A glue refractive index and absorption rate detection method and detection system

Abstract

The present application relates to a kind of glue refractive index and absorption detection method and detection system, belong to optical characteristic detection technical field, solve the quantitative detection of the refractive index and absorption of transparent glue in prior art, cannot accurately understand the optical property of the glue used, leading to unable to effectively complete scientific experiment and product manufacturing etc. The detection method includes: preparing organic glass sample piece;Measure the transmittance of the organic glass sample piece without smearing the glue to be measured in air, calculate the absorption of the organic glass sample piece itself;The organic glass sample piece is smeared with the glue to be measured;After the glue solidifies, measure the transmittance of the organic glass sample piece coated with the glue to be measured;Turn off the light source, collect the ambient background spectrum, calculate the refractive index of the glue to be measured and the absorption under the specific coating thickness of the glue to be measured.The present application realizes the quantitative detection of the refractive index and absorption of glue.

Description

Technical Field

[0001] This invention relates to the field of optical property testing technology, and in particular to a method and system for testing the refractive index and absorptivity of transparent adhesive. Background Technology

[0002] Transparent adhesives are widely used in scientific experiments and product manufacturing. The optical properties of adhesives have a significant impact on the results of scientific experiments and the optical transparency of products. Refractive index and absorptivity are two important optical parameters of transparent adhesives. Accurate quantitative measurement of these parameters helps to better understand the optical properties of the adhesives used and to better complete scientific experiments and product manufacturing.

[0003] However, existing technologies lack effective means for quantitatively detecting the refractive index and absorption rate of transparent adhesives. Summary of the Invention

[0004] In view of the above analysis, the present invention aims to provide a method and system for detecting the refractive index and absorptivity of adhesives, so as to solve at least one of the problems in the prior art, such as the lack of quantitative detection of the refractive index and absorptivity of transparent adhesives, the inability to accurately understand the optical properties of the adhesives used, and the inability to effectively complete scientific experiments and product manufacturing.

[0005] In a first aspect, the present invention provides a method for detecting the refractive index and absorbance of adhesive, comprising the following steps:

[0006] Step 1: Prepare acrylic sample;

[0007] Step 2: Measure the light transmittance of the acrylic sample without the adhesive to be tested in the air, and calculate the absorption rate of the acrylic sample itself;

[0008] Step 3: Apply the adhesive to be tested to the acrylic sample;

[0009] Step 4: After the adhesive has cured, measure the light transmittance of the acrylic sample with the adhesive applied.

[0010] Step 5: Turn off the light source, collect the ambient background spectrum, and calculate the refractive index of the adhesive to be tested and the absorption rate of the adhesive at a specific coating thickness.

[0011] Optionally, the number of acrylic glass samples is three.

[0012] Optionally, step 2 includes the following steps:

[0013] Step i: Collect the spectral results P of the air without the plexiglass sample. 空气 (λ);

[0014] Step ii: Place the three acrylic glass samples without the adhesive to be tested into the detection system, and collect the spectral results P of the corresponding acrylic glass samples without the adhesive to be tested. 有机极璃 (λ);

[0015] Step iii: Turn off the light source and collect the ambient background spectrum P 环境本底 (λ), the absorptivity S of the plexiglass sample itself is calculated according to the formula. 有机玻璃 .

[0016] Optionally, the formula for calculating the absorptivity of the plexiglass sample itself is:

[0017]

[0018] In the formula, T 有机玻璃 P represents the light transmittance of an acrylic glass sample in air. 有机玻璃 (λ) represents the spectrum of the acrylic sample without the adhesive to be tested, P 环境本底 (λ) represents the environmental background spectrum, P 空气 (λ) represents the spectral results in air when no plexiglass sample is placed;

[0019] as well as

[0020] T 有机玻璃 =1-2*r 空气-有机玻璃 -S 有机玻璃

[0021] In the formula, T 有机玻璃 r represents the light transmittance of the acrylic glass sample in air. 空气-有机玻璃 The reflectance at the interface between air and the plexiglass sample is represented by s. 有机玻璃 This indicates the absorption rate of the acrylic glass sample itself.

