Spectral radiance source and spectral radiance calibration method

Abstract

The present invention provides a spectral radiation brightness source and a spectral radiation brightness calibration method, which relate to the field of optical technology. The spectral radiation brightness source comprises: a first integrating sphere, a second integrating sphere, an optical fiber, a hollow connecting column, a baffle and a light source; the second integrating sphere is arranged inside the first integrating sphere and connected to the first integrating sphere through a hollow connecting column; the optical fiber is arranged in the hollow connecting column, one end of the optical fiber is connected to the light source, and the other end of the optical fiber is arranged at the light inlet on the second integrating sphere; the baffle is arranged between the light inlet and the second light outlet inside the second integrating sphere. The spectral radiation brightness source and the spectral radiation brightness calibration method provided by the present invention can improve the surface uniformity and angle uniformity of the light emitted by the spectral radiation brightness source through multiple reflections of the light without setting an aperture and / or increasing the volume of the integrating sphere, have little effect on the spectral radiation brightness of the spectral radiation brightness source, and can improve the Lambertian property of the light emitted by the spectral radiation brightness source.

Description

Technical Field

[0001] The present invention relates to the field of optical technology, and in particular to a spectral radiation brightness source and a spectral radiation brightness calibration method. Background Art

[0002] A spectral radiance source is an object or device that emits light radiation within a specific wavelength range. Radiance sources are often used as standard or reference light sources to calibrate and measure optical instruments. The uniformity of the light emitted by a spectral radiance source is important for the accuracy and reliability of optical instrument calibration and measurement.

[0003] The integrating sphere light source made by using the diffuse reflection characteristics of the integrating sphere is a commonly used spectral radiation brightness source. However, the uniformity of the light emitted by the traditional integrating sphere light source is difficult to meet the requirements of high-precision light radiation calibration.

[0004] Therefore, how to improve the uniformity of light emitted by a spectral radiation brightness source is a technical problem that needs to be solved urgently in this field. Summary of the invention

[0005] The present invention provides a spectral radiation brightness source and a spectral radiation brightness calibration method, which are used to solve the defect in the prior art that the uniformity of light emitted by a traditional integrating sphere light source is difficult to meet the requirements of high-precision light radiation calibration, and to improve the uniformity of light emitted by the spectral radiation brightness source.

[0006] The present invention provides a spectral radiation brightness source, comprising: a first integrating sphere, a second integrating sphere, an optical fiber, a hollow connecting column, a baffle and a light source;

[0007] The diameter of the first integrating sphere is greater than that of the second integrating sphere; the second integrating sphere is disposed inside the first integrating sphere and connected to the first integrating sphere through the hollow connecting column;

[0008] The first integrating sphere is provided with a first light exit hole; the second integrating sphere is provided with a light entrance hole and a second light exit hole; the light entrance hole and the hollow connecting column are coaxially arranged;

[0009] The optical fiber is arranged in the hollow connecting column, one end of the optical fiber is connected to the light source, and the other end of the optical fiber is arranged at the light inlet, and the optical fiber is used to guide the light emitted by the light source into the light inlet;

[0010] The baffle is disposed between the light inlet and the second light outlet inside the second integrating sphere, and is used to block the light entering the second integrating sphere through the light inlet from being directly emitted from the second light outlet;

[0011] The inner wall of the first integrating sphere, the inner wall and outer wall of the second integrating sphere, the baffle, and the inner wall and outer wall of the hollow connecting column are all covered with a diffuse reflection material layer.

[0012] According to a spectral radiation brightness source provided by the present invention, the center of the first integrating sphere coincides with the center of the second integrating sphere.

[0013] A spectral radiation brightness source provided by the present invention further includes: a third integrating sphere; the third integrating sphere is arranged inside the first integrating sphere and outside the second integrating sphere; the center of the third integrating sphere coincides with the center of the first integrating sphere;

[0014] The third integrating sphere is provided with a third light exit hole, and the third light exit hole is not coaxial with the first light exit hole and the second light exit hole;

[0015] The inner wall and the outer wall of the third integrating sphere are both covered with the diffuse reflection material layer.

[0016] According to a spectral radiation brightness source provided by the present invention, the light inlet hole and the second light outlet hole are coaxially arranged; and the baffle is arranged parallel to the light inlet hole.

