Method for quickly judging spectral characteristics of material through near-infrared narrow band

Abstract

The invention discloses a method for quickly judging spectral characteristics of a material through a near-infrared narrow band, which comprises the following steps that: full-spectrum light sequentially passes through at least three groups of different near-infrared narrow-band filters and visible light filters to generate at least three kinds of near-infrared light and visible light with different wavelengths, and the wavelength of the near-infrared light is in a range of 1200-3000nm; at least three kinds of near-infrared light and visible light with different wavelengths are adopted to irradiate the to-be-detected material; reading amplitude signal values of at least three kinds of near-infrared light with different wavelengths reflected by the material to be detected by adopting a near-infrared light sensor; and judging whether the amplitude signal values of the at least three kinds of near-infrared light are in a normal material amplitude set value range or an abnormal material amplitude set value range, and further judging whether the to-be-detected material is a normal material or an abnormal material. The method can quickly judge whether the components of the to-be-detected material are normal or not, further quickly judge the product quality, avoid manual misoperation, remarkably reduce the cost, and is wide in application range and high in upgradability.

Description

Technical Field

[0001] The present invention relates to the field of infrared detection technology, and in particular to a method for quickly judging the spectral characteristics of a material through a near-infrared narrow band. Background Art

[0002] The usual material judgment is to judge the shape, outline, weight, color, etc. This is a comprehensive, multi-dimensional evaluation method that aims to accurately identify and distinguish materials from different angles.

[0003] Shape and outline are one of the most intuitive characteristics of materials. Different materials often have unique shapes and outlines. By observing and measuring the shape and outline of materials, we can preliminarily determine the type, specification and purpose of the materials. For example, in the manufacturing industry, by comparing the shape and outline of the material with the product design drawings or samples, we can determine whether the material meets the production requirements.

[0004] Weight is another important property of materials, which is related to factors such as the material, density and volume of the material. By measuring the weight of materials, the authenticity and quality of the materials can be further verified. In some cases, weight can also be used as a basis for material classification and measurement. For example, in the field of warehousing and logistics, by measuring the weight of materials, inventory, transportation costs and distribution efficiency can be accurately calculated.

[0005] Color is also an important dimension for material judgment. Different materials may have different color characteristics, which can be used as the basis for material identification and classification. For example, in the textile industry, by observing the color of the cloth, you can preliminarily judge its material and purpose; in the food industry, by observing the color of the food, you can judge its freshness and quality.

[0006] In practical applications, material judgment is often not a single-dimensional one, but requires comprehensive consideration of multiple factors. In addition to shape, weight and color, it may also involve material, hardness, toughness, glossiness and other aspects of the material. By comprehensively using a variety of judgment methods and technical means, a comprehensive and accurate judgment of the material can be achieved.

[0007] In the process of implementing the technical method of the embodiment of the present invention, the inventor of this patent has at least found the following technical problems in the prior art: Material judgment sometimes requires testing whether the material composition is abnormal, which cannot be determined by existing weighing and visual inspection methods.

[0008] In summary, the existing material judgment methods are unable to detect abnormal material composition. Summary of the invention

[0009] The embodiment of the present invention provides a method for quickly judging the spectral characteristics of a material through a near-infrared narrow band, which solves the problem that the existing material judgment method cannot detect abnormal material composition.

[0010] The embodiment of the present invention provides a method for quickly judging the spectral characteristics of a material through a near-infrared narrow band, comprising: Passing the full spectrum of light through at least three different sets of near-infrared narrowband filters and visible light filters in sequence to generate at least three different wavelengths of near-infrared light and visible light, wherein the wavelength of the near-infrared light is within the range of 1200nm-3000nm; At least three different wavelengths of near-infrared light and visible light are used to illuminate the material to be tested; A near-infrared light sensor is used to read the amplitude signal values ​​of at least three different wavelengths of near-infrared light reflected by the material to be detected; Determine whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the range of normal material amplitude setting values ​​or determine whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the range of abnormal material amplitude setting values; When the amplitude signal values ​​of at least three near-infrared lights are all within the amplitude setting value range of normal materials, the material to be detected is judged to be a normal material; when the amplitude signal values ​​of at least three near-infrared lights are not within the amplitude setting value range of normal materials, the material to be detected is judged to be an abnormal material; or when the amplitude signal values ​​of at least three near-infrared lights are all within the amplitude setting value range of abnormal materials, the material to be detected is judged to be an abnormal material; and when the amplitude signal values ​​of at least three near-infrared lights are not within the amplitude setting value range of abnormal materials, the material to be detected is judged to be a normal material.