[0022] Optionally, step 3 includes the following steps:

[0023] Step a: Apply the mixture to obtain the first test group;

[0024] Step b: Apply the mixture to obtain the second test group.

[0025] Optionally, step a includes: taking a piece of plexiglass sample, applying the adhesive to be tested to two opposite surfaces of the plexiglass sample respectively, to obtain a first adhesive layer and a second adhesive layer.

[0026] Optionally, step b includes: taking two more acrylic glass samples, applying the adhesive to be tested between the two acrylic glass samples to obtain a third adhesive layer.

[0027] Optionally, the first adhesive layer, the second adhesive layer, and the third adhesive layer have the same thickness.

[0028] Optionally, step 4 includes the following steps:

[0029] Step 41: Measure the transmittance of the first test group in air;

[0030] Step 42: Measure the transmittance of the second test group in air.

[0031] Secondly, the present invention provides a glue refractive index and absorptivity detection system for performing the above-mentioned detection method, comprising: a light source, an optical fiber, a collimating lens, a collimating lens fixing assembly, a connecting rod, a connecting rod fixing structure, and a spectrometer; the light source and the spectrometer are respectively connected to the collimating lens fixing assembly, the collimating lens fixing assembly is connected to the connecting rod, and is fixed to the worktable by the connecting rod fixing structure.

[0032] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0033] (1) There is a lack of effective means to quantitatively detect the refractive index and absorptivity of transparent adhesives in the existing technology. The present invention sets up detection steps in accordance with existing optical theory and calculates the numerical results of the refractive index and absorptivity of the adhesive, which is conducive to accurately understanding the optical properties of the adhesive used, and thus better completing scientific experiments and product manufacturing.

[0034] (2) In accordance with the requirements of the detection method of the present invention, the present invention has developed a detection system with a specific composition structure, which can ensure the smooth implementation of the glue refractive index and absorption rate detection method, and ensure the stable operation of each component of the detection system during the measurement process, so as to ensure the accuracy and reliability of the detection results.

[0035] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages will be obvious from the description or learned by practicing the invention. Attached Figure Description

[0036] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0037] Figure 1 This is a schematic diagram of the structure of the first test group;

[0038] Figure 2 This is a schematic diagram of the structure of the second test group;

[0039] Figure 3 This is a schematic diagram illustrating the process of measuring the transmittance at the end of the first test group.

[0040] Figure 4 This is a schematic diagram illustrating the process of measuring the transmittance at the end of the second test group.

[0041] Figure 5 This is a schematic diagram of the detection system structure according to an embodiment of the present invention;

[0042] Figure 6 A schematic diagram for measuring the spectral data of a sample without acrylic glass.

[0043] Figure 7 A schematic diagram for measuring the spectral data of an acrylic sample without the adhesive to be tested.

[0044] Figure 8 A schematic diagram for measuring the spectral data of the first group to be tested;

[0045] Figure 9 This is a schematic diagram for measuring the spectral data of the second group to be tested;

[0046] Figure 10 This is a schematic diagram of the connecting rod fixing structure.

[0047] Figure label:

[0048] 1-Broadband light source; 2-Fiber optic cable; 3-Collimating lens; 4-Adapter; 5-Connecting rod; 6-Connecting rod fixing structure; 7-Spectrometer; 8-First fixing component; 9-Second fixing component; 10-Screw; 11-Groove; 12-Mounting hole; 13-First adhesive layer; 14-Second adhesive layer; 15-Third adhesive layer; 16-Air; 17-Acrylic sample. Detailed Implementation

[0049] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0050] Transparent adhesives are widely used in scientific experiments and product manufacturing. The optical properties of adhesives have a significant impact on the results of scientific experiments and the optical transparency of products. Refractive index and absorptivity are two important optical parameters of transparent adhesives. Accurate quantitative measurement of these parameters helps to better understand the optical properties of the adhesives used and to better complete scientific experiments and product manufacturing.

