noise ratio acquisition of multi-band spectral signals of human skin, and solve the problem of poor signal quality of existing photoconductive films in weak light environment, skin color difference, and motion interference.

[0008] (II) Technical Solution 1. A multi-band spectral acquisition and signal enhancement structure based on a photoconductor film, characterized in that it comprises: a multi-layer grating array disposed on the bottom layer of the photoconductor film, consisting of multiple grating regions with different periods, corresponding to optimized coupling of different bands, including a visible light band grating region and a near-infrared band grating region; an optical path separation structure for separating and transmitting optical signals of different bands to different optical sensors to avoid crosstalk between bands; an anti-ambient light interference layer disposed on the surface of the photoconductor film, using a narrow-band filter film, allowing only specific bands of light to pass through, and attenuating ambient light interference; a skin color adaptive structure composed of multiple gratings of different depths for acquiring reflected light signals at different skin depths; a motion artifact suppression structure using a multi-point acquisition array, acquiring multiple spatially redundant optical signals simultaneously through multiple sensors; and a temperature compensation structure including a temperature sensor and a thermal expansion compensation layer integrated at the edge of the photoconductor film for correcting the influence of ambient temperature changes on the optical properties of the photoconductor film.

[0009] 2. The structure according to claim 1, characterized in that the multilayer grating array is arranged in a side-by-side partitioned manner, with each grating region arranged in band order at different positions on the photoconductive film, each region being 5mm × 5mm in size, and isolation grooves set between regions at 1mm intervals; the visible light band grating region includes green light band gratings and red light band gratings; the near-infrared band grating region includes near-infrared I band gratings and near-infrared II band gratings; the period of each grating is set to 0.6-1.0 times the corresponding center wavelength to meet the phase matching condition; each grating region adopts a gradual period design, with the smallest period in the central region and the largest period at the edge, expanding the effective acquisition angle; microstructure isolation grooves are set between each grating region to prevent lateral crosstalk of the optical signal.

[0010] 3. The structure according to claim 1, characterized in that the optical path separation structure includes a wavelength beam splitter, a plurality of optical sensor arrays and a narrowband filter disposed in front of each sensor, and a microstructure isolation groove disposed between each grating region; under standard test conditions, each band signal is independently transmitted to the corresponding sensor, and the crosstalk rate is ≤5%.

[0011] 4. The structure according to claim 1, characterized in that the anti-ambient light interference layer comprises a multilayer dielectric film and a polarization filter layer, and is synchronously detected in conjunction with the pulse modulation of the terminal screen light source; under standard illumination conditions, the ambient light attenuation is ≥90%.

[0012] 5. The structure according to claim 1, characterized in that the skin color adaptive structure includes multiple gratings of different depths for collecting reflected light signals from the epidermis, dermis, and subcutaneous tissue, and outputting multi-depth spectral data for skin color correction.

[0013] 6. The structure according to claim 1, wherein the motion artifact suppression structure comprises a multi-point acquisition array and an adjacent sensor arrangement structure, for outputting multiple spatially redundant optical signals for use by the motion artifact elimination algorithm.

[0014] 7. The structure according to claim 1, characterized in that, in the temperature compensation structure, the thermal expansion compensation layer is made of a material with a low coefficient of thermal expansion, and the temperature sensor monitors the ambient temperature in real time and outputs temperature data for signal correction.

[0015] 8. A multi-band spectral acquisition and signal enhancement method based on a photoconductor film, applied to the structure described in any one of claims 1-7, characterized by comprising the following steps: S1: Multi-band composite light emitted from the terminal screen is coupled to the user's skin via a multi-layer grating array of the photoconductor film; S2: Reflected light from the skin is acquired via the photoconductor film, and the optical path separation structure separates the light signals of different bands; S3: An anti-ambient light interference layer filters out ambient light, retaining only the signal synchronized with the light source modulation; S4: A multi-point acquisition array simultaneously acquires reflected light signals from multiple locations; S5: A skin color index is calculated based on the shallow grating signal, and the acquisition gain is adjusted; for dark skin, the brightness of the screen light source is automatically increased and the acquisition time is extended, while for light skin, the brightness is reduced and the acquisition time is shortened; S6: The direction of motion is detected, and a weight reduction coefficient is determined based on the motion speed, and the array signal is weighted and fused, with the sensor weights in the direction of motion reduced and the weights in the non-motion direction maintained; S7: The signal strength is corrected based on the ambient temperature; S8: High signal-to-noise ratio multi-band spectral data is output for use in health monitoring applications.