[0017] According to a spectral radiation brightness source provided by the present invention, the arc between the third center point and the fourth center point on the third integrating sphere is determined based on the diameter of the third integrating sphere, the third center point is the center point of the third light output hole, and the fourth center point is the center point of the cross-section of the hollow connecting column and the third integrating sphere.

[0018] According to a spectral radiation brightness source provided by the present invention, the number of the third integrating spheres is one or more; when the number of the third integrating spheres is multiple, the third light exit holes on each of the third integrating spheres are not coaxial.

[0019] According to a spectral radiation brightness source provided by the present invention, the central angle corresponding to the split arc between the first center point and the second center point on the second integrating sphere is determined based on the diameter of the second integrating sphere, the first center point is the center point of the second light output hole, and the second center point is the center point of the light input hole.

[0020] According to a spectral radiation brightness source provided by the present invention, the baffle is arranged perpendicular to the tangent of the split arc.

[0021] According to a spectral radiation brightness source provided by the present invention, the first light exit hole and the hollow connecting column are coaxially arranged.

[0022] The present invention also provides a spectral radiance calibration method based on any of the spectral radiance sources described above, comprising:

[0023] Controlling the optical instrument to be calibrated to collect the spectral radiance of the light emitted from the first light exit hole of the spectral radiance source;

[0024] Based on the spectral radiation brightness value collected by the optical instrument to be calibrated and the known spectral radiation brightness value of the spectral radiation brightness source, a calibration result of the optical instrument to be calibrated is obtained.

[0025] The present invention provides a spectral radiation brightness source and a spectral radiation brightness calibration method. The spectral radiation brightness source includes a first integrating sphere, a second integrating sphere, an optical fiber, a hollow connecting column, a baffle and a light source. The light emitted by the light source is reflected multiple times inside the second integrating sphere, and then reflected multiple times inside the first integrating sphere before being emitted from a first light exit hole arranged on the first integrating sphere. Without the need to set an aperture at the light exit hole and / or increase the volume of the integrating sphere, the surface uniformity and angular uniformity of the light emitted by the spectral radiation brightness source can be improved through multiple reflections of the light. The spectral radiation brightness of the light emitted by the spectral radiation brightness source is less affected, the Lambertian property of the light emitted by the spectral radiation brightness source can be improved, and the uncertainty requirement of spectral radiation brightness calibration can be better met. The spectral radiation brightness source has a simple structure, low manufacturing cost, and a simple manufacturing process, and has broad application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0027] Figure 1 It is a structural schematic diagram of an integrating sphere light source with a built-in light source in the related art.

[0028] Figure 2 It is a structural schematic diagram of an integrating sphere light source using an external light source in the related art.

[0029] Figure 3 It is a structural schematic diagram of a cascade integrating sphere light source using a built-in light source in the related art.

[0030] Figure 4 It is a structural schematic diagram of a cascade integrating sphere light source using an external light source in the related art.

[0031] Figure 5 This is one of the structural schematic diagrams of the spectral radiation brightness source provided by the present invention.

[0032] Figure 6This is the second structural schematic diagram of the spectral radiation brightness source provided by the present invention.

[0033] Figure 7 It is a schematic flow chart of the spectral radiation brightness calibration method provided by the present invention.

[0034] Reference numerals:

[0035] 501, spectral radiation brightness source; 502, first integrating sphere; 503, second integrating sphere; 504, optical fiber; 505, hollow connecting column; 506, baffle; 507, light source; 508, first light exit hole; 509, light inlet hole; 510, second light exit hole; 511, diffuse reflection material layer; 512, supporting structure; 601, third integrating sphere; 602, third light exit hole. DETAILED DESCRIPTION

[0036] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In the description of the invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0038] In the description of the present application, the terms "first", "second", etc. are used to distinguish similar objects, and are not used to describe a specific order or sequence. It should be understood that the data used in this way can be interchangeable under appropriate circumstances, so that the embodiments of the present application can be implemented in an order other than those illustrated or described here, and the objects distinguished by "first", "second", etc. are usually a class, and the number of objects is not limited. For example, the first object can be one or more. In addition, in the description of the present application, "and / or" represents at least one of the connected objects, and the character " / " generally represents that the front and back associated objects are in an "or" relationship.