[0051] Quantitative detection of the refractive index and absorptivity of the adhesive is mainly achieved by measuring the light transmittance of an acrylic sample coated with a certain thickness of transparent adhesive. Experiments show that when a light beam is incident on the interface between two isotropic and transparent homogeneous media, it will propagate according to the laws of reflection and refraction. If the incident light is perpendicular to the interface, the reflectivity at the interface can be expressed as:

[0052]

[0053] Here, n1 and n2 correspond to the refractive indices of the two media, respectively. Besides reflection at the interface between the media, even when propagating in a homogeneous medium, the light beam interacts with the medium, specifically through light absorption. Therefore, the refractive index of the adhesive primarily affects light beam transmission at the interface, while the absorptivity affects light beam transmission more significantly within the adhesive itself. Both factors work together, making it necessary to understand and master the physical properties of the refractive index and absorptivity of transparent adhesives.

[0054] Firstly, this invention provides a method for quantitatively detecting the refractive index and absorbance of transparent adhesive. The following is in conjunction with... Figures 1-10 This invention provides a detailed description of its method for detecting the refractive index and absorbance of transparent adhesives, comprising the following steps:

[0055] Step 1: Prepare three acrylic glass samples with known refractive indices 17.

[0056] To measure the refractive index and absorptivity of the adhesive, it is necessary to apply the adhesive to the surface of an acrylic sample. The refractive index of the acrylic sample is known to be 1.493.

[0057] In one embodiment, the three acrylic glass samples are identical in size and manufacturing process.

[0058] Since the refractive indices of air 16 and plexiglass sample 17 are known, the reflectance r at the interface between air and plexiglass sample can be calculated using expression (1). 空气-有机玻璃 Macroscopically, when a light beam passes through an acrylic sample, two interface reflections occur, affecting the measured transmittance T of the acrylic sample in air. 有机玻璃 The reflectance results r at the interface between air and plexiglass sample 空气-有机玻璃 Substituting into expression (2), the absorptivity S of the plexiglass sample can be calculated. 有机玻璃 The process is as follows:

[0059] T 有机玻璃 =1-2*r 空气-有机玻璃 -S 有机玻璃 (2)

[0060] In the formula, T 有机玻璃 r represents the light transmittance of the acrylic glass sample in air. 空气-有机玻璃 S represents the reflectivity at the interface between air and the plexiglass sample. 有机玻璃 This indicates the absorption rate of the acrylic glass sample itself.

[0061] Step 2: Using a detection system, measure the transmittance of three acrylic glass samples (without the adhesive to be tested) in air at a wavelength λ, and calculate the absorptivity of the acrylic glass samples themselves. This includes the following steps:

[0062] Step i: As Figure 6 As shown, the spectral results P of the air without the plexiglass sample were collected. 空气 (λ). Specifically, by turning on the light source and connecting the spectrometer, the spectral display results can be seen in real time.

[0063] Step ii: As Figure 7 As shown, three acrylic glass samples without the adhesive to be tested were placed into the testing system, and the spectral results P of the corresponding acrylic glass samples without the adhesive to be tested were collected. 有机玻璃 (λ).

[0064] During measurement, one surface of the acrylic sample can be placed against the surface of the first fixing member of the collimating lens fixing assembly. The acrylic sample rests on the connecting rod between the first and second fixing members of the collimating lens fixing assembly, which ensures that the acrylic sample remains stationary during the measurement process. After the spectrometer data stabilizes, the corresponding spectrum is acquired.

[0065] Step iii: Turn off the light source and collect the ambient background spectrum P 环境本底 (λ).