[0016] 9. The method according to claim 8, wherein in step S6, the weight reduction coefficient is calculated based on the motion speed: when the motion speed v < 1 mm / s, the weight is reduced to 0.8 times; when 1 ≤ v < 3 mm / s, it is reduced to 0.5 times; when v ≥ 3 mm / s, it is reduced to 0.2 times; the signal-to-noise ratio of the fused signal is improved by 3-5 times compared with that of single-point acquisition.

[0017] 10. A photoconductive film, characterized in that it comprises the structure described in any one of claims 1-7, for multi-band spectral acquisition and signal enhancement. Detailed Implementation

[0018] The core innovation of this invention lies in the multi-dimensional optimization of the photoconductor film structure to achieve efficient multi-band acquisition and signal enhancement.

[0019] The multi-layer grating array design employs a side-by-side, partitioned arrangement. Each grating region is arranged sequentially according to wavelength within a different position on the photoconductor film. Each region measures 5mm x 5mm, with 1mm spacing between regions via isolation grooves. When a user places their finger, it covers multiple regions. The system uses sensors to identify the signal strength of each region and automatically selects the region with the optimal signal for acquisition, eliminating the need for precise user positioning.

[0020] The bottom layer of the photoconductive film is equipped with a multi-layer grating array, optimized by band partitioning. The period of each grating is set to 0.6-1.0 times the corresponding center wavelength to meet the phase matching condition and achieve efficient coupling: Band Center Wavelength Grating Period Range Grating Depth Target Coupling Efficiency Green Light 550nm 330-550nm 100-150nm ≥85% Red Light 670nm 400-670nm 120-180nm ≥80% Near Infrared I 875nm 525-875nm 150-220nm ≥75% Near Infrared II 1050nm 630-1050nm 180-250nm ≥70% Each grating area adopts a gradient period design, with the smallest period in the central area and the largest period at the edge, expanding the effective acquisition angle so that users can obtain a stable signal without precise finger positioning.

[0021] The optical path separation structure incorporates a wavelength-splitting film (TiO2 / SiO2 multilayer film) within the photoconductive film to separate reflection and transmission at different wavelengths. Narrow-band filters corresponding to the respective wavelengths are placed in front of each sensor (green filter: center wavelength 550nm, bandwidth ±20nm; red filter: center wavelength 670nm, bandwidth ±20nm; near-infrared filter: center wavelength 875nm / 1050nm, bandwidth ±30nm). Microstructured isolation trenches, with a depth ≥ twice the grating depth (e.g., 300nm depth for the green region), are placed between grating areas to prevent lateral crosstalk of the optical signals. Under standard testing conditions, signals of each wavelength are transmitted independently to their corresponding sensors, with a crosstalk rate ≤5%.

[0022] The surface of the anti-ambient light interference layer photoconductive film is coated with multiple dielectric films (TiO2 / SiO2 alternately stacked, a total of 5 layers), with the center wavelength corresponding to the acquisition band. The polarization filter layer only allows light with a specific polarization direction to pass through, further attenuating unpolarized ambient light. Combined with the pulse modulation (frequency 1kHz) of the terminal screen light source, the signal acquisition module only acquires signals synchronized with the modulation frequency. Under standard illumination conditions (10000 lux), ambient light attenuation is ≥90%.

[0023] The skin-adaptive structure uses multiple gratings at different depths (100nm for the shallow layer, 200nm for the middle layer, and 300nm for the deep layer) at the same location to collect reflected light signals from the epidermis, dermis, and subcutaneous tissue, respectively, outputting multi-depth spectral data for skin color correction. The skin color correction algorithm calculates the skin color index (SI = green reflectance / red reflectance) based on the signal intensity collected by the shallow gratings. For dark skin tones (SI < 0.7), it automatically increases the screen light source brightness by 20-50% (adjusted linearly according to the SI value; the lower the SI, the higher the brightness), while extending the acquisition time by 1.5-2 times. For light skin tones (SI > 0.9), it reduces brightness by 20-30% and shortens the acquisition time to 0.7 times to reduce power consumption.