[0011] Optionally, before judging whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the normal material amplitude setting value range, the method further includes: Record the amplitude signal values ​​of at least three types of near-infrared light reflected by normal materials; Selecting the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights; A normal material amplitude setting value range is set based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights.

[0012] Optionally, the setting of the normal material amplitude setting value range based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights specifically includes: Multiply the maximum value of the amplitude signal values ​​of at least three near-infrared lights by 110% to obtain the upper limit value of the normal material amplitude setting value range; The minimum value of the amplitude signal values ​​of at least three kinds of near-infrared light is multiplied by 90% to obtain the lower limit value of the normal material amplitude setting value range.

[0013] Optionally, before judging whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the abnormal material amplitude setting value range, the method further includes: Record the amplitude signal values ​​of at least three types of near-infrared light reflected by the abnormal material; Selecting the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights; The abnormal material amplitude setting value range is set based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights.

[0014] Optionally, the abnormal material amplitude setting value range is set based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights, specifically including: Multiply the maximum value of the amplitude signal values ​​of at least three near-infrared lights by 110% to obtain the upper limit value of the abnormal material amplitude setting value range; The minimum value of the amplitude signal values ​​of at least three kinds of near-infrared light is multiplied by 90% to obtain the lower limit value of the abnormal material amplitude setting value range.

[0015] Optionally, after irradiating the material to be detected with near-infrared light and visible light of at least three different wavelengths, the method further comprises: According to whether the visible light is irradiated on the material to be detected, determining whether at least three near-infrared lights of different wavelengths are irradiated on the material to be detected; When visible light is irradiated on the material to be detected, the judgment result shows that at least three different wavelengths of near-infrared light are irradiated on the material to be detected; and when visible light is not irradiated on the material to be detected, the judgment result shows that at least three different wavelengths of near-infrared light are not irradiated on the material to be detected.

[0016] Optionally, after the judgment result shows that at least three near-infrared lights of different wavelengths are not irradiated on the material to be detected, the method further includes: The positions of at least three different wavelengths of near-infrared light and visible light are adjusted so that the visible light and at least three different wavelengths of near-infrared light are irradiated on the material to be detected.

[0017] Optionally, the at least three near-infrared lights of different wavelengths are specifically near-infrared lights of three wavelengths of 1300 nm, 1800 nm and 1940 nm respectively.

[0018] Optionally, the at least three near-infrared lights of different wavelengths are specifically near-infrared lights of three wavelengths of 1940 nm, 2150 nm and 2320 nm respectively.

[0019] Optionally, the at least three near-infrared lights of different wavelengths are five near-infrared lights of wavelengths of 1300 nm, 1818 nm, 1940 nm, 2150 nm and 2320 nm respectively.

[0020] One or more technical solutions provided in the embodiments of the present invention have at least the following technical effects or advantages: According to the principle that different material components have different near-infrared light absorption rates and reflectance rates, the present invention uses at least three different wavelengths of near-infrared light to irradiate the material to be detected, and the wavelengths are in the range of 1200nm-3000nm. By calculating the energy values ​​of at least three different wavelengths of near-infrared light after reflection, it is possible to quickly determine whether the composition of the material to be detected is normal, and then quickly determine the product quality, avoid manual misoperation, and there is no need to purchase a full-spectrum scanning instrument in the wavelength range of 1200nm-3000nm, which can significantly reduce costs, and can make judgments on moving materials to be detected, with a wide range of applications; special materials can be judged by simply replacing near-infrared light of different wavelengths, and the method has strong upgradeability. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 This is a flow chart of a method for quickly judging the spectral characteristics of a material through a near-infrared narrow band in one embodiment of the present invention; Figure 2 This is a structural diagram of a device for quickly judging the spectral characteristics of a material through a near-infrared narrow band in one embodiment of the present invention; Figure 3 Schematic diagram of amplitude signal values ​​of five different wavelengths of near-infrared light reflected by a material to be detected in one embodiment of the present invention. DETAILED DESCRIPTION

[0022] The embodiment of the present invention provides a method for quickly judging the spectral characteristics of a material through a near-infrared narrow band, which solves the problem that the existing material judgment method cannot detect abnormal material composition.

