Method and system for measuring spectral emissivity of semitransparent material

Abstract

The invention relates to the technical field of semitransparent material emissivity measuring methods, and discloses a semitransparent material spectral emissivity measuring method and system.The semitransparent material spectral emissivity measuring method comprises the steps that a measuring hole of an integrating sphere is plugged by a plug, a laser is turned off, and a detector outputs a first level value upsilon0; the laser is started, and the detector outputs a second level value v1; a sample to be detected is placed at the light inlet hole, the laser is started, and the detector outputs a third level value upsilon2; calculating the transmittance tau; removing the plug, placing the measured sample at the measuring hole, starting the laser, and outputting a fourth level value v3 by the detector; removing the measured sample, placing the standard diffuse reflection rate sheet at the measuring hole, starting the laser, and outputting a fifth level value upsilon4 by the detector; calculating the reflectivity rho; and calculating the emissivity epsilon. The measuring system comprises an integrating sphere, a laser sphere, a detector, a plug and a standard diffuse reflection rate sheet. The measurement precision is high, and the error is small.

Description

Technical Field

[0001] The present invention relates to the technical field of emissivity measurement methods for translucent materials, and in particular to a spectral emissivity measurement method and system for translucent materials. Background Art

[0002] The energy comparison method is one of the commonly used methods for emissivity measurement. In the prior art, when using the energy comparison method to measure the emissivity of a low-temperature object, there are two main error sources: the measurement error of temperature, and the temperature difference between the reference blackbody and the sample, and the isothermal condition cannot be fully guaranteed; when measuring the radiation of a translucent sample, the radiation of the heater behind the sample will pass through the sample and be superimposed on the radiation of the sample itself, and the radiation of the sample itself cannot be obtained.

[0003] Therefore, there is an urgent need for a spectral emissivity measurement method and system for translucent materials to solve the above problems. Summary of the Invention

[0004] Based on the above, the purpose of the present invention is to provide a spectral emissivity measurement method and system for translucent materials, with relatively high measurement accuracy and small error.

[0005] To achieve the above object, the present invention adopts the following technical solutions:

[0006] A spectral emissivity measurement method for a translucent material, comprising the following steps:

[0007] Seal the measurement hole of the integrating sphere with a plug, turn off the laser, and the detector outputs a first level value υ0;

[0008] Turn on the laser, the laser beam emitted by the laser enters the integrating sphere from the light inlet hole and hits the plug, and the detector outputs a second level value υ1;

[0009] Place the sample to be measured at the light inlet hole, turn on the laser, the laser beam emitted by the laser is aligned with the sample to be measured, and the detector outputs a third level value υ2;

[0010] Calculate the spectral transmittance τ of the sample to be measured for the incident energy from the first radiation value υ0, the second radiation value υ1, and the third radiation value υ2;

[0011] Remove the plug, place the sample to be measured at the measurement hole, turn on the laser, the laser beam emitted by the laser enters the integrating sphere from the light inlet hole and hits the sample to be measured, and the detector outputs a fourth level value υ3;

[0012] Remove the sample to be measured, place the standard diffuse reflectance sheet at the measurement hole, turn on the laser, the laser beam emitted by the laser enters the integrating sphere through the light incident hole and irradiates the standard diffuse reflectance sheet, and the detector outputs the fifth level value υ4;

[0013] Calculate the spectral reflectance ρ of the sample to be measured for the incident energy from the first radiation value υ0, the fourth radiation value υ3 and the fifth radiation value υ4;

[0014] According to Kirchhoff's law and the law of conservation of energy, calculate the spectral normal emissivity ε of the sample to be measured for the incident energy from the reflectance ρ and the transmittance τ.

[0015] As a preferred scheme of the spectral emissivity measurement method for a semi-transparent material, when calculating the spectral transmittance τ of the sample to be measured for the incident energy, the basis expression is as follows:

[0016]

[0017] As a preferred scheme of the spectral emissivity measurement method for a semi-transparent material, when calculating the spectral reflectance ρ of the sample to be measured for the incident energy, the basis expression is as follows:

[0018]

[0019] In the formula, ρ0 is the spectral reflectance of the standard diffuse reflectance sheet.