[0024] The motion artifact suppression structure consists of a 5×5 sensor array mounted on the photoconductor film. Each sensor independently acquires data, outputting multiple spatially redundant optical signals for use by the motion artifact elimination algorithm. The motion detection algorithm detects the direction and speed of finger movement by comparing the time and amplitude differences of signals from adjacent sensors. The signal fusion algorithm performs weighted fusion of the array signals: the weight reduction factor is calculated based on the motion speed: • When the motion speed v < 1 mm / s, the weight is reduced to 0.8 times; • When 1 ≤ v < 3 mm / s, it is reduced to 0.5 times; • When v ≥ 3 mm / s, it is reduced to 0.2 times.

[0025] The weight for non-motion directions remains at 1.0. Redundancy check: When a sensor signal is abnormal (signal-to-noise ratio below the threshold), it automatically switches to an adjacent sensor to ensure continuous acquisition. The signal-to-noise ratio of the fused signal is 3-5 times higher than that of single-point acquisition.

[0026] The temperature compensation structure integrates a temperature sensor at the edge of the photoconductor film, monitoring the ambient temperature in real time (accuracy ±0.5℃) and outputting temperature data for signal correction. The thermal expansion compensation layer uses a low thermal expansion coefficient material (polyimide, thermal expansion coefficient approximately 20×10⁻). 6 / K, after modification, can be reduced to 5×10⁻ 6 / K). The temperature correction factor is 0.5% / ℃, derived from fitting test data of the thermal expansion coefficient of polyimide material and the temperature characteristics of grating coupling efficiency. When the temperature deviates from 25℃, a correction factor of 0.5% per ℃ is applied to compensate for the change in coupling efficiency. After testing in a temperature range of -20℃ to 70℃, the corrected coupling efficiency fluctuation is ≤5%.

[0027] The following provides a detailed description of each embodiment: Embodiment 1: Multi-band grating optimization—For blood pressure monitoring, user Zhang uses a photoconductive film to measure blood pressure, requiring simultaneous acquisition of green light (pulse wave) and red light (deep pulse wave). A multi-layer grating array is arranged side-by-side in partitions. Zhang's finger covers multiple grating areas, and the system automatically selects the optimal signal area. The period of the green light area is set to 550nm × 0.6 = 330nm, and the period of the red light area is set to 670nm × 0.6 = 402nm. After optimization, the coupling efficiency of green light is 86%, and that of red light is 82%. The optical path separation structure transmits the green and red light signals to their respective photoelectric sensors, with a crosstalk rate of 3.5%. An anti-ambient light interference layer filters out ambient light, improving the signal-to-noise ratio by 2.8 times compared to the unoptimized structure. With Zhang's finger lightly touching the screen, a high-quality pulse wave signal is obtained, increasing the blood pressure measurement accuracy to over 95%.

[0028] Example 2: Skin Tone Adaptation – Blood Oxygen Monitoring for Dark-Skinned Individuals. User Li has dark skin (SI=0.65). When using traditional photoconductive films to measure blood oxygen, the red light signal is weak, resulting in a low signal-to-noise ratio. The skin tone adaptive structure of this invention detects SI<0.7 and automatically increases the screen light source brightness by 30% (linearly adjusted according to the SI value), while simultaneously extending the acquisition time by 1.5 times. The intensity of the acquired red and infrared light signals is increased by 2 times, the signal-to-noise ratio is increased by 4 times, and the accuracy of blood oxygen measurement is increased from 85% to 94%.

[0029] Example 3: Motion Artifact Suppression – Fatigue Driving Monitoring. Driver Wang made slight hand movements while driving, and the pulse wave signal acquired by traditional single-point acquisition was severely affected by motion interference. This invention uses a 5×5 sensor array for real-time acquisition. The motion detection algorithm detected a finger moving to the right at a speed v=2mm / s. The weight reduction factor was set to 0.5 times, reducing the weight of the right sensor to 0.5 times while maintaining the weight of the left sensor at 1.0 times. After signal fusion, motion artifacts were attenuated by 85%, and the accuracy of heart rate extraction improved from 78% to 96%.