[0023] In order to better understand the above-mentioned method of quickly judging the spectral characteristics of materials through near-infrared narrow band, the following will be described in detail in conjunction with the drawings and specific implementation methods of the specification. Obviously, the embodiments described in the present invention are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0024] like Figure 2 As shown, the embodiment of the present invention implements a method for quickly judging the spectral characteristics of a material through a near-infrared narrow band through a device for quickly judging the spectral characteristics of a material through a near-infrared narrow band.

[0025] The working principle of the device is as follows: the full spectrum light emitted by the light source 401 is converged by the first convex lens 402 and projected onto the filter 405 on the filter disc 403 to filter out stray light and generate near-infrared light and visible light, and then converged by the second convex lens 406, and then irradiated onto the material to be detected 408 through a 45-degree reflector 407. After the material to be detected 408 absorbs part of the near-infrared light, the reflected light passes through a spherical reflector 409 and reaches the near-infrared light sensor 410. Among them, the motor 404 is used to switch the filter 405 on the filter disc 403. For example: the filter disc is installed with narrow-band infrared filters and visible light filters with wavelengths of 1300nm, 1818nm, 1940nm, 2150nm, and 2320nm in sequence, and the motor drives the filter disc to rotate at 4000rpm. After passing through the narrow-band filter, the full-spectrum light is divided into near-infrared light and visible light with wavelengths of 1300nm, 1818nm, 1940nm, 2150nm, and 2320nm. The near-infrared light sensor reads the amplitude signal values ​​of five wavelengths of near-infrared light, and can complete 66 samplings per second, realizing material composition judgment within 0.2S, and can cope with high-speed detection and judgment on the assembly line. In addition, the corresponding near-infrared light wavelength is optimized according to the peaks and valleys absorbed by the material within the near-infrared spectrum. The device only needs to replace the corresponding narrow-band filter, without changing the circuit and optical path, and has strong upgradeability.

[0026] The device can identify materials in motion. For example, the device stores spectral characteristics of five wavelengths of near-infrared light of bran or flour, and determines whether the material to be detected is bran or flour based on the near-infrared spectral characteristics reflected by the material to be detected and the pre-stored near-infrared spectral characteristics of bran or flour.

[0027] The device can judge foreign objects in motion. For example, the device can store the spectral characteristics of near-infrared light of foreign objects. When the reflected near-infrared spectral characteristics meet the pre-stored near-infrared spectral characteristics of foreign objects, the material to be detected is a foreign object. The device can also store the spectral characteristics of near-infrared light of normal materials. When the reflected near-infrared spectral characteristics do not meet the pre-stored near-infrared spectral characteristics of normal materials, the material to be detected is a foreign object.

[0028] Laboratory case: After learning the near-infrared spectral characteristics of flour, a plate of flour was mixed into multiple plates of lime. It was difficult to distinguish which plate contained flour by appearance and color. These plates were placed under the device respectively. The device was able to quickly distinguish which plate contained flour based on the near-infrared spectral characteristics of the flour.

[0029] In the automated control of assembly lines, it is often necessary to identify the type of material before subsequent automatic control can be performed according to the process. For example, in the production of dried noodles, various flours (high-gluten flour, medium-gluten flour, low-gluten flour) and bran may be transported in the same pipeline. The device of the present invention can quickly identify the transported materials to avoid manual misoperation.

[0030] In the chemical production process, before feeding, the device of the present invention can be used to determine whether the compound meets the corresponding chemical composition, thereby avoiding incorrect feeding; by determining whether the finished product meets the corresponding near-infrared spectral characteristics, the product quality can be determined.

[0031] Other important ingredient production lines are used to check whether raw materials and finished products meet the corresponding near-infrared spectral characteristics, quickly judge product quality, and quickly produce early warnings.

[0032] During the process of dipping or coating, the amount of glue can be measured, and by learning the near-infrared spectral characteristics of qualified products after coating, an alarm can also be issued if the glue formula is abnormal.

[0033] Please refer to the following Figure 1 A method for quickly judging the spectral characteristics of a material through a near-infrared narrow band includes steps 10, 20, 30, 40 and 50.