[0020] As a preferred scheme of the spectral emissivity measurement method for a semi-transparent material, according to Kirchhoff's law, the emissivity and absorptivity of the sample to be measured are equal under the thermal equilibrium state. When calculating the spectral normal emissivity ε of the sample to be measured for the incident energy from the reflectance ρ and the transmittance τ, the basis expression is as follows:

[0021] ε = α = 1 - ρ - τ,

[0022] In the formula, α is the spectral absorptivity of the sample to be measured for the incident energy.

[0023] A spectral emissivity measurement system for a semi-transparent material is used to implement the spectral emissivity measurement method for a semi-transparent material described in any of the above technical solutions. The spectral emissivity measurement system for a semi-transparent material includes:

[0024] An integrating sphere, on which a light incident hole, a measurement hole and a detection port are spaced apart, and the detection port is located between the measurement hole and the light incident hole;

[0025] A laser, the laser emission end of which is aligned with the light incident hole;

[0026] A detector, which is arranged at the detection port and is used to measure the light energy in the integrating sphere;

[0027] A plug, which can block the measurement hole;

[0028] A standard diffuse reflectance sheet, which can be placed at the measurement hole.

[0029] As a preferred solution of a spectral emissivity measurement system for a semi-transparent material, it further includes:

[0030] A calculation module, which is communicatively connected to the detector, and the calculation module can obtain the level value of the output signal of the detector.

[0031] As a preferred solution of a spectral emissivity measurement system for a semi-transparent material, one side of the plug is set as an arc surface. When the plug blocks the measurement hole, the arc surface and the inner wall of the integrating sphere form a continuous circular arc surface.

[0032] As a preferred solution of a spectral emissivity measurement system for a semi-transparent material, the plug is made of the same material as the integrating sphere.

[0033] The beneficial effects of the present invention are:

[0034] The present invention provides a method for measuring the spectral emissivity of a semi-transparent material. By detecting the light energy in the integrating sphere when the laser is not turned on and the plug blocks the measurement hole with a detector, the background noise of the detector is obtained, which is convenient for eliminating the influence of the background noise in the subsequent calculation process and improving the measurement accuracy; by measuring the transmittance and reflectance of the sample to be measured, the emissivity of the sample to be measured can be calculated according to Kirchhoff's law and the law of conservation of energy, avoiding the influence of the heater radiation when directly measuring the emissivity, with relatively high measurement accuracy and small error.

[0035] The present invention also provides a spectral emissivity measurement system for a semi-transparent material. Through this spectral emissivity measurement system for a semi-transparent material, the above-mentioned method for measuring the spectral emissivity of a semi-transparent material is realized to measure and obtain the emissivity of the sample to be measured, with relatively high measurement accuracy and small error. Description of the Drawings

[0036] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments of the present invention. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained according to the content of the embodiments of the present invention and these drawings.

[0037] Figure 1It is a schematic diagram of the structure of the spectral emissivity measurement system for translucent materials provided by an embodiment of the present invention Figure 1 ;

[0038] Figure 2 It is a schematic diagram of the structure of the spectral emissivity measurement system for translucent materials provided by an embodiment of the present invention Figure 2 ;

[0039] Figure 3 It is a schematic diagram of the structure of the spectral emissivity measurement system for translucent materials provided by an embodiment of the present invention Figure 3 ;

[0040] Figure 4 It is a schematic diagram of the structure of the spectral emissivity measurement system for translucent materials provided by an embodiment of the present invention Figure 4 ;

[0041] Figure 5 It is a schematic diagram of the structure of the spectral emissivity measurement system for translucent materials provided by an embodiment of the present invention Figure 5 。

[0042] In the figure:

[0043] 1. Integrating sphere; 2. Laser; 3. Detector; 4. Plug; 5. Standard diffuse reflectance sheet; 6. Test sample; 10. Measurement hole; 20. Light inlet hole; 30. Measurement hole. Specific embodiments

[0044] The present invention will be further described in detail below with reference to the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the present invention, rather than limiting the present invention. In addition, it should be noted that, for the sake of convenience of description, only the parts related to the present invention are shown in the drawings, rather than all the structures.

[0045] In the description of the present invention, unless otherwise clearly defined and limited, the terms "connected", "connected to", and "fixed" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or integrated; it can be a mechanical connection or an electrical connection; it can be directly connected or indirectly connected through an intermediate medium, and it can be the communication inside two elements or the interaction relationship between two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific situations.