[0066] The transmittance of the three acrylic glass samples in air before applying the adhesive was calculated according to formula (3).

[0067]

[0068] Substituting the above results into expression (2), the absorption rate S of each of the three plexiglass samples can be calculated. 有机玻璃 (corresponding to S1, S2, and S3), while the reflectivity r at the interface between the air and the plexiglass sample 空气-有机玻璃 (R3) can be calculated according to expression (1) (the refractive index of air is 1, and the refractive index of plexiglass is 1.493).

[0069] Step 3: Apply the adhesive to be tested onto the acrylic sample, including the following steps:

[0070] Step a: Apply the mixture to obtain the first test group. For example... Figure 1 As shown, a piece of acrylic glass is taken, and the adhesive to be tested is applied to two opposite surfaces of the acrylic glass sample. The application should be uniform and free of air bubbles, resulting in a first adhesive layer 13 and a second adhesive layer 14. The first adhesive layer 13 and the second adhesive layer 14 have the same thickness. The first adhesive layer, the second adhesive layer, and the acrylic glass sample constitute the first test group.

[0071] Step b: As Figure 2 As shown, two more acrylic glass samples were taken, and the adhesive to be tested was applied between the two samples. The application was required to be uniform and free of air bubbles, forming a "sandwich" structure, resulting in a third adhesive layer 15. The thickness of the third adhesive layer 15 was the same as the thickness of the first adhesive layer 13 and the second adhesive layer 14. The third adhesive layer and the two acrylic glass samples constituted the second test group.

[0072] Step 4: After the adhesive has cured, measure the light transmittance of the acrylic sample with the adhesive applied, including the following steps:

[0073] Step 41: Measure the transmittance of the first test group in air at wavelength λ.

[0074] First, collect the spectral results P when the sample is not included in the first test group. 空气 (λ).

[0075] Next, as Figure 8 As shown, the spectral results P after being placed into the first test group are collected. 第一组 (λ).

[0076] During the transmission of a light beam through an acrylic glass sample, the interface and interior of the medium affect the light beam transmittance. Specifically, the interface affects the transmittance through reflection, and the interior of the medium affects it through absorption.

[0077] For the first test group, such as Figure 3 As shown, the end transmittance measurement process is as follows: The incident light beam is first reflected at the interface between air and adhesive (reflectivity R1), causing a decrease in light transmittance. After entering the adhesive, the light transmittance decreases further due to absorption within the adhesive (absorption rate A for a specific adhesive coating thickness). Then, reflection occurs at the interface between the adhesive and the acrylic sample (reflectivity R2). After entering the acrylic sample, the light transmittance decreases further due to absorption within the acrylic sample (absorption rate S1 for the acrylic sample used in the first test group). Next, reflection occurs again at the interface between the acrylic sample and adhesive (reflectivity R2). After entering the adhesive, absorption occurs again within the adhesive (absorption rate A for a specific adhesive coating thickness), and reflection occurs again at the interface between the adhesive and air (reflectivity R1), finally yielding the light transmittance T1 at the end of the coating in the first test group.

[0078] The transmittance measurement result T1 of the first test group can be expressed as Equation (4):

[0079] R1+A+R2+S1+R2+A+R1=2R1+2R2+2A+S1=1-T1 (4)

[0080] In the formula, R1, A, R2 and S1 represent the reflectivity at the interface between the adhesive and air, the absorption rate of the transparent adhesive at a specific coating thickness, the reflectivity at the interface between the adhesive and the acrylic sample, and the absorption rate of the acrylic sample used in the first group, respectively.

[0081] Step 42: Measure the transmittance of the second test group in air at wavelength λ.

[0082] First, collect the spectral results P before the second test group was included. 空气 (λ).

[0083] Next, as Figure 9 As shown, the spectral results P after being placed into the second test group are collected. 第二组 (λ).