[0034] Step 10: Passing the full spectrum light through at least three different groups of near-infrared narrowband filters and visible light filters in sequence to generate at least three different wavelengths of near-infrared light and visible light, and the wavelength of the near-infrared light is in the range of 1200nm-3000nm.

[0035] In the specific implementation process of step 10, for example: a halogen lamp is used as a light source, the light source emits full-spectrum light, the full-spectrum light passes through at least three groups of different near-infrared narrow-band filters in sequence to generate at least three different wavelengths of near-infrared light, and the wavelength of the near-infrared light is in the range of 1200nm-3000nm, the full-spectrum light passes through a visible light filter to generate visible light, and the generated at least three different wavelengths of near-infrared light and visible light are used in subsequent steps.

[0036] Step 20: Use near-infrared light and visible light of at least three different wavelengths to irradiate the material to be tested.

[0037] Since different material components have different near-infrared light absorption and reflectivity, at least three different wavelengths of near-infrared light are used to irradiate the material to be detected. By calculating the energy values ​​of at least three different wavelengths of near-infrared light after reflection, it can be used to determine whether the material components to be detected are normal. Within the spectral range of near-infrared light, the frequency doubling and combined frequency absorption of the vibration of hydrogen-containing groups in the material components are used to analyze the near-infrared characteristics of specific wavelengths for material judgment. In the near-infrared spectrum, the first-order frequency doubling and combined frequency base of the vibration of hydrogen groups CH, hydrogen groups OH, and hydrogen groups NH are between 1200nm-3000nm, and the absorption peaks and valleys in this range are most obvious, but the full-spectrum scanning instrument within this wavelength range is expensive, and the full-spectrum scanning measurement speed is relatively slow. Therefore, the present invention uses at least three near-infrared narrow-band filters in combination with near-infrared light sensors to achieve material component judgment within 0.2S.

[0038] Among them, different numbers of near-infrared lights of different wavelengths are selected according to different materials to be detected, that is, near-infrared lights of corresponding wavelengths are selected according to the characteristics of the material components. For example: when the customer only detects the moisture in the material, at least three near-infrared lights of different wavelengths are specifically three near-infrared lights with wavelengths of 1300nm, 1800nm ​​and 1940nm. For another example: when the customer detects the components of the material, at least three near-infrared lights of different wavelengths are specifically three near-infrared lights with wavelengths of 1940nm, 2150nm and 2320nm, which correspond to the molecular bonds of most organic substances. For another example: when the customer needs to accurately detect the components of the material, at least three near-infrared lights of different wavelengths are specifically five near-infrared lights with wavelengths of 1300nm, 1818nm, 1940nm, 2150nm and 2320nm. Near-infrared light with a wavelength of 1940nm corresponds to the absorption peak of the hydrogen group OH, near-infrared light with a wavelength of 2150nm corresponds to the absorption peak of the NH hydrogen group, near-infrared light with a wavelength of 2320nm corresponds to the absorption peak of the hydrogen group CH, and near-infrared light with wavelengths of 1300nm and 1818nm corresponds to the near-infrared absorption valley.

[0039] In the specific implementation process of step 20, for example, at least three kinds of near-infrared light and visible light are irradiated on the material to be detected through the optical elements (first convex lens, filter, second convex lens, 45-degree reflector) in the device. Among them, the near-infrared light is used to detect the material, and the visible light is used to detect whether the near-infrared light is irradiated on the material to be detected.

[0040] Since the naked eye can identify visible light but cannot identify near-infrared light, in order to facilitate the detection of whether near-infrared light is irradiated on the material to be detected, the present invention irradiates visible light and near-infrared light on the material to be detected to detect whether the near-infrared light is offset. After step 20 uses at least three different wavelengths of near-infrared light and visible light to irradiate the material to be detected, it also includes: judging whether at least three different wavelengths of near-infrared light are irradiated on the material to be detected based on whether the visible light is irradiated on the material to be detected; when the visible light is irradiated on the material to be detected, the judgment result shows that at least three different wavelengths of near-infrared light are irradiated on the material to be detected; and when the visible light is not irradiated on the material to be detected, the judgment result shows that at least three different wavelengths of near-infrared light are not irradiated on the material to be detected.