[0030] Example 4: Ambient Light Interference Resistance – Outdoor Use Scenario: User Zhao measured his heart rate using a photoconductive film under strong outdoor light (10000 lux). The multi-layered dielectric film of the ambient light interference resistance layer attenuated ambient light by 90%, and the polarization filter layer further attenuated unpolarized light. The screen light source was pulse-modulated at a frequency of 1kHz, and the signal acquisition module only acquired the synchronization signal. Ultimately, ambient light interference was attenuated by 95%, the signal-to-noise ratio was improved by 5 times in the unoptimized structure, and the heart rate measurement accuracy remained above 92%.

[0031] Example 5: Temperature Compensation – User Sun used the photoconductive film in a -10℃ environment. The temperature sensor detected an ambient temperature of -10℃, with a temperature correction coefficient of 0.5% / ℃. After compensation, the coupling efficiency recovered to 95% of that at room temperature. The thermal expansion compensation layer uses a material with a low coefficient of thermal expansion, resulting in a grating period change rate of <0.1% and a 3-fold improvement in signal stability. Anomaly Handling Mechanism

[0032] 1. Grating Area Failure Handling: When the coupling efficiency of a grating area in a certain band is lower than 50%, the system automatically switches to an adjacent grating area and sends a notification: "Some grating areas are abnormal; please clean the photoconductor film." 2. Ambient Light Excess Handling: When the ambient light intensity exceeds 10,000 lux, the system automatically switches to near-infrared band acquisition (where the near-infrared component is low) to ensure basic monitoring functions are available.

[0033] 3. Handling excessive movement: When the detected finger movement speed exceeds 5mm / s, the system pauses data collection and sends a notification: "Please keep your finger stable." 4. Handling excessive temperature: When the ambient temperature is below -20℃ or above 70℃, the system displays the message: "Ambient temperature exceeds the operating range; measurement results may be inaccurate." Beneficial effects

[0034] 1. Multi-band optimization: The multi-layer grating array optimizes the period and depth for green light, red light, near-infrared I, and near-infrared II, respectively, with coupling efficiency of ≥70-85% for each band, an improvement of 30-50% compared to a single grating; 2. Optical path separation: Wavelength beam splitter + narrowband filter + isolation slot, crosstalk rate between bands ≤5%, significantly improving signal purity; 3. Resistance to ambient light interference: Multi-layer dielectric film + polarization filter + synchronized light source modulation, ambient light attenuation ≥90%, still able to work normally under strong outdoor light; 4. Skin color adaptation: Multi-depth grating collects signals from different skin layers, and the skin color index automatically adjusts the gain, improving the measurement accuracy of dark skin people to 94%; 5. Motion artifact suppression: 5×5 sensor array + motion speed weighted, motion artifact attenuation 85%, signal-to-noise ratio improved by 3-5 times; 6. Temperature compensation: Temperature sensor + low thermal expansion material + correction coefficient 0.5% / ℃, signal stability improved by 3 times in the range of -20℃~70℃; 7. Redundant design: The multi-point acquisition array supports sensor failure switching to ensure continuous acquisition; 8. Technological synergy: This structure provides a high-quality signal source for health monitoring patents such as blood pressure, blood oxygen, blood glucose, heart rate variability, and arteriosclerosis, and is the core infrastructure for photoconductive film health monitoring.

Claims

1. A multi-band spectral acquisition and signal enhancement structure based on a photoconductive film, characterized in that, include: A multi-layer grating array, located at the bottom of the photoconductor film, consists of multiple grating regions with different periods, each corresponding to optimized coupling for different wavelength bands, including grating regions for the visible light band and grating regions for the near-infrared band. An optical path separation structure separates and transmits optical signals of different wavelength bands to different optical sensors, avoiding crosstalk between bands. An anti-ambient light interference layer, located on the surface of the photoconductor film, uses a narrow-band filter film to allow only specific wavelengths of light to pass through, attenuating ambient light interference. A skin-tone adaptive structure, composed of multiple gratings at different depths, is used to collect reflected light signals from different skin depths. The motion artifact suppression structure employs a multi-point acquisition array, simultaneously acquiring data from multiple sensors and outputting multiple spatially redundant optical signals. The temperature compensation structure includes a temperature sensor integrated into the edge of the photoconductor film and a thermal expansion compensation layer, used to correct the influence of ambient temperature changes on the optical properties of the photoconductor film.

