A device and method for measuring the directional emissivity of a material at room temperature with adjustable incident angle

Abstract

The present invention provides a device and method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle, comprising a light source, an optical path system arranged in the incident direction of the light source; and a spectrum detector arranged in the optical path emission direction of the optical path system. The present invention adopts the above-mentioned device and method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle, which can quickly and accurately measure the reflection intensity of the material surface in various directions at room temperature under the conditions of incident light in different directions, and then calculate the emissivity in various directions according to Kirchhoff's law, with a short measurement time, and can be applied to various smooth and rough material surfaces.

Description

Technical Field

[0001] The invention relates to the field of material thermal property measurement, and in particular to a device and method for measuring material normal-temperature directional emissivity with adjustable incident angle. Background Art

[0002] Directional emissivity refers to the ratio of an object's emissivity in a specific direction to the radiation capacity of a black body at the same temperature in that direction. Under normal temperature conditions, the object temperature is low and the radiation energy is low. Directly measuring the emissivity background radiation has a great impact on the measurement uncertainty. Therefore, the measurement of room-temperature emissivity is usually performed by measuring the reflectivity and then inferring the emissivity of the sample based on Kirchhoff's law. However, due to the lack of devices for measuring the directional emissivity and directional reflectivity of smooth materials, the measurement application of directional emissivity at this principle level is missing. For the reflection method to measure the room-temperature directional emissivity of materials under various incident light directions, it is necessary to rotate the incident angle of the light source and the reflection angle of the detector to obtain the reflection signal under different incident light sources. Simplifying the rotation system of the device and eliminating the influence of background radiation on the measurement results is the key to improving measurement accuracy.

[0003] Patent CN117169273B discloses a device and method for measuring the directional emissivity of a material at room temperature based on the reflection method, including a light source, a parabolic mirror arranged in the direction of light transmission, a sample placement device arranged at the focus of the parabolic mirror, and a plane reflector group and a fixed plane mirror arranged movably along the direction of light transmission, and a spectrum receiver arranged at the end of the fixed plane mirror. During measurement, the sample is placed at the focus of the parabolic mirror, then the light source is turned off, the spectrum receiver is turned on, and the background radiation signal S1 when there is no light source is recorded; then the light source is turned on, and the total signal S2 of the sample reflection and background radiation in this direction is recorded; finally, the reflector group is moved to other positions, the measurement is repeated, and the emissivity is calculated. This patent is used to measure the directional emissivity of a rough surface under the normal incidence direction.

[0004] Patent CN110530525B discloses a directional emissivity measurement device based on the reflection method, including a heater and a light source, a plane reflector is provided on one side of the light source, and the angle between the mirror surface of the plane reflector and the main optical axis of the light source is 45°; a beam splitter cube is provided on one side of the plane reflector along the light transmission direction; a semi-parabolic reflector is provided on one side of the beam splitter cube, an off-axis parabolic reflector is provided on one side of the semi-parabolic reflector, and a photodetector is provided at the focus of the off-axis parabolic reflector; the sample surface in the heater coincides with the axial section of the semi-parabolic reflector. This patent measures the cumulative values ​​of emissivity in different azimuth directions under different incident light direction conditions, and cannot measure the individual data of emissivity in a single direction. Summary of the invention

[0005] The purpose of the present invention is to provide a device and method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle, which can realize the reflectivity measurement of the target surface under different incident directions and then calculate the reflectivity of the surface in various directions, and can provide the emission characteristics of the target surface in various directions at room temperature.

[0006] To achieve the above object, the present invention provides a device for measuring the directional emissivity of a material at room temperature with an adjustable incident angle, comprising a light source,

[0007] The optical path system is arranged in the incident direction of the light source;

[0008] The spectrum detector is arranged in the light path emission direction of the light path system;

[0009] The optical path system comprises a fixed plane reflector fixedly arranged in the light transmission direction, a hemispherical parabolic mirror, and a second plane reflector movably arranged.

[0010] Preferably, the optical path system further comprises an off-axis ellipsoidal mirror fixedly arranged in the light transmission direction, a sample placement device fixedly arranged at the focus of the hemispherical parabolic mirror, a hemispherical parabolic mirror fixedly arranged in the light transmission direction, and an off-axis parabolic mirror;

[0011] A plane reflector group and a fixed plane reflector are movably arranged in the light transmission direction.