[0039] It should be noted that the integrating sphere light source made using the diffuse reflection characteristics of the integrating sphere is a commonly used spectral radiation brightness source. The integrating sphere light source usually consists of an integrating sphere and a built-in light source or an external light source. The inner wall of an ideal integrating sphere is coated with a uniform high reflectivity coating, and the inner wall of the integrating sphere is uniform everywhere. A baffle is set between the light source and the light outlet of the integrating sphere so that the light emitted by the light source cannot be directly emitted from the light outlet of the integrating sphere.

[0040] Figure 1 It is a structural schematic diagram of an integrating sphere light source with a built-in light source in the related art. Figure 2 FIG. 1 is a schematic diagram of the structure of an integrating sphere light source using an external light source in the related art. Figure 1 The structure of the traditional integrating sphere light source using an external light source is as follows Figure 2 shown.

[0041] It should be noted that Figure 1 and Figure 2 The baffles are made of the same spray material as the inner wall of the integrating sphere. The baffles can be rectangular or circular and are usually thinner. Due to the obstruction of the baffle, the light emitted by the light source cannot be directly emitted from the light outlet. Therefore, the light will be reflected multiple times inside the integrating sphere, making the radiation of the inner wall uniform, thereby ensuring the uniformity of the light emitted from the light outlet.

[0042] Figure 2 In the traditional integrating sphere light source shown, the light emitted by the external light source enters the integrating sphere in a direct manner rather than a diffuse manner. Figure 1 The traditional integrating sphere light source shown in the figure will destroy the diffuse reflection characteristics inside the integrating sphere because the built-in light source itself is not a diffuse reflection material. Therefore, in the related technology, a cascade structure can be used to further improve the uniformity of the light emitted from the light outlet of the integrating sphere light source.

[0043] Figure 3 It is a structural schematic diagram of a cascade integrating sphere light source using a built-in light source in the related art. Figure 4 FIG. 1 is a schematic diagram of the structure of a cascade integrating sphere light source using an external light source in the related art. Figure 3 The structure of the traditional cascade integrating sphere light source using an external light source is as follows Figure 4 shown.

[0044] Figure 3 and Figure 4 In the conventional cascade integrating sphere light source shown, two integrating spheres are used in series. The light emitted from the light outlet of the first integrating sphere has good Lambertian properties, then enters the second integrating sphere, and finally emits through the light outlet of the second integrating sphere.

[0045] However, on the one hand, the radiation characteristics of the light emitted by the traditional cascade integrating sphere light source will still be limited by the structure of the second integrating sphere. Although the baffle and the connecting column between the baffle and the inner wall are sprayed with the same high reflectivity coating as the inner wall, it will still have a certain impact on the diffuse reflection inside the integrating sphere. The connecting column is usually very thin and has a small surface area, while the surface area of ​​the baffle cannot be ignored, which to a certain extent damages the spherical symmetry structure of the integrating sphere, and ultimately affects the uniformity and Lambertian properties of the light emitted by the traditional cascade integrating sphere light source. At the same time, the processing cost of the integrating sphere light source is related to the size of the integrating sphere, and the cascade integrating sphere with two spheres connected is more expensive.

[0046] On the other hand, the ratio of the light radiation emitted from the first integrating sphere into the second integrating sphere to the light radiation entering the first integrating sphere is proportional to the ratio of the surface area of ​​the connection between the two integrating spheres to the inner surface area of ​​the first integrating sphere. Figure 1 and Figure 2 The traditional integrating sphere light source shown in Figure 3 and Figure 4 The spectral radiance of the light emitted by the conventional cascade integrating sphere light source shown will be greatly reduced.

[0047] In recent years, the field of optical remote sensing has increasingly higher requirements for the accuracy of optical instrument calibration and measurement, especially in global climate change research. In the study of the Earth's budget balance, it is necessary to accurately measure the total solar radiation received by the Earth and the radiation emitted by the Earth to space, so as to accurately predict the trend of Earth's climate change. At present, the international demand for the measurement uncertainty of solar radiation illuminance and Earth reflected radiation brightness is getting higher and higher, and the measurement uncertainty requirements of solar radiation illuminance and Earth reflected radiation brightness are as high as 0.01% and 0.1%.

[0048] The uncertainty of the calibration of the optical instrument's radiant brightness is determined by the stability and Lambertian properties of the integrating sphere light source and the characteristics of the optical instrument to be calibrated. According to current reports, the non-uniformity of the light emitted by the traditional integrating sphere light source is not less than 0.1%. At the same time, the angular non-uniformity of the light emitted by the traditional integrating sphere light source also affects the calibration of the radiant brightness of the optical instrument.