[0046] In the present invention, unless otherwise clearly specified and defined, the first feature being "on" or "under" the second feature may include direct contact between the first and second features, or may include the situation where the first and second features are not in direct contact but in contact through additional features therebetween. Moreover, the first feature being "above", "over" and "on top of" the second feature includes that the first feature is directly above and obliquely above the second feature, or merely indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature being "under", "beneath" and "underneath" the second feature includes that the first feature is directly below and obliquely below the second feature, or merely indicates that the horizontal height of the first feature is lower than that of the second feature.

[0047] In the description of this embodiment, the orientation or positional relationships such as "upper", "lower", "left" and "right" are based on the orientation or positional relationships shown in the drawings, and are only for the convenience of description and simplifying the operation, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus cannot be construed as a limitation to the present invention. In the description of the present invention, unless otherwise stated, the meaning of "a plurality of" is two or more. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0048] As Figures 1 to 5 shown, this embodiment provides a method for measuring the spectral emissivity of a translucent material, and this method for measuring the spectral emissivity of a translucent material includes the following steps:

[0049] S100: Plug the measurement hole 10 of the integrating sphere 1 with the plug 4, turn off the laser 2, and the detector 3 outputs a first level value υ0;

[0050] In this embodiment, the plug 4 and the integrating sphere 1 are made of the same material. When the plug 4 plugs the measurement hole 10, the plug 4 and the inner wall of the integrating sphere 1 form a continuous spherical surface, so that the detector 3 can measure an accurate background level value of the detector 3, which is convenient for eliminating the influence of background noise in the subsequent calculation process and improving the measurement accuracy.

[0051] S200: Refer to Figure 2 , turn on the laser 2, the laser beam emitted by the laser 2 enters from the light inlet hole 20 of the integrating sphere 1 and irradiates to the plug 4, and the detector 3 outputs a second level value υ1; preferably, the laser beam enters from the light inlet hole 20 of the integrating sphere 1 and vertically irradiates to the center of the surface of the plug 4, and the incident energy forms a uniform distribution after multiple reflections in the integrating sphere 1.

[0052] S300: Refer to Figure 3 , place the sample to be measured 6 at the light inlet hole 20, turn on the laser 2, the laser beam emitted by the laser 2 is aligned with the sample to be measured 6, and the detector 3 outputs a third level value υ2.

[0053] Preferably, the sample 6 to be measured is disposed opposite to the plug 4, and the laser beam emitted by the laser 2 is perpendicularly incident on the center of the surface of the sample 6 to be measured. After passing through the sample 6 to be measured, part of the energy is reflected, and part of the energy passes through the sample 6 to be measured and enters the integrating sphere 1, where it undergoes multiple reflections to form a uniform distribution.

[0054] S400: Calculate the spectral transmittance τ of the sample 6 to be measured for the incident energy from the first radiation value υ0, the second radiation value υ1, and the third radiation value υ2;

[0055] Specifically, when calculating the spectral transmittance τ of the sample 6 to be measured for the incident energy, the basis is the following expression:

[0056]

[0057] Measure the energy that enters the integrating sphere 1 after passing through the sample 6 to be measured and the energy that directly enters the integrating sphere 1 without passing through the sample 6 to be measured through the detector 3. The ratio of the two energies can represent the transmittance of the sample 6 to be measured. Among them, the energy output detected by the detector 3 is a level value. At the same time, the background noise of the detector 3 is also measured during the measurement process. During the calculation process, the background noise is eliminated to obtain the actual energy, making the calculated transmittance more accurate.

[0058] S500: Refer to Figure 4 , remove the plug 4, place the sample 6 to be measured at the measurement hole 10, turn on the laser 2, and the laser beam emitted by the laser 2 enters the integrating sphere 1 from the light incident hole 20 and irradiates the sample 6 to be measured. The detector 3 outputs a fourth level value υ3.

[0059] The laser beam enters the integrating sphere 1 and is perpendicularly incident on the center of the surface of the sample 6 to be measured. After being reflected by the sample 6 to be measured and undergoing multiple reflections in the integrating sphere 1 to form a uniform distribution, the detector 3 measures the energy in the integrating sphere 1 after being reflected by the sample 6 to be measured and outputs it as a level value.

[0060] S600: Refer to Figure 5 , remove the sample 6 to be measured, place the standard diffuse reflectance sheet 5 at the measurement hole 10, turn on the laser 2, and the laser beam emitted by the laser 2 enters the integrating sphere 1 from the light incident hole 20 and irradiates the standard diffuse reflectance sheet 5. The detector 3 outputs a fifth level value υ4.