[0084] For the second test group, such as Figure 4 As shown, the end transmittance measurement process is as follows: the incident light beam is first reflected at the interface between the air and the first piece of plexiglass sample (reflectance is R). s This leads to a decrease in light transmittance. Upon entering the first acrylic sample, absorption occurs within the sample (the absorption rate of the first acrylic sample used in the second application is S2), further reducing light transmittance. Then, reflection occurs at the interface between the first acrylic sample and the adhesive (reflectance rate R2). Upon entering the adhesive, absorption occurs within the adhesive (absorption rate A at a specific application thickness), and reflection occurs at the interface between the adhesive and the second acrylic sample (reflectance rate R2). Upon entering the second acrylic sample, absorption occurs within it (absorption rate S3 in the second application), and reflection occurs at the interface between the second acrylic sample and air (reflectance rate R). s Finally, the transmittance T2 of the beam at the end of the second test group was obtained.

[0085] The transmittance measurement result T2 of the second test group can be expressed as Equation (5):

[0086] R3+s2+R2+A+R2+S3+R3=2R3+2R2+A+s2+S3=1-T2 (5)

[0087] In the formula, R3, S2 and S3 represent the reflectivity at the interface between the plexiglass sample and the air, and the absorptivity of the two plexiglass samples used in the second test group, respectively.

[0088] According to equation (1), R3 can be expressed as:

[0089]

[0090] In the formula, R3 represents the reflectivity at the interface between the acrylic glass sample and air, and n 空气 n represents the refractive index of air. 育机玻璃 This indicates the refractive index of the acrylic glass sample.

[0091] Substituting the refractive index data of air and the refractive index data of the plexiglass sample into the above formula, R3 is calculated.

[0092] Equation (6) can be obtained by multiplying expression (5) by 2 and then by equation (4):

[0093] 4R3+2R2-2R1+2S2+2S3-S1=2(1-T2)-(1-T1) (6)

[0094] Furthermore, we can obtain:

[0095] R2-R1=[2(1-T2)-(1-T1)-4R3-2s2-2S3+S1] / 2 (7)

[0096] Specifically, according to equation (1), R2 and R1 can be expressed as:

[0097]

[0098]

[0099] Step 5: Turn off the light source and collect the ambient background spectrum P 环境本底 (λ).

[0100] The transmittance results (T1 and T2) of the first and second test groups in air at wavelength λ were calculated according to expression (3), as follows:

[0101]

[0102] and

[0103]

[0104] At this point, R3, s2, S3, S1, T2, and T1 have all been obtained. Substituting expressions (8) and (9) into expression (7), the refractive index n of the glue is calculated. 胶水 Next, substitute expressions (8) and (9) into expression (5) to calculate the quantitative result A of the absorption rate of the transparent glue at a specific coating thickness.

[0105] Secondly, this invention provides a system for detecting the refractive index and absorption rate of transparent adhesive, used to perform the detection method of Example 1. For example... Figure 5As shown, the detection system includes a broadband light source 1, an optical fiber 2, a collimating lens 3, a collimating lens fixing assembly, an adapter 4, a connecting rod 5, a connecting rod fixing structure 6, a spectrometer 7, and a data acquisition device.

[0106] The light source and spectrometer are respectively connected to the collimating lens fixing assembly, which is connected to the connecting rod and fixed to the worktable by the connecting rod fixing structure.

[0107] Specifically, the collimating lens fixing assembly is used to fix the collimating lens 3, and includes a first fixing member 8 and a second fixing member 9. The first fixing member 8 and the second fixing member 9 have the same structure. The structure of the first fixing member 8 will be described in detail below.

[0108] like Figure 5 As shown, the longitudinal section of the first fixing member 8 is shaped like a cross, and it has a central hole. The lower part of the first fixing member 8 has a through hole for the connecting rod 5 to pass through. Specifically, the first fixing member 8 has two through holes, which are arranged symmetrically along an axis.