[0041] After the judgment result shows that the near-infrared light of at least three different wavelengths is not irradiated on the material to be detected, it also includes: adjusting the positions of the near-infrared light of at least three different wavelengths and the visible light to allow the visible light and the near-infrared light of at least three different wavelengths to irradiate the material to be detected.

[0042] In the specific implementation process, for example: by changing the position of the light source, the first convex lens, the second convex lens or the 45-degree reflector in the device, the position of at least three different wavelengths of near-infrared light and visible light is adjusted so that visible light and at least three different wavelengths of near-infrared light can be irradiated on the material to be detected.

[0043] Step 30: Use a near-infrared light sensor to read the amplitude signal values ​​of at least three different wavelengths of near-infrared light reflected by the material to be detected.

[0044] In the specific implementation process of step 30, for example: near-infrared light is irradiated onto the material to be detected, part of the near-infrared light is absorbed by the material to be detected, and part of the near-infrared light is reflected by the material to be detected. The reflected near-infrared light is irradiated to the near-infrared light sensor through a spherical reflector. After the near-infrared light sensor senses the near-infrared light, it is calculated and processed to read the amplitude signal values ​​of at least three different wavelengths of near-infrared light reflected by the material to be detected.

[0045] Step 40: Determine whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the range of normal material amplitude setting values ​​or determine whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the range of abnormal material amplitude setting values.

[0046] In the specific implementation process of step 40, for example, the amplitude signal values ​​of at least three near-infrared lights read are compared with the pre-stored normal material amplitude setting value range or abnormal material amplitude setting value range, and it is determined whether the amplitude signal values ​​of at least three near-infrared lights are within the normal material amplitude setting value range, or whether the amplitude signal values ​​of at least three near-infrared lights are within the abnormal material amplitude setting value range.

[0047] Before determining in step 40 whether the amplitude signal values ​​of at least three near-infrared lights are within the normal material amplitude setting value range, the method also includes: recording the amplitude signal values ​​of at least three near-infrared lights reflected by normal materials; selecting the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights; and setting the normal material amplitude setting value range based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights.

[0048] In the specific implementation process, for example: five kinds of near-infrared light with wavelengths of 1300nm, 1818nm, 1940nm, 2150nm, and 2320nm are used to continuously monitor the amplitude of the near-infrared light reflected by the flour on the conveyor belt, and the maximum and minimum values ​​of the amplitude of the near-infrared light of the corresponding wavelength are recorded to obtain the following table data: Serial number wavelength Maximum value of amplitude signal value ( MAX ） Minimum amplitude signal value ( MIN ） ① 1300nm 109604 108217 ② 1818nm 84167 82956 ③ 1940nm 78611 76540 ④ 2150nm 65550 64825 ⑤ 2320nm 54320 52100 The maximum value of the amplitude signal values ​​of the five types of near-infrared light can be directly used as the upper limit of the normal material amplitude setting value range, and the minimum value of the amplitude signal values ​​of the five types of near-infrared light can be used as the lower limit of the normal material amplitude setting value range. Taking the near-infrared light with a wavelength of 1300nm as an example, the normal material amplitude range is 108217-109604.

[0049] Considering that the material to be detected is in an assembly line environment, external factors may cause the maximum and minimum values ​​of the near-infrared light amplitude to change by a certain proportion, so the present invention sets a corresponding deviation ratio to set a reasonable normal material amplitude setting value range. The above-mentioned step of setting the normal material amplitude setting value range based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights specifically includes: multiplying the maximum value of the amplitude signal values ​​of at least three near-infrared lights by 110% to obtain the upper limit value of the normal material amplitude setting value range; multiplying the minimum value of the amplitude signal values ​​of at least three near-infrared lights by 90% to obtain the lower limit value of the normal material amplitude setting value range.

[0050] It should be noted that different deviation values ​​can be set according to actual needs. For example, the maximum value of the amplitude signal value of at least three near-infrared lights can be multiplied by 105%, 108%, 115%, etc., and the minimum value of the amplitude signal value of at least three near-infrared lights can be multiplied by 88%, 95%, 96%, etc., which is not limited to the present invention.

[0051] In the specific implementation process, for example: after recording the maximum and minimum values ​​of the amplitude of near-infrared light with five wavelengths of 1300nm, 1818nm, 1940nm, 2150nm, and 2320nm, the deviation ratio is set to 10%, the maximum value of the amplitude signal value is multiplied by 110%, and then the minimum value of the amplitude signal is multiplied by 90%, and the following data is obtained.