[0061] The laser beam enters the integrating sphere 1 and is perpendicularly incident on the center of the surface of the standard diffuse reflectance sheet 5. After being reflected by the standard diffuse reflectance sheet 5 and undergoing multiple reflections in the integrating sphere 1 to form a uniform distribution, the detector 3 measures the energy in the integrating sphere 1 after being reflected by the standard diffuse reflectance sheet 5 and outputs it as a level value.

[0062] S700: Calculate the spectral reflectance ρ of the sample 6 to the incident energy from the first radiation value υ0, the fourth radiation value υ3, and the fifth radiation value υ4;

[0063] Specifically, when calculating the spectral reflectance ρ of the sample 6 to the incident energy, the basis expression is as follows:

[0064]

[0065] In the formula, ρ0 is the spectral reflectance of the standard diffuse reflectance sheet 5, which is a known physical quantity with traceability.

[0066] By correcting through the reflectance curve of the standard diffuse reflectance sheet 5, the true reflectance of the sample 6 to be measured can be calculated. At the same time, the background noise of the detector 3 is also measured during the measurement process. During the calculation process, the background noise is eliminated to obtain the actual energy, so that the calculated reflectance is more accurate.

[0067] S800: According to Kirchhoff's law and the law of conservation of energy, calculate the spectral normal emissivity ε of the sample 6 to the incident energy from the reflectance ρ and the transmittance τ.

[0068] When calculating the spectral normal emissivity ε of the sample 6 to the incident energy from the reflectance ρ and the transmittance τ, the basis expression is as follows:

[0069] ε = α = 1 - ρ - τ,

[0070] In the formula, α is the spectral absorptance of the sample 6 to be measured to the incident energy.

[0071] Under the thermal equilibrium state, the emissivity and absorptance of the sample 6 to be measured are equal, and the sum of the absorptance, reflectance, and transmittance is 1. The transmittance and reflectance are calculated in the above process, and thus the spectral emissivity of the sample 6 to the incident energy can be calculated, avoiding the influence of the heater radiation when directly measuring the emissivity, with relatively high measurement accuracy and small error.

[0072] This embodiment also provides a spectral emissivity measurement system for a translucent material. This spectral emissivity measurement system for a translucent material is used to implement the above-mentioned spectral emissivity measurement method for a translucent material. Specifically, the spectral emissivity measurement system for a translucent material includes an integrating sphere 1, a laser 2, a detector 3, a plug 4, and a standard diffuse reflectance sheet 5. The integrating sphere 1 is provided with a light incident hole 20, a measurement hole 10, and a detection port 30 at intervals. The detection port 30 is located between the measurement hole 10 and the light incident hole 20. The laser emission end of the laser 2 is aligned with the light incident hole 20. The detector 3 is arranged at the detection port 30 and is used to measure the light energy in the integrating sphere 1. The plug 4 can block the measurement hole 10, and the standard diffuse reflectance sheet 5 can be placed at the measurement hole 10. When measuring the transmittance of the sample to be measured, first block the measurement hole 10 with the plug 4 for measurement, and then place the sample to be measured 6 at the light incident hole 20 for measurement; when measuring the reflectance of the sample to be measured, first place the sample to be measured 6 at the measurement hole 10 for measurement, and then place the standard diffuse reflectance sheet 5 at the measurement hole 10 for measurement; when measuring the background noise, block the measurement hole 10 with the plug 4 and turn off the laser 2 for measurement. Through this spectral emissivity measurement system for a translucent material, the above-mentioned spectral emissivity measurement method for a translucent material is implemented to measure and obtain the emissivity of the sample to be measured 6, with relatively high measurement accuracy and small error.

[0073] Preferably, one side of the plug 4 is set as an arc surface. When the plug 4 blocks the measurement hole 10, the arc surface forms a continuous circular arc surface with the inner wall of the integrating sphere 1. More preferably, the plug 4 and the integrating sphere 1 are made of the same material. This enables the detector 3 to accurately measure the background level value of the detector 3, thereby facilitating the elimination of the influence of background noise, improving the accuracy of the measurement and calculation of the emissivity, and reducing the measurement error.