[0012] Preferably, the off-axis ellipsoidal mirror comprises two focal points: a first focal point and a second focal point;

[0013] The first focus of the off-axis ellipsoidal mirror coincides with the focus of the off-axis parabolic mirror, and the second focus of the off-axis ellipsoidal mirror coincides with the focus of the hemispherical parabolic mirror;

[0014] A first opening is arranged below the off-axis parabolic mirror, and the first focus is located in the first opening.

[0015] Preferably, the plane reflector group is provided with a first plane reflector and a second plane radiating mirror, the first plane reflector is arranged in front of the incident light source, the second plane reflector is arranged at the end of the fixed plane mirror, and the second plane reflector is located above the third opening.

[0016] Preferably, a first push rod is provided on one side of the first plane reflector, and a first slide rail is provided on the other side of the first plane reflector.

[0017] Preferably, a second push rod is provided on the second plane reflector, and the second plane reflector is connected to a second slide rail provided on one side thereof.

[0018] Preferably, a belt is provided on one side of the second push rod, a rotating rod is provided on the other end of the belt, a fixed pulley is provided between the rotating rod and the second push rod, and the fixed pulley is connected to the belt; a sample is provided on one end of the rotating rod.

[0019] Preferably, the hemispherical parabolic mirror is provided with a bottom cover, the bottom cover is provided with a second opening, and the second focus, the sample placement device and the sample are located in the second opening;

[0020] The bottom cover is also provided with a third opening;

[0021] A fourth opening is arranged on the bottom cover below the fixed plane reflector.

[0022] A method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle comprises the following steps:

[0023] S1. Place the standard reflective gold plate at the second focus of the off-axis ellipsoidal mirror (the focus of the hemispherical parabolic mirror), and fix the plane reflector assembly at a specific position;

[0024] S2. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. G0 ;

[0025] S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ);

[0026] S4, move the plane reflector assembly to another position and repeat step S3;

[0027] S5, take out the standard reflective gold plate, place the sample to be tested at the first focus of the off-axis ellipsoidal mirror, and fix the plane reflector assembly at a specific position;

[0028] S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ;

[0029] S7. Turn on the light source, keep the position of the sample to be tested and the plane reflector group unchanged, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ);

[0030] S8, move the plane reflector assembly to another position and repeat step S7;

[0031] S9. Calculate the directional emissivity of the material surface at each angle ε(λ, θ, T) = 1-ρ S (λ, θ, T) = 1 - ρ G (λ,θ,T)(SS (θ)-S S0 ) / (S G (θ)-S G0 );

[0032] A method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle can be replaced by the following steps:

[0033] (1) When the measured material has a smooth surface:

[0034] S1. Place the standard reflective gold plate at the focus of the hemispherical parabolic mirror and fix the plane reflector group at a specific position;

[0035] S2. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. G0 ;

[0036] S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ);

[0037] S4, rotating the sample placement rod to another angle, and driving the plane reflector assembly to move to the corresponding position through the belt, and repeating steps S2-S3;

[0038] S5. Take out the standard reflection specimen, place the sample to be tested at the focus of the hemispherical parabolic mirror, and fix the plane reflector assembly at a specific position;

[0039] S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ;

[0040] S7. Turn on the light source, keep the position of the sample to be tested and the plane reflector group unchanged, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ);

[0041] S8, rotating the sample placement rod to another angle, and driving the plane reflector assembly to move to the corresponding position through the belt, and repeating steps S6-S7;

[0042] S9. Calculate the directional emissivity of the material surface at each angle ε(λ, θ, T) = 1-ρ S (λ, θ, T) = 1 - ρ G (λ,θ,T)(S S (θ)-S S0 ) / (S G (θ)-S G0 ).

[0043] (2) When the measured material has a rough surface:

[0044] S1. Place the standard reflective gold plate at the focus of the hemispherical parabolic mirror and fix the plane reflector group at a specific position;

[0045] S2. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. G0 ;

[0046] S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ);

[0047] S4, remove the belt, rotate the sample placement rod to another angle, move the plane reflector to a different position, and repeat steps S2-S3;

[0048] S5. Take out the standard reflection specimen, place the sample to be tested at the focus of the hemispherical parabolic mirror, and fix the plane reflector assembly at a specific position;

[0049] S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ;

[0050] S7. Turn on the light source, keep the position of the sample to be tested and the plane reflector group unchanged, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ);

[0051] S8, remove the belt, rotate the sample placement rod to another angle, move the plane reflector to a different position, and repeat steps S6-S7;

[0052] S9. Calculate the directional emissivity of the material surface at each angle ε(λ, θ, T) = 1-ρ S (λ, θ, T) = 1 - ρ G (λ,θ,T)(S S (θ)-S S0 ) / (S G (θ)-S G0 ).