2. The structure according to claim 1, characterized in that, The multilayer grating array is arranged in a side-by-side partitioned manner, with each grating region arranged in band order at different positions on the photoconductive film. Each region is 5mm × 5mm in size, and isolation grooves are set between regions at 1mm intervals. The visible light band grating region includes green light band gratings and red light band gratings; the near-infrared band grating region includes near-infrared I band gratings and near-infrared II band gratings. The period of each grating is set to 0.6-1.0 times the corresponding center wavelength to meet the phase matching condition. Each grating region adopts a gradient period design, with the smallest period in the central region and the largest period at the edge, expanding the effective acquisition angle. Microstructure isolation grooves are set between each grating region to prevent lateral crosstalk of the optical signal.

3. The structure according to claim 1, characterized in that, The optical path separation structure includes a wavelength splitting film, multiple optical sensor arrays and narrowband filters placed in front of each sensor, as well as microstructure isolation grooves placed between each grating region; under standard test conditions, each band signal is independently transmitted to the corresponding sensor, with a crosstalk rate ≤5%.

4. The structure according to claim 1, characterized in that, The anti-ambient light interference layer includes a multilayer dielectric film and a polarization filter layer, and is used in conjunction with the pulse modulation of the terminal screen light source for synchronous detection; under standard lighting conditions, the ambient light attenuation is ≥90%.

5. The structure according to claim 1, characterized in that, The skin color adaptive structure includes multiple gratings of different depths, used to collect reflected light signals from the epidermis, dermis, and subcutaneous tissue, and output multi-depth spectral data for skin color correction.

6. The structure according to claim 1, characterized in that, The motion artifact suppression structure includes a multi-point acquisition array and an adjacent sensor arrangement structure, which is used to output multiple spatially redundant optical signals for use by the motion artifact elimination algorithm.

7. The structure according to claim 1, characterized in that, In the temperature compensation structure, the thermal expansion compensation layer is made of a material with a low coefficient of thermal expansion, and the temperature sensor monitors the ambient temperature in real time and outputs temperature data for signal correction.

8. A multi-band spectral acquisition and signal enhancement method based on a photoconductive film, applied to the structure described in any one of claims 1-7, characterized in that, Includes the following steps: S1: The terminal screen emits multi-band composite light, which is coupled to the user's skin through a multi-layer grating array of the photoconductor film; S2: The skin-reflected light is collected by the photoconductor film, and the optical path separation structure separates the light signals of different bands; S3: The anti-ambient light interference layer filters out ambient light, retaining only the signal that is synchronized with the light source modulation; S4: The multi-point acquisition array simultaneously acquires reflected light signals from multiple locations; S5: The skin color index is calculated based on the shallow grating signal, and the acquisition gain is adjusted; for dark skin, the screen light source brightness is automatically increased and the acquisition time is extended, while for light skin, the brightness is reduced and the acquisition time is shortened; S6: Detect the direction of motion, determine the weight reduction coefficient based on the motion speed, and perform weighted fusion of the array signals. The weight of the sensor in the direction of motion is reduced, while the weight in the non-motion direction is maintained. S7: Corrects signal strength based on ambient temperature; S8: Outputs high signal-to-noise ratio multi-band spectral data for use in health monitoring applications.

9. The method according to claim 8, characterized in that, In step S6, the weight reduction coefficient is calculated based on the motion speed: when the motion speed v < 1 mm / s, the weight is reduced to 0.8 times; when 1 ≤ v < 3 mm / s, it is reduced to 0.5 times; when v ≥ 3 mm / s, it is reduced to 0.2 times; the signal-to-noise ratio of the fused signal is 3-5 times higher than that of single-point acquisition.

10. A photoconductive film, characterized in that, The structure described in any one of claims 1-7 is used for multi-band spectral acquisition and signal enhancement.