[0109] The connecting rod 5 is used to support the collimating lens fixing assembly. There are two connecting rods, and the two connecting rods pass through the two through holes on the first fixing member 8 respectively.

[0110] The adapter 4 is used to connect and fix the collimating lens 3 to the collimating lens fixing assembly. Specifically, the adapter 4 is a hollow cylinder with a fixing hole on its side wall. A screw is installed in the fixing hole. A part of the collimating lens 3 is inserted into the adapter 4 and fixedly connected to the adapter 4 by the screw in the fixing hole.

[0111] The outer wall of the adapter 4 is provided with external threads, and the center hole of the first fixing member 8 is provided with internal threads. The adapter 4 and the first fixing member 8 are fixedly connected by threads.

[0112] The broadband light source 1 emits light at wavelengths of 340–2000 nm, while the detection primarily utilizes the 400–780 nm visible light band. The broadband light source 1 is connected to a collimating lens 3 fixed to the first mounting component 8 via optical fiber 2. The collimating lens 3 outputs parallel light. The spectrometer 7 is connected to the collimating lens 3 fixed to the second mounting component 9 via optical fiber 2. A data acquisition device (not shown in the figure) is connected to the spectrometer 7 to acquire spectral data in real time. The spectral data includes both the operating wavelength and the corresponding count value.

[0113] Two connecting rods pass through the through holes on the two fixing members in sequence, and are fixedly connected to the fixing members and connecting rods 5 by screws 10 provided on the side of the fixing members. A gap is left between the two fixing members. The plexiglass sample coated with the adhesive to be tested is placed on the two connecting rods between the two fixing members and is in contact with at least one of the first fixing member 8 and the second fixing member 9 to ensure that the plexiglass sample remains stable during the measurement process.

[0114] In one embodiment, one surface of the plexiglass sample is abutted against the first fastener 8.

[0115] The connecting rod fixing structure 6 is used to fix the connecting rod 5 and achieve a fixed connection with the worktable to ensure the stability of the collimating lens fixing assembly. There are two connecting rod fixing structures 6, one at each end of the connecting rod 5. Specifically, as shown... Figure 10 As shown, the connecting rod fixing structure 6 has grooves 11 at both ends for the connecting rod 5 to pass through, and a fixing hole for the screw to pass through is provided on one side wall of the groove 11. After the connecting rod 5 is placed in the groove 11, the connecting rod fixing structure 6 and the connecting rod 5 are fixedly connected by tightening the screw.

[0116] In one embodiment, the connecting rod fixing structure 6 is further provided with mounting holes 12 for bolts to pass through, thereby achieving a fixed connection between the connecting rod fixing structure 6 and the worktable via bolts. Specifically, the mounting holes 12 are equidistant from the two grooves on the connecting rod fixing structure.

[0117] Example 1

[0118] Three acrylic glass samples with a refractive index of 1.493 were used. The refractive index and absorptivity of the transparent adhesive under test at a working wavelength of 420 nm were measured using a transmittance measurement system. The thickness of the transparent adhesive coating was considered to be 100 micrometers.

[0119] Using expression (1), the reflectivity R3 at the interface between air and plexiglass samples is calculated to be 3.91%. Before applying the adhesive, the transmittance of the three plexiglass samples at a working wavelength of 420nm in air was measured to be 89.58%, 87.83%, and 89.29%, respectively. Using expression (2), the absorptivity of the three plexiglass samples at a working wavelength of 420nm was calculated to be S1 = 2.60%, s2 = 4.35%, and s3 = 2.89%, respectively. After applying the adhesive, the transmittance of the two groups of adhesives was measured, with the thickness of the adhesives considered to be 100 micrometers. The measured transmittance of the first group at a working wavelength of 420nm was T1 = 81.19%, and the transmittance of the second group at a working wavelength of 420nm was T2 = 79.99%. Using expression (6), we can obtain:

[0120]

[0121] Therefore, the refractive index n of the transparent adhesive under test at a working wavelength of 420nm can be calculated. 胶水 ≈1.435; using expression (4), the absorption rate of transparent adhesive at a working wavelength of 420nm can be calculated to be A≈4.87% when the coating thickness is 100 micrometers.