[0053] Where ε(λ, θ, T) is the sample emissivity ρ S (λ, θ, T) is the sample reflectance, ρ G is the reflectivity of the standard reflective gold plate, λ is the wavelength, θ is the angle between the incident light and the sample normal, T is the sample surface temperature, S S0 To place the sample, when the light source is turned off, the detector receives the radiation signal of the light source, S S (θ) is the radiation signal of the light source received by the detector when the sample is placed and the light source is turned on, S G0When the light source is turned off, the standard reflection gold plate detector receives the radiation signal of the light source. G (θ) is the radiation signal of the light source received by the detector placed on a standard reflective gold plate when the light source is turned on.

[0054] Therefore, the present invention adopts the above-mentioned material room temperature directional emissivity measurement device and method with adjustable incident angle, and the technical effects are as follows:

[0055] According to the optical properties of the ellipsoidal mirror and the hemispherical parabolic mirror (i.e., the light emitted from the first focus of the ellipsoidal surface is reflected by the ellipsoidal mirror and converges at the second focus of the ellipsoidal surface, the incident light parallel to the parabola axis section is reflected by the hemispherical parabolic mirror and then emitted through the focus of the hemispherical parabolic mirror, and the light emitted from the focus of the parabola is reflected by the hemispherical parabolic mirror and then emitted parallel to the parabola axis section), a measuring device is designed to indirectly measure the directional emissivity of the smooth surface of the material under normal temperature conditions; the incident light in the same direction is converted into different directions by the off-axis parabolic mirror, and the reflected light is converted from different directions to the same direction by the hemispherical parabolic mirror, which saves the rotating device of the measuring system, eliminates the influence of background radiation changes on the measurement results, and improves the measurement speed and accuracy; theoretically, the measurement of directional emissivity of 0°-90° can be achieved (the measurement angle range can be adjusted according to the eccentricity of the ellipsoidal mirror). BRIEF DESCRIPTION OF THE DRAWINGS

[0056] Figure 1 A schematic diagram of a device for measuring the directional emissivity of a material at room temperature with an adjustable incident angle and a light beam according to Embodiment 1 of the present invention;

[0057] Figure 2 This is a schematic diagram of a device for measuring the directional emissivity of a material at room temperature with adjustable incident angle according to Embodiment 1 of the present invention;

[0058] Figure 3 It is a partial schematic diagram of a device for measuring the directional emissivity of a material at room temperature with adjustable incident angle according to the first embodiment of the present invention;

[0059] Figure 4 is a schematic diagram of a sample placement device according to Embodiment 1 of the present invention;

[0060] Figure 5 This is a partial schematic diagram of a device for measuring the directional emissivity of a material at room temperature with an adjustable incident angle in Example 2.

[0061] Reference numerals

[0062] 1. Light source; 2. Fixed plane reflector; 3. First plane reflector; 4. Off-axis parabolic mirror; 5. Off-axis ellipsoidal mirror; 6. Sample placement device; 7. Hemispherical parabolic mirror; 8. Second plane reflector; 9. Spectral detector; 10. Bottom cover; 11. First opening; 12. Second opening;

[0063] 13. Hemispherical parabolic mirror placement shell; 14. Outer shell; 15. Moving shell; 16. Off-axis ellipsoidal spherical mirror placement shell; 17. First connecting column; 18. Sliding assembly; 181. First slide rail; 182. First push rod; 183. Second slide rail; 184. Second push rod; 19. Optical path; 20. Third opening; 21. Fourth opening; 22. Rotating rod; 23. Belt; 24. Fixed pulley. DETAILED DESCRIPTION

[0064] The technical solution of the present invention is further described below through the accompanying drawings and embodiments.

[0065] Unless otherwise defined, technical or scientific terms used in the present invention shall have the common meanings understood by one having ordinary skills in the field to which the present invention belongs.