[0049] like Figure 3 and Figure 4 The volume of the conventional cascade integrating sphere light source shown is relatively large, and the non-uniformity of the light emitted by the conventional cascade integrating sphere light source is still not lower than 0.1%.

[0050] In order to improve the uniformity of the light emitted by the traditional integrating sphere light source, in principle, an aperture can only be set at the light outlet of the traditional integrating sphere light source to select only the light radiation from a specific area at the center of the light outlet. When the integrating sphere and the light outlet are large enough, and the selected measurement area is small enough, the non-uniformity of the light emitted by the traditional integrating sphere light source can be achieved to be less than 0.1%.

[0051] However, the larger the integrating sphere, the smaller the light radiation value of the light emitted by the integrating sphere light source, and the more processing costs and power waste of the light source. When the spectral radiation brightness of the light emitted by the integrating sphere light source is too weak, the light emitted by the integrating sphere light source cannot meet the requirements of the optical instrument radiation brightness calibration. The angular uniformity test of the light emitted by the integrating sphere light source also has similar problems.

[0052] Therefore, it is difficult to ensure that the non-uniformity of the light emitted by the traditional integrating sphere light source is less than 0.1% based on the characteristics of the traditional integrating sphere light source itself. Therefore, how to improve the uniformity of the light emitted by the spectral radiation brightness source is a technical problem that needs to be solved urgently in this field.

[0053] In this regard, the present invention provides a spectral radiation brightness source that can achieve high uniformity. The spectral radiation brightness source provided by the present invention is composed of a first integrating sphere, a second integrating sphere, a hollow connecting column, an optical fiber and a light source. The first integrating sphere and the second integrating sphere are connected by a hollow connecting column. The hollow connecting column has good rigidity and can support the first integrating sphere and the second integrating sphere. The optical fiber passes through the hollow connecting column, one end of which is connected to the light source and the other end is arranged at the light inlet on the second integrating sphere. After the light radiation emitted by the light source is introduced through the optical fiber, it enters the first integrating sphere from the second light outlet on the second integrating sphere, and finally outputs the light radiation through the first integrating sphere.

[0054] Combine the following Figure 5-Figure 6 The spectral radiance source provided by the present invention is described.

[0055] Figure 5 This is one of the structural schematic diagrams of the spectral radiation brightness source provided by the present invention. Figure 5 As shown, the spectral radiation brightness source 501 provided by the present invention includes: a first integrating sphere 502, a second integrating sphere 503, an optical fiber 504, a hollow connecting column 505, a baffle 506 and a light source 507;

[0056] The diameter of the first integrating sphere 502 is larger than that of the second integrating sphere 503; the second integrating sphere 503 is disposed inside the first integrating sphere 502 and connected to the first integrating sphere 502 through a hollow connecting column 505;

[0057] The first integrating sphere 502 is provided with a first light exit hole 508; the second integrating sphere 503 is provided with a light inlet hole 509 and a second light exit hole 510; the light inlet hole 509 and the hollow connecting column 505 are coaxially arranged;

[0058] The optical fiber 504 is disposed in the hollow connecting column 505, one end of the optical fiber 504 is connected to the light source 507, and the other end of the optical fiber 504 is disposed at the light inlet 509, and the optical fiber 504 is used to guide the light emitted by the light source 507 into the light inlet 509;

[0059] The baffle 506 is disposed between the light inlet hole 509 and the second light outlet hole 510 inside the second integrating sphere 503, and is used to block the light entering the second integrating sphere 503 through the light inlet hole 509 from being directly emitted from the second light outlet hole 510;

[0060] The inner wall of the first integrating sphere 502 , the inner wall and outer wall of the second integrating sphere 503 , the baffle 506 , and the inner wall and outer wall of the hollow connecting column 505 are all covered with a diffuse reflection material layer 511 .

[0061] Specifically, the light emitted by the light source 507 can be emitted into the second integrating sphere 503 through the optical fiber 504 disposed in the hollow connecting column 505 and the light inlet hole 509 disposed on the second integrating sphere 503 .

[0062] The baffle 506 disposed between the light inlet 509 and the second light outlet 510 can block the light entering the second integrating sphere 503 through the light inlet 509 from being directly emitted from the second light outlet 510, so that the light entering the second integrating sphere 503 can enter the first integrating sphere 502 through the second light outlet 510 disposed on the second integrating sphere 503 after multiple reflections in the second integrating sphere 503.