[0122] The same operation can be performed to obtain the refractive index and absorbance of the transparent adhesive at other working wavelengths.

[0123] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A method for detecting the refractive index and absorbance of adhesive, characterized in that, Includes the following steps: Step 1: Prepare acrylic sample; Step 2: Measure the light transmittance of the acrylic sample without the adhesive to be tested in the air, and calculate the absorption rate of the acrylic sample itself; Step 3: Apply the adhesive to be tested to the acrylic sample; Step 4: After the adhesive has cured, measure the light transmittance of the acrylic sample with the adhesive applied. Step 5: Turn off the light source, collect the ambient background spectrum, and calculate the refractive index and absorbance of the adhesive to be tested; Step 3 includes the following steps: Step a: Apply the mixture to obtain the first test group; Step b: Apply the mixture to obtain the second test group; Step a includes: taking a piece of plexiglass sample, applying the adhesive to be tested to two opposite surfaces of the plexiglass sample respectively, to obtain a first adhesive layer and a second adhesive layer; Step b includes: taking two more acrylic glass samples, applying the adhesive to be tested between the two acrylic glass samples to obtain a third adhesive layer; The first adhesive layer, the second adhesive layer, and the third adhesive layer have the same thickness; Step 4 includes the following steps: Step 41: Measure the transmittance of the first test group in air; Step 42: Measure the transmittance of the second test group in air; The transmittance measurement results of the first test group at the end Represented as equation (4): （4） In the formula, , and These represent the reflectance at the interface between the adhesive and air, the absorption rate of the transparent adhesive at a specific coating thickness, the reflectance at the interface between the adhesive and the acrylic sample, and the absorption rate of the acrylic sample used in the first group, respectively. The transmittance measurement result T2 of the second test group is expressed as equation (5): （5） In the formula, and These represent the reflectance at the interface between the acrylic glass sample and the air, and the absorptivity of the two acrylic glass samples used in the second test group, respectively. Equation (5) × 2 - Equation (4) yields Equation (7): （7） and Represented as: （8） （9）。 2. The detection method according to claim 1, characterized in that, There are three acrylic glass samples.

3. The detection method according to claim 2, characterized in that, Step 2 includes the following steps: Step i: Collect spectral results of air without placing the plexiglass sample. ; Step ii: Place the three acrylic glass samples without the adhesive to be tested into the testing system respectively, and collect the spectral results of the corresponding acrylic glass samples without the adhesive to be tested. ; Step iii: Turn off the light source and collect the ambient background spectrum. The absorptivity of the acrylic glass sample was calculated using the formula. .

4. The detection method according to claim 3, characterized in that, The formula for calculating the absorptivity of the acrylic glass sample itself is: In the formula, This indicates the light transmittance of the acrylic glass sample in air. This represents the spectrum of an acrylic sample without the adhesive applied to it. Indicates the background spectrum of the environment. This represents the spectral results of air without the acrylic sample placed inside; as well as In the formula, This indicates the light transmittance of the acrylic glass sample in air. This indicates the reflectivity at the interface between the air and the plexiglass sample. This indicates the absorption rate of the acrylic glass sample itself.

5. A system for detecting the refractive index and absorption rate of adhesive, characterized in that, The instrument for performing the detection method according to any one of claims 1-4 includes: a light source, an optical fiber, a collimating lens, a collimating lens fixing assembly, a connecting rod, a connecting rod fixing structure, and a spectrometer. The light source and the spectrometer are respectively connected to the collimating lens fixing assembly, which is connected to the connecting rod and fixed to the worktable by the connecting rod fixing structure.

Images