[0066] Embodiment 1

[0067] like Figure 1 , Figure 2 and Figure 3 As shown, a device for measuring the directional emissivity of a material at room temperature with an adjustable incident angle comprises a light source 1, an optical path system and a spectral detector 9, wherein a fixed plane reflector 2, a first plane reflector 3, an off-axis parabolic mirror 4, an off-axis ellipsoidal mirror 5, a sample placement device 6, a hemispherical parabolic mirror 7 and a second plane reflector 8 are sequentially arranged on the optical path system according to the light transmission direction.

[0068] Among them, the off-axis ellipsoidal mirror 5, the sample placement device 6, the hemispherical parabolic mirror 7 and the off-axis parabolic mirror 4 are fixedly arranged, and the off-axis ellipsoidal mirror 5 includes two foci: a first focus and a second focus. The first focus on the off-axis ellipsoidal mirror 5 coincides with the focus of the off-axis parabolic mirror 4, and the second focus on the off-axis ellipsoidal mirror 5 coincides with the focus of the hemispherical parabolic mirror 7.

[0069] Therefore, the positions of the first focus and the second focus do not change.

[0070] A bottom cover 10 is disposed on the hemispherical parabolic mirror 7 . A first opening 11 and a second opening 12 are disposed on the bottom cover 10 . The first focus is located in the first opening 11 , and the second focus and the sample placement device 6 are located in the second opening 12 .

[0071] The bottom cover 10 is also provided with a third opening 20 , through which the light reflected by the hemispherical parabolic mirror 7 passes to the second plane reflector 8 . Since the position of the second plane reflector 8 may be adjusted, the third opening 20 is a long opening.

[0072] Since the plane reflector group and the fixed plane reflector 2 are movably arranged, the plane reflector group includes the first plane reflector 3 and the second plane reflector 8 .

[0073] The angles between the first plane reflector 3, the second plane reflector 8, the fixed plane reflector 2 and the main axis of the light are all 45°, so the present invention can measure the emissivity of the sample at different angles. Specifically:

[0074] By adjusting the first plane reflector 3, the angle of the light source incident on the sample surface can be changed (0 to 90°), and by adjusting the second plane reflector 8, the corresponding reflected light can be received. By adjusting the direction of the incident light, the direction of the reflected light will change accordingly. The directions of the incident and reflected light are respectively changed from rotational change to planar movement through the off-axis parabolic mirror 4 and the hemispherical parabolic mirror 7, thereby simplifying the rotating device.

[0075] A hemispherical parabola mirror placement shell 13 is arranged outside the hemispherical parabola mirror 7 for fixing the hemispherical parabola mirror 7, an outer shell 14 is arranged above the hemispherical parabola mirror placement shell 13, the outer shell 14 is connected to the bottom cover 10, a movable shell 15 is arranged above the outer shell 14, and the outer shell 14 and the movable shell 15 are movably connected, or not connected, but just in contact. Among them, the outer shell 14 may not be arranged, so that the bottom cover 10 directly contacts the hemispherical parabola mirror placement shell 13 and the hemispherical parabola mirror 7.

[0076] An off-axis ellipsoidal mirror placement shell 16 is provided on the off-axis ellipsoidal mirror 5, and a first connecting column 17 is provided between the off-axis ellipsoidal mirror placement shell 16 and the bottom cover 10. The number of the first connecting column 17 is at least one. The first connecting column 17 and the off-axis ellipsoidal mirror placement shell 16 fix the off-axis ellipsoidal mirror 5 on the bottom cover 10.

[0077] A sliding assembly 18 is provided on the plane reflector group and the fixed plane reflector 2, and a first slide rail 181 is provided on the sliding assembly 18. The fixed plane reflector 2 is fixed at one end of the first slide rail 181, and a first plane reflector 3 is provided on the first slide rail 181 on one side of the fixed plane reflector 2. A first push rod 182 is also provided on the first plane reflector 3. The first push rod 182 penetrates the movable shell 15, and a part of the surplus is provided on the outside. The position of the first plane reflector 3 can be directly adjusted by the first push rod 182 on the outside. The first push rod 182 and the first plane reflector 3 can be movably connected or fixedly connected. When the first push rod 182 is movably connected, the first plane reflector 3 is moved while adjusting the angle between the first push rod 182 and the first plane reflector 3. When the first push rod 182 is fixedly connected, a corresponding long hole is provided on the movable shell 15, and the position of the first plane reflector 3 is adjusted when the first push rod 182 moves along the long hole.