[0063] The light emitted from the second light emitting hole 510 into the first integrating sphere 502 may be emitted through the first light emitting hole 508 disposed on the first integrating sphere 502 after being reflected multiple times in the first integrating sphere 502 .

[0064] Optionally, if the radius of the first integrating sphere 502 is R and the radius of the second integrating sphere 503 is r, then the angle θ<2arcsin(r / R). Usually, the ratio of the second integrating sphere to the first integrating sphere is set to be less than 1:3, that is, θ<39°.

[0065] Optionally, the light source 507 in the embodiment of the present invention may include a laser, a plasma light source, an LED lamp, a bromine tungsten lamp, etc.

[0066] It should be noted that the spectral radiance of the light emitted by the light source 507 in the embodiment of the present invention may be determined based on actual needs. The spectral radiance of the light emitted by the light source 507 in the embodiment of the present invention is not specifically limited.

[0067] Optionally, the baffle 506 in the embodiment of the present invention may be circular or square. The size of the baffle 506 may be twice the diameter of the hollow connecting column, and the distance from the light inlet is equal to the radius of the hollow connecting column. The size of the hollow connecting column may be twice the diameter of the optical fiber (the outer envelope of the optical fiber is usually 125 μm, and twice is a diameter of 250 μm).

[0068] For the first integrating sphere with a diameter of 10 cm, the diameter of the second integrating sphere is 1 / 3 of the diameter of the first integrating sphere, and the cross-sectional area of ​​the hollow connecting column is π×0.025 cm×5 cm×2 / 3=0.26 cm 2 In traditional integrating sphere light sources, excluding the connecting parts of the baffle, the baffle diameter is usually 2 cm, and the baffle area is π×1cm×1cm=3.14159cm 2 The spectral radiation brightness source provided by the present invention has a significantly smaller impact on the uniformity of the sphere.

[0069] It should be noted that the diffuse reflection material in the embodiment of the present invention refers to a material that can cause light to be reflected irregularly on its surface. The characteristic of the diffuse reflection material is that the reflected light is evenly distributed in all directions without forming obvious specular reflection or light spots. In the embodiment of the present invention, diffuse reflection paint can be used to form a diffuse reflection material layer 511 on the inner wall of the first integrating sphere 502, the inner wall and outer wall of the second integrating sphere 503, the baffle 506, and the inner wall and outer wall of the hollow connecting column 505.

[0070] It should be noted that the reflectivity of the diffuse reflection material layer 511 in the embodiment of the present invention may be determined based on actual needs, and the reflectivity of the diffuse reflection material layer 511 is not limited in the embodiment of the present invention.

[0071] The spectral radiation brightness source in the embodiment of the present invention includes a first integrating sphere, a second integrating sphere, an optical fiber, a hollow connecting column, a baffle and a light source. The light emitted by the light source is reflected multiple times inside the second integrating sphere, and then reflected multiple times inside the first integrating sphere before being emitted from a first light exit hole arranged on the first integrating sphere. Without the need to set an aperture at the light exit hole and / or increase the volume of the integrating sphere, the surface uniformity and angular uniformity of the light emitted by the spectral radiation brightness source can be improved through multiple reflections of the light. The spectral radiation brightness of the light emitted by the spectral radiation brightness source has little effect, the Lambertian properties of the light emitted by the spectral radiation brightness source can be improved, and the uncertainty requirements of the spectral radiation brightness calibration can be better met. The spectral radiation brightness source has a simple structure, low manufacturing cost, and simple manufacturing process, and has broad application prospects.

[0072] As an optional embodiment, the center of the first integrating sphere 502 coincides with the center of the second integrating sphere 503 .

[0073] In the spectral radiation brightness source in the embodiment of the present invention, the center of the first integrating sphere coincides with the center of the second integrating sphere, which can better preserve the spherical symmetry of the diffuse reflection inside the integrating sphere and further improve the uniformity of the light emitted by the spectral radiation brightness source.

[0074] As an optional embodiment, the center angle corresponding to the arc between the first center point and the second center point on the second integrating sphere 503 is determined based on the diameter of the third integrating sphere, the first center point is the center point of the second light output hole 510, and the second center point is the center point of the light input hole 509.