[0052]

[0053] Multiply the maximum value of the amplitude signal value of the five kinds of near-infrared light by 110% as the upper limit of the normal material amplitude setting value range, and multiply the minimum value of the amplitude signal value of the five kinds of near-infrared light by 90% as the lower limit of the normal material amplitude setting value range. For near-infrared light with a wavelength of 1300nm, the normal material amplitude range is 97395-120564.

[0054] Before determining whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the abnormal material amplitude setting value range in step 40, the method further includes: recording the amplitude signal values ​​of at least three kinds of near-infrared light reflected by the abnormal material; selecting the maximum and minimum values ​​of the amplitude signal values ​​of at least three kinds of near-infrared light; and setting the abnormal material amplitude setting value range based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three kinds of near-infrared light. Since the above steps are similar to the steps of setting the normal material amplitude setting value range, they will not be described in detail.

[0055] Based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights, the amplitude setting value range of abnormal materials is set, specifically including: multiplying the maximum value of the amplitude signal values ​​of at least three near-infrared lights by 110% to obtain the upper limit value of the amplitude setting value range of abnormal materials; multiplying the minimum value of the amplitude signal values ​​of at least three near-infrared lights by 90% to obtain the lower limit value of the amplitude setting value range of abnormal materials. Since the above steps are similar to the steps of setting the upper and lower limits of the amplitude setting value range of normal materials, they will not be repeated. It should be noted that different deviation values ​​can be set according to actual needs. For example, the maximum value of the amplitude signal values ​​of at least three near-infrared lights can be multiplied by 105%, 108%, 115%, etc., and the minimum value of the amplitude signal values ​​of at least three near-infrared lights can be multiplied by 88%, 95%, 96%, etc., which are not limited by the present invention.

[0056] Step 50: When the amplitude signal values ​​of at least three near-infrared lights are all within the amplitude setting value range of normal materials, the material to be detected is judged to be a normal material; when the amplitude signal values ​​of at least three near-infrared lights are not within the amplitude setting value range of normal materials, the material to be detected is judged to be an abnormal material; or when the amplitude signal values ​​of at least three near-infrared lights are all within the amplitude setting value range of abnormal materials, the material to be detected is judged to be an abnormal material; and when the amplitude signal values ​​of at least three near-infrared lights are not within the amplitude setting value range of abnormal materials, the material to be detected is judged to be a normal material.

[0057] In the specific implementation process of step 50, for example, by judging whether the amplitude signal values ​​of at least three near-infrared lights are within the normal material amplitude setting value range or by judging whether the amplitude signal values ​​of at least three near-infrared lights are within the abnormal material amplitude setting value range, it is judged whether the material to be detected is a normal material or an abnormal material. If by judging whether the amplitude signal values ​​of at least three near-infrared lights are within the normal material amplitude setting value range, when the generated first judgment result shows that the amplitude signal values ​​of at least three near-infrared lights are all within the normal material amplitude setting value range, then the material to be detected is judged to be a normal material; and when the generated first judgment result shows that the amplitude signal values ​​of at least three near-infrared lights are not within the normal material amplitude setting value range, then the material to be detected is judged to be an abnormal material. If it is judged whether the amplitude signal values ​​of at least three kinds of near-infrared lights are within the range of the amplitude setting values ​​of abnormal materials, when the generated second judgment result indicates that the amplitude signal values ​​of at least three kinds of near-infrared lights are all within the range of the amplitude setting values ​​of abnormal materials, then the material to be detected is judged to be an abnormal material; and when the generated second judgment result indicates that the amplitude signal values ​​of at least three kinds of near-infrared lights are not within the range of the amplitude setting values ​​of abnormal materials, then the material to be detected is judged to be a normal material.

[0058] like Figure 3 As shown in the figure, the red line corresponds to the upper limit of the normal material amplitude setting value range, the blue line corresponds to the lower limit of the normal material amplitude setting value range, and the black line corresponds to the amplitude signal value of the read near-infrared light. Since the black line is within the range of the red line and the black line, it can be determined that the material to be detected is a normal material.