[0078] The sliding assembly 18 is also provided with a second slide rail 183, which is connected to the second plane reflector 8. The second plane reflector 8 can slide on the second slide rail 183. The second plane reflector 8 is provided with a second push rod 184, which penetrates the movable shell 15, and a part of the margin is arranged on the outside, and the position of the second plane reflector 8 can be directly adjusted on the outside through the second push rod 184. The second push rod 184 and the second plane reflector 8 can be movably connected or fixedly connected. When the second push rod 184 is movably connected, the second plane reflector 8 is moved while adjusting the angle between the second push rod 184 and the second plane reflector 8. When the second push rod 184 is fixedly connected, a corresponding long hole is provided on the movable shell 15, and the second push rod 184 moves along the long hole to adjust the position of the second plane reflector 8.

[0079] The sliding assembly 18 may be directly fixed on the moving shell 15 or may be fixed to the moving shell 15 by setting a second connecting column, and the first slide rail 181 and the second slide rail 183 may be connected or not connected.

[0080] The spectrum detector 9 and the off-axis parabolic mirror 4 can be directly fixed on the moving shell 15 or can be fixed to the moving shell 15 by setting a third connecting column.

[0081] The light source 1 may be provided with a separate fixing device on the outside of the moving shell 15 for fixing the light source 1, or it may be directly fixed on the moving shell 15. In this case, a corresponding light channel is provided on the moving shell 15 to transmit light.

[0082] like Figure 4As shown, a mounting plate is provided on the sample placement device 6, a through hole is provided on the mounting plate, a boss is provided at the edge of the through hole and the mounting plate, and the sample is placed in the boss. Similarly, the sample placement device may not be provided with a mounting plate, and a boss is directly provided on the bottom cover at the second opening 12 to place the sample.

[0083] The wavelength ranges of the light source and the spectrum receiver correspond to each other.

[0084] The included angles between the first plane reflector, the second plane reflector, the fixed plane reflector and the main axis of the light are all 45 degrees.

[0085] A method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle comprises the following steps:

[0086] S1. Place the standard reflective gold plate at the second focus of the off-axis ellipsoidal mirror (the focus of the hemispherical parabolic mirror), and fix the plane reflector assembly at a specific position;

[0087] S2. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. G0 ;

[0088] S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ);

[0089] S4, move the plane reflector assembly to another position and repeat step S3;

[0090] S5, take out the standard reflective gold plate, place the sample to be tested at the first focus of the off-axis ellipsoidal mirror, and fix the plane reflector assembly at a specific position;

[0091] S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ;

[0092] S7. Turn on the light source, keep the standard sample to be tested and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ);

[0093] S8, move the plane reflector assembly to another position, and repeat steps S6-S7;

[0094] S9. Calculate the directional emissivity of the material surface at each angle ε(λ, θ, T) = 1-ρ S (λ, θ, T) = 1 - ρ G (λ,θ,T)(S S (θ)-S S0 ) / (S G(θ)-S G0 );

[0095] Where ε(λ, θ, T) is the sample emissivity; ρ S (λ, θ, T) is the sample reflectance, ρ G is the reflectivity of the standard reflective gold plate, λ is the wavelength, θ is the angle between the incident light and the sample normal, T is the sample surface temperature, S S0 To place the sample, when the light source is turned off, the detector receives the radiation signal of the light source, S S (θ) is the radiation signal of the light source received by the detector when the sample is placed and the light source is turned on, S G0 When the light source is turned off, the standard reflection gold plate detector receives the radiation signal of the light source. G (θ) is the radiation signal of the light source received by the detector placed on a standard reflective gold plate when the light source is turned on.

[0096] Embodiment 2

[0097] like Figure 5 As shown, a device for measuring the directional emissivity of a material at room temperature with an adjustable incident angle comprises a light source 1, an optical path system and a spectral detector 9, wherein a fixed plane reflector 2, a hemispherical parabolic mirror 7, a sample and a second plane reflector 8 are sequentially arranged on the optical path system according to the light transmission direction.