[0075] As an optional embodiment, the baffle 506 is disposed perpendicular to the tangent line of the split arc.

[0076] It should be noted that the spectral radiation brightness source in the embodiment of the present invention further includes a support structure 512. The support structure 512 is connected to the first integrating sphere 502 and is used to support the first integrating sphere 502.

[0077] In the spectral radiation brightness source in the embodiment of the present invention, the central angle corresponding to the split arc between the center point of the first light exit hole and the center point of the light entrance hole is determined based on the diameter of the first integrating sphere, so that the second integrating sphere has a certain internal space and can also act as a baffle, which can make the light more fully reflected in the second integrating sphere and the first integrating sphere, and can further improve the uniformity of the light emitted by the spectral radiation brightness source. The baffle is arranged perpendicular to the tangent of the above-mentioned split arc, which can better block the light entering the second integrating sphere from the light entrance hole from being directly emitted from the second light exit hole, thereby better ensuring that the spectral radiation brightness of the light emitted by the spectral radiation brightness source is not reduced.

[0078] Figure 6This is the second structural schematic diagram of the spectral radiation brightness source provided by the present invention. Figure 6 As shown, the spectral radiation brightness source 501 provided by the present invention further includes: a third integrating sphere 601; the third integrating sphere 601 is arranged inside the first integrating sphere 502 and outside the second integrating sphere 503; the center of the third integrating sphere 601 coincides with the center of the first integrating sphere 502;

[0079] The third integrating sphere 601 is provided with a third light exit hole 602, and the third light exit hole 602 is not coaxial with the first light exit hole 508 and the second light exit hole 510;

[0080] The inner wall and the outer wall of the third integrating sphere 601 are both covered with a diffuse reflection material layer 511 .

[0081] Specifically, in order to further improve the uniformity of the light emitted by the spectral radiation brightness source 501 provided by the present invention, a third integrating sphere 601 is added between the first integrating sphere 502 and the second integrating sphere 503 in the embodiment of the present invention.

[0082] like Figure 6 As shown, the light emitted by the light source 507 can be emitted into the second integrating sphere 503 through the optical fiber 504 disposed in the hollow connecting column 505 and the light inlet hole 509 disposed on the second integrating sphere 503 .

[0083] The baffle 506 disposed between the light inlet 509 and the second light outlet 510 can block the light entering the second integrating sphere 503 through the light inlet 509 from being directly emitted from the second light outlet 510, so that the light entering the second integrating sphere 503 can enter the third integrating sphere 601 through the second light outlet 510 disposed on the second integrating sphere 503 after multiple reflections in the second integrating sphere 503.

[0084] The light emitted from the second light exit hole 510 into the third integrating sphere 601 may enter the first integrating sphere 502 through the third light exit hole 602 disposed on the third integrating sphere 601 after being reflected multiple times inside the third integrating sphere 601 .

[0085] The light emitted from the second light emitting hole 510 into the first integrating sphere 502 may be emitted through the first light emitting hole 508 disposed on the first integrating sphere 502 after being reflected multiple times in the first integrating sphere 502 .

[0086] Optionally, the radius of the third integrating sphere 601 is less than or equal to one third of the radius of the first integrating sphere, and the radius of the second integrating sphere is one third of the radius of the third integrating sphere.

[0087] It should be noted that Figure 5 and Figure 6 The blue area in represents the diffuse reflection material layer 511.

[0088] As an optional embodiment, the number of the third integrating spheres 601 is one or more; when the number of the third integrating spheres 601 is multiple, the third light exit holes 602 on each of the third integrating spheres 601 are not coaxial.

[0089] The spectral radiation brightness source in the embodiment of the present invention also includes a third integrating sphere. The light emitted by the light source is reflected multiple times in the second integrating sphere, the third integrating sphere and the first integrating sphere in sequence, and then emitted from the first light exit hole arranged on the first integrating sphere. By increasing the reflection of the light inside the integrating sphere, the uniformity of the light emitted by the spectral radiation brightness source can be further improved, and the Lambertian properties of the light emitted by the spectral radiation brightness source can be further improved.

[0090] As an optional embodiment, the light inlet hole 509 and the second light outlet hole 510 are coaxially arranged; and the baffle 506 is arranged parallel to the light inlet hole 509 .