[0059] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A method for quickly judging the spectral characteristics of materials through near-infrared narrow band, It is characterized in that include: Passing the full spectrum of light through at least three different sets of near-infrared narrowband filters and visible light filters in sequence to generate at least three different wavelengths of near-infrared light and visible light, wherein the wavelength of the near-infrared light is within the range of 1200nm-3000nm; At least three different wavelengths of near-infrared light and visible light are used to illuminate the material to be tested; A near-infrared light sensor is used to read the amplitude signal values ​​of at least three different wavelengths of near-infrared light reflected by the material to be detected; Determine whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the range of normal material amplitude setting values ​​or determine whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the range of abnormal material amplitude setting values; When the amplitude signal values ​​of at least three near-infrared lights are all within the amplitude setting value range of normal materials, the material to be detected is judged to be a normal material; when the amplitude signal values ​​of at least three near-infrared lights are not within the amplitude setting value range of normal materials, the material to be detected is judged to be an abnormal material; or when the amplitude signal values ​​of at least three near-infrared lights are all within the amplitude setting value range of abnormal materials, the material to be detected is judged to be an abnormal material; and when the amplitude signal values ​​of at least three near-infrared lights are not within the amplitude setting value range of abnormal materials, the material to be detected is judged to be a normal material.

2. The method according to claim 1, It is characterized in that Before determining whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the normal material amplitude setting value range, the method further includes: Record the amplitude signal values ​​of at least three types of near-infrared light reflected by normal materials; Selecting the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights; A normal material amplitude setting value range is set based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights.

3. The method according to claim 2, It is characterized in that The setting of the normal material amplitude setting value range based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights specifically includes: Multiply the maximum value of the amplitude signal values ​​of at least three near-infrared lights by 110% to obtain the upper limit value of the normal material amplitude setting value range; The minimum value of the amplitude signal values ​​of at least three kinds of near-infrared light is multiplied by 90% to obtain the lower limit value of the normal material amplitude setting value range.

4. The method according to claim 1, It is characterized in that Before determining whether the amplitude signal values ​​of at least three kinds of near-infrared light are within the abnormal material amplitude setting value range, the method further includes: Record the amplitude signal values ​​of at least three types of near-infrared light reflected by the abnormal material; Selecting the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights; The abnormal material amplitude setting value range is set based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights.

5. The method according to claim 4, It is characterized in that Based on the maximum and minimum values ​​of the amplitude signal values ​​of at least three near-infrared lights, the amplitude setting value range of abnormal materials is set, specifically including: Multiply the maximum value of the amplitude signal values ​​of at least three near-infrared lights by 110% to obtain the upper limit value of the abnormal material amplitude setting value range; The minimum value of the amplitude signal values ​​of at least three kinds of near-infrared light is multiplied by 90% to obtain the lower limit value of the abnormal material amplitude setting value range.

6. The method according to claim 1, It is characterized in that After the method of irradiating the material to be detected with near-infrared light and visible light of at least three different wavelengths, the method further comprises: According to whether the visible light is irradiated on the material to be detected, determining whether at least three near-infrared lights of different wavelengths are irradiated on the material to be detected; When visible light is irradiated on the material to be detected, the judgment result shows that at least three different wavelengths of near-infrared light are irradiated on the material to be detected; and when visible light is not irradiated on the material to be detected, the judgment result shows that at least three different wavelengths of near-infrared light are not irradiated on the material to be detected.

7. The method according to claim 6, It is characterized in that After the judgment result shows that at least three different wavelengths of near-infrared light are not irradiated on the material to be detected, the method further includes: The positions of at least three different wavelengths of near-infrared light and visible light are adjusted so that the visible light and at least three different wavelengths of near-infrared light are irradiated on the material to be detected.

8. The method according to claim 1, It is characterized in that The at least three near-infrared lights of different wavelengths are specifically near-infrared lights of three wavelengths of 1300 nm, 1800 nm and 1940 nm respectively.

9. The method according to claim 1, It is characterized in that The at least three near-infrared lights of different wavelengths are specifically near-infrared lights of three wavelengths of 1940 nm, 2150 nm and 2320 nm respectively.

10. The method according to claim 1, It is characterized in that The at least three near-infrared lights of different wavelengths are specifically five near-infrared lights with wavelengths of 1300nm, 1818nm, 1940nm, 2150nm and 2320nm respectively.

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