[0098] Among them, the fixed plane reflector 2 and the hemispherical parabolic mirror 7 are fixedly arranged, and the second plane reflector 8 is movably arranged. A second slide rail 183 is arranged on one side of the second plane reflector 8, and a second push rod 184 is arranged on the other side thereof. A belt 23 is arranged on the second push rod 184, and a rotating rod 22 is arranged at the other end of the belt 23. A fixed pulley 24 is arranged between the rotating rod 22 and the second push rod 184. The rotating rod 22, the second push rod 184, the fixed pulley 24 and the belt form a tensioning structure, and the belt 23 and the fixed pulley 24 realize the linkage control of the rotation of the rotating rod 22 and the second push rod 184.

[0099] The curvature of the connection interface of the rotating rod 22 needs to be calculated to ensure that the light path mirror sample is reflected and directed to the second plane reflector 8; to measure the rough surface, the elastic belt 23 is removed and the rotating rod 22 and the second push rod 184 are adjusted respectively.

[0100] The second push rod 184 penetrates the movable shell 15, and a part of the margin is arranged outside, and the position of the second plane reflector 8 can be directly adjusted outside by the second push rod 184. The second push rod 184 and the second plane reflector 8 can be movably connected or fixedly connected. When the second push rod 184 is movably connected, the second plane reflector 8 is moved while adjusting the angle between the second push rod 184 and the second plane reflector 8. When the second push rod 184 is fixedly connected, a corresponding long hole is arranged on the movable shell 15, and the second push rod 184 moves along the long hole to adjust the position of the second plane reflector 8.

[0101] The second slide rail 183 can be directly fixed on the moving shell 15 or can be fixed to the moving shell 15 by setting a second connecting column.

[0102] The hemispherical parabolic mirror 7 is hemispherical in shape. A bottom cover is disposed on the hemispherical parabolic mirror 7 . A second opening 12 is disposed on the bottom cover. The sample is located at the second opening 12 .

[0103] The bottom cover 10 is also provided with a fourth opening 21 located below the fixed plane reflector 2. The light path is reflected by the fixed plane reflector 2 and passes through the fourth opening 21 to the hemispherical parabolic mirror 7. The light is reflected by the hemispherical parabolic mirror 7 to the sample. The light is emitted by the sample and is again emitted to the hemispherical parabolic mirror 7. The light reflected by the hemispherical parabolic mirror 7 passes through the third opening 20 and is sent to the second plane reflector 7. The second plane reflector 7 reflects the light to the spectrum detector 9. The sample is directly fixed on the groove provided on the rotating rod 22. By rotating the rotating rod 22, the angle of the sample changes, so that data of different angles of the sample can be measured.

[0104] The spectrum detector 9 can be directly fixed on the moving shell 15 or can be fixed to the moving shell 15 by setting a third connecting column; a separate fixing device can also be set on the outside of the moving shell to fix the spectrum detector 9.

[0105] The light source 1 may be provided with a separate fixing device on the outside of the moving shell 15 for fixing the light source 1, or it may be directly fixed on the moving shell 15. In this case, a corresponding light channel is provided on the moving shell 15 to transmit light.

[0106] The wavelength ranges of the light source 1 and the spectrum receiver 9 correspond to each other so that all sample information can be received.

[0107] The included angles between the first plane reflector 3, the second plane reflector 8, the fixed plane reflector 2 and the main axis of the light are all 45°.

[0108] A method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle comprises the following steps:

[0109] (1) When the measured material has a smooth surface:

[0110] S1. Place the standard reflective gold plate at the focus of the hemispherical parabolic mirror and fix the plane reflector group at a specific position;

[0111] S2. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. G0 ;

[0112] S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ);

[0113] S4, rotating the sample placement rod to another angle, and driving the plane reflector assembly to move to the corresponding position through the belt, and repeating steps S2-S3;

[0114] S5. Take out the standard reflection specimen, place the sample to be tested at the focus of the hemispherical parabolic mirror, and fix the plane reflector assembly at a specific position;

[0115] S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ;

[0116] S7. Turn on the light source, keep the position of the sample to be tested and the plane reflector group unchanged, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ);

[0117] S8, rotating the sample placement rod to another angle, and driving the plane reflector assembly to move to the corresponding position through the belt, and repeating steps S6-S7;

[0118] S9. Calculate the directional emissivity of the material surface at each angle ε(λ, θ, T) = 1-ρ S (λ, θ, T) = 1 - ρ G (λ,θ,T)(S S (θ)-S S0 ) / (S G (θ)-S G0 ).