[0074] In this embodiment, the spectral emissivity measurement system for a translucent material further includes a calculation module. The calculation module is communicatively connected to the detector 3. The calculation module can obtain the level value of the output signal of the detector 3, calculate the transmittance and reflectance of the sample to be measured 6 through the obtained level value, and calculate the emissivity of the sample to be measured 6 based on the transmittance and reflectance.

[0075] Note that the above is only the preferred embodiment of the present invention and the applied technical principle. Those skilled in the art will understand that the present invention is not limited to the specific embodiments described here. Various obvious changes, re-adjustments, and substitutions can be made by those skilled in the art without departing from the protection scope of the present invention. Therefore, although the present invention has been described in more detail through the above embodiments, the present invention is not limited to the above embodiments. Without departing from the inventive concept of the present invention, more other equivalent embodiments can be included, and the scope of the present invention is determined by the scope of the appended claims.

Claims

1. A method for measuring the spectral emissivity of a translucent material, characterized in that, It includes the following steps: Seal the measurement hole of the integrating sphere with a plug, turn off the laser, and the detector outputs the first level value υ0; Turn on the laser, the laser beam emitted by the laser enters from the light inlet hole of the integrating sphere and hits the plug, and the detector outputs the second level value υ1; Place the sample to be measured at the light inlet hole, turn on the laser, the laser beam emitted by the laser is aligned with the sample to be measured, and the detector outputs to the third level value υ2; Calculate the spectral transmittance τ of the sample to be measured for the incident energy from the first radiation value υ0, the second radiation value υ1, and the third radiation value υ2; Remove the plug, place the sample to be measured at the measurement hole, turn on the laser, the laser beam emitted by the laser enters the integrating sphere from the light inlet hole and hits the sample to be measured, and the detector outputs the fourth level value υ3; Remove the sample to be measured, place the standard diffuse reflectance sheet at the measurement hole, turn on the laser, the laser beam emitted by the laser enters the integrating sphere from the light inlet hole and hits the standard diffuse reflectance sheet, and the detector outputs the fifth level value υ4; Calculate the spectral reflectance ρ of the sample to be measured for the incident energy from the first radiation value υ0, the fourth radiation value υ3, and the fifth radiation value υ4; According to Kirchhoff's law and the law of conservation of energy, calculate the spectral normal emissivity ε of the sample to be measured for the incident energy from the reflectance ρ and the transmittance τ; 2. The method for measuring the spectral emissivity of a translucent material according to claim 1, characterized in that When calculating the spectral transmittance τ of the sample to be measured for the incident energy, the basis expression is as follows:

3. The method for measuring the spectral emissivity of a translucent material according to claim 1, characterized in that, When calculating the spectral reflectance ρ of the sample to be measured for the incident energy, the basis expression is as follows: In the formula, ρ0 is the spectral reflectance of the standard diffuse reflectance sheet.

4. The method for measuring the spectral emissivity of a translucent material according to claim 1, wherein According to Kirchhoff's law, the emissivity and absorptivity of the sample to be measured are equal under the thermal equilibrium state. When calculating the spectral normal emissivity ε of the sample to be measured for the incident energy from the reflectance ρ and the transmittance τ, the basis expression is as follows: ε = α = 1 - ρ - τ, In the formula, α is the spectral absorptivity of the sample to be measured for the incident energy.

5. A spectral emissivity measurement system for a translucent material, which is used to implement the spectral emissivity measurement method for the translucent material according to any one of claims 1-4, characterized in that, The spectral emissivity measurement system for the semi-transparent material includes: An integrating sphere, on which a light inlet hole, a measurement hole, and a detection port are spaced apart, and the detection port is located between the measurement hole and the light inlet hole; A laser, the laser emission end of which is aligned with the light inlet hole; A detector, which is arranged at the detection port and is used to measure the light energy in the integrating sphere; A plug, which can be sealed at the measurement hole; A standard diffuse reflectance sheet, which can be placed at the measurement hole.

6. The spectral emissivity measurement system for the translucent material according to claim 5, characterized in that It further includes: A calculation module, which is communicatively connected to the detector, and the calculation module can obtain the level value of the signal output by the detector.

7. The spectral emissivity measurement system for the translucent material according to claim 5, wherein One side of the plug is set as an arc surface. When the plug is sealed at the measurement hole, the arc surface forms a continuous circular arc surface with the inner wall of the integrating sphere.

8. The spectral emissivity measurement system for the translucent material according to claim 5, characterized in that, The plug is made of the same material as the integrating sphere.

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