[0119] (2) When the measured material has a rough surface:

[0120] S1. Place the standard reflective gold plate at the focus of the hemispherical parabolic mirror and fix the plane reflector group at a specific position;

[0121] S2. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. G0 ;

[0122] S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ);

[0123] S4, remove the belt, rotate the sample placement rod to another angle, move the plane reflector to a different position, and repeat steps S2-S3;

[0124] S5. Take out the standard reflection specimen, place the sample to be tested at the focus of the hemispherical parabolic mirror, and fix the plane reflector assembly at a specific position;

[0125] S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ;

[0126] S7. Turn on the light source, keep the position of the sample to be tested and the plane reflector group unchanged, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ);

[0127] S8, remove the belt, rotate the sample placement rod to another angle, move the plane reflector to a different position, and repeat steps S6-S7;

[0128] S9. Calculate the directional emissivity of the material surface at each angle ε(λ, θ, T) = 1-ρ S (λ, θ, T) = 1 - ρ G (λ,θ,T)(S S (θ)-S S0 ) / (S G (θ)-S G0 ). Where ε(λ, θ, T) is the sample emissivity; ρ S (λ, θ, T) is the sample reflectance, ρ G is the reflectivity of the standard reflective gold plate, λ is the wavelength, θ is the angle between the incident light and the sample normal, T is the sample surface temperature, S S0 To place the sample, when the light source is turned off, the detector receives the radiation signal of the light source, S S (θ) is the radiation signal of the light source received by the detector when the sample is placed and the light source is turned on, S G0 When the light source is turned off, the standard reflection gold plate detector receives the radiation signal of the light source. G (θ) is the radiation signal of the light source received by the detector placed on a standard reflective gold plate when the light source is turned on.

[0129] Therefore, the present invention adopts the above-mentioned material room-temperature directional emissivity measurement device and method with adjustable incident angle, which can quickly and accurately measure the surface directional reflection intensity of the material at room temperature, and then calculate the emissivity according to Kirchhoff's law. The measurement time is short and it can be applicable to various smooth and rough material surfaces.

[0130] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that they can still modify or replace the technical solution of the present invention with equivalents, and these modifications or equivalent replacements cannot cause the modified technical solution to deviate from the spirit and scope of the technical solution of the present invention.

Claims

1. A device for measuring the directional emissivity of a material at room temperature with an adjustable incident angle, characterized in that: Including light source, The optical path system is arranged in the incident direction of the light source; The spectrum detector is arranged in the light path emission direction of the light path system; The optical path system includes a fixed plane reflector, a hemispherical parabolic mirror, and a second plane reflector that is movably arranged in the light transmission direction; The optical path system also includes an off-axis ellipsoidal spherical mirror fixedly arranged in the light transmission direction, a sample placement device fixedly arranged at the focus of the hemispherical parabolic mirror, a hemispherical parabolic mirror fixedly arranged in the light transmission direction, and an off-axis parabolic mirror; The off-axis ellipsoidal spherical mirror includes two focal points: a first focal point and a second focal point; The first focus of the off-axis ellipsoidal mirror coincides with the focus of the off-axis parabolic mirror, and the second focus of the off-axis ellipsoidal mirror coincides with the focus of the hemispherical parabolic mirror; A first opening is provided below the off-axis parabolic mirror, and the first focus is located in the first opening; The hemispherical parabolic mirror is provided with a bottom cover, the bottom cover is provided with a first opening and a second opening, and the second focus, the sample placement device and the sample are located in the second opening; The bottom cover is also provided with a third opening.

2. The device for measuring the directional emissivity of a material at room temperature with adjustable incident angle according to claim 1, characterized in that: A plane reflector group and a fixed plane reflector are movably arranged in the light transmission direction.

3. The device for measuring the directional emissivity of a material at room temperature with adjustable incident angle according to claim 2, characterized in that: The plane reflector group is provided with a first plane reflector and a second plane radiating mirror, the first plane reflector is arranged in front of the incident light source, the second plane reflector is arranged at the end of the fixed plane mirror, and the second plane reflector is located above the third opening.

4. The device for measuring the directional emissivity of a material at room temperature with adjustable incident angle according to claim 3, characterized in that: A first push rod is arranged on one side of the first plane reflecting mirror, and a first slide rail is arranged on the other side of the first plane reflecting mirror.

5. A device for measuring the directional emissivity of a material at room temperature with adjustable incident angle according to claim 1 or 3, characterized in that: A second push rod is arranged on the second plane reflecting mirror, and the second plane reflecting mirror is connected to a second slide rail arranged on one side thereof.

6. The device for measuring the directional emissivity of a material at room temperature with adjustable incident angle according to claim 5, characterized in that: A belt is arranged at one side of the second push rod, a rotating rod is arranged at the other end of the belt, a fixed pulley is arranged between the rotating rod and the second push rod, and the fixed pulley is connected to the belt; a sample is arranged at one end of the rotating rod.

7. The device for measuring the directional emissivity of a material at room temperature with adjustable incident angle according to claim 1, characterized in that: A fourth opening is arranged on the bottom cover below the fixed plane reflector.

8. A method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle, characterized in that: The following steps are involved: S1. Place the standard reflective gold plate at the second focus of the off-axis ellipsoidal mirror and fix the plane reflector assembly at a specific position; S2, turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal SG0 when there is no light source; S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ); S4, move the plane reflector assembly to another position and repeat step S3; S5, take out the standard reflective gold plate, place the sample to be tested at the first focus of the off-axis ellipsoidal mirror, and fix the plane reflector assembly at a specific position; S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ; S7. Turn on the light source, keep the position of the sample to be tested and the plane reflector group unchanged, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ); S8, move the plane reflector assembly to another position and repeat step S7; S9. Calculate the directional emissivity of the material surface at various angles ; In the formula, is the sample emissivity, is the sample reflectance, is the reflectivity of the standard reflective gold plate, is the wavelength, θ is the angle between the incident light and the sample normal, T is the sample surface temperature, S S0 To place the sample, when the light source is turned off, the detector receives the radiation signal of the light source, S S (θ) is the radiation signal of the light source received by the detector when the sample is placed and the light source is turned on, S G0 When the light source is turned off, the standard reflection gold plate detector receives the radiation signal of the light source. G (θ) is the radiation signal of the light source received by the detector placed on a standard reflective gold plate when the light source is turned on.

9. The method for measuring the directional emissivity of a material at room temperature with an adjustable incident angle according to claim 8, characterized in that: Can be replaced by the following steps, (1) When the measured material has a smooth surface: S1. Place the standard reflective gold plate at the focus of the hemispherical parabolic mirror and fix the plane reflector group at a specific position; S2. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. G0 ; S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ); S4, rotating the sample placement rod to another angle, and driving the plane reflector assembly to move to the corresponding position through the belt, and repeating steps S2-S3; S5. Take out the standard reflection specimen, place the sample to be tested at the focus of the hemispherical parabolic mirror, and fix the plane reflector group at a specific position; S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ; S7. Turn on the light source, keep the position of the sample to be tested and the plane reflector group unchanged, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ); S8, rotating the sample placement rod to another angle, and driving the plane reflector assembly to move to the corresponding position through the belt, and repeating steps S6-S7; S9. Calculate the directional emissivity of the material surface at various angles ; (2) When the measured material has a rough surface: S1. Place the standard reflective gold plate at the focus of the hemispherical parabolic mirror and fix the plane reflector group at a specific position; S2. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. G0 ; S3. Turn on the light source, keep the standard reflection gold plate and the plane reflector group in the same position, and the computer records the total signal S of the sample reflection and background radiation in this direction. G (θ); S4, remove the belt, rotate the sample placement rod to another angle, move the plane reflector to a different position, and repeat steps S2-S3; S5. Take out the standard reflection specimen, place the sample to be tested at the focus of the hemispherical parabolic mirror, and fix the plane reflector group at a specific position; S6. Turn off the light source, turn on the spectrum detector, and the computer records the background radiation signal S when there is no light source. S0 ; S7. Turn on the light source, keep the position of the sample to be tested and the plane reflector group unchanged, and the computer records the total signal S of the sample reflection in this direction and the background radiation S (θ); S8, remove the belt, rotate the sample placement rod to another angle, move the plane reflector to a different position, and repeat steps S6-S7; S9. Calculate the directional emissivity of the material surface at various angles .

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