[0091] The spectral radiation brightness source in the embodiment of the present invention, the centers of the first integrating sphere, the second integrating sphere and the third integrating sphere coincide with each other, which can better retain the spherical symmetry of the diffuse reflection inside the integrating spheres, and can further improve the uniformity of the light emitted by the spectral radiation brightness source. The baffle is arranged parallel to the light inlet, which can better block the light entering the second integrating sphere through the light inlet from being directly emitted from the second light outlet, thereby better ensuring that the spectral radiation brightness of the light emitted by the spectral radiation brightness source does not decrease.

[0092] As an optional embodiment, the central angle corresponding to the arc between the third center point and the fourth center point on the third integrating sphere 601 is determined based on the diameter of the third integrating sphere 601, the third center point is the center point of the third light output hole 602, and the fourth center point is the center point of the cross-section of the hollow connecting column 505 and the third integrating sphere 601.

[0093] As an optional embodiment, the first light exit hole 508 and the hollow connecting column 505 are coaxially arranged.

[0094] In the spectral radiation brightness source in the embodiment of the present invention, the central angle corresponding to the arc between the center point of the third light exit hole and the center point of the cross section of the hollow connecting column and the third integrating sphere is less than 39°, and the first light exit hole and the hollow connecting column are coaxially arranged, so that the second integrating sphere has a certain internal space and can also act as a baffle, which can make the light more fully reflected in the second integrating sphere and the first integrating sphere, and can further improve the uniformity of the light emitted by the spectral radiation brightness source.

[0095] Figure 7is a flow chart of the spectral radiation brightness calibration method provided by the present invention. The spectral radiation brightness calibration method provided by the present invention is implemented based on the above-mentioned spectral radiation brightness source 501. Figure 7 As shown, the method includes: step 701, controlling the optical instrument to be calibrated to collect the spectral radiance of the light emitted by the first light exit hole 508 of the spectral radiance source 501;

[0096] Step 702: Based on the spectral radiance brightness value collected by the optical instrument to be calibrated and the known spectral radiance brightness value of the spectral radiance brightness source 501, a calibration result of the optical instrument to be calibrated is obtained.

[0097] The embodiment of the present invention controls the optical instrument to be calibrated to collect the spectral radiation brightness of the light emitted by the first light exit hole of the spectral radiation brightness source, and then obtains the calibration result of the optical instrument to be calibrated based on the spectral radiation brightness value collected by the optical instrument to be calibrated and the known spectral radiation brightness value of the spectral radiation brightness source. Based on the spectral radiation brightness source provided by the present invention, more accurate and reliable spectral radiation brightness calibration can be achieved.

[0098] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A spectral radiance source, characterized in that: include: A first integrating sphere, a second integrating sphere, an optical fiber, a hollow connecting column, a baffle, and a light source; The diameter of the first integrating sphere is larger than that of the second integrating sphere; The second integrating sphere is disposed inside the first integrating sphere and connected to the first integrating sphere through the hollow connecting column; The first integrating sphere is provided with a first light exit hole; the second integrating sphere is provided with a light entrance hole and a second light exit hole; the light entrance hole and the hollow connecting column are coaxially arranged; The optical fiber is arranged in the hollow connecting column, one end of the optical fiber is connected to the light source, and the other end of the optical fiber is arranged at the light inlet, and the optical fiber is used to guide the light emitted by the light source into the light inlet; The baffle is disposed between the light inlet and the second light outlet inside the second integrating sphere, and is used to block the light entering the second integrating sphere through the light inlet from being directly emitted from the second light outlet; The inner wall of the first integrating sphere, the inner wall and outer wall of the second integrating sphere, the baffle, and the inner wall and outer wall of the hollow connecting column are all covered with a diffuse reflection material layer.

2. The spectral radiance source according to claim 1, characterized in that The center of the first integrating sphere coincides with the center of the second integrating sphere.

3. The spectral radiance source according to claim 2, characterized in that: Also includes: a third integrating sphere; the third integrating sphere being disposed inside the first integrating sphere and outside the second integrating sphere; The center of the third integrating sphere coincides with the center of the first integrating sphere; The third integrating sphere is provided with a third light exit hole, and the third light exit hole is not coaxial with the first light exit hole and the second light exit hole; The inner wall and the outer wall of the third integrating sphere are both covered with the diffuse reflection material layer.

4. The spectral radiance source according to claim 3, characterized in that: The light inlet hole and the second light outlet hole are coaxially arranged; the baffle is arranged parallel to the light inlet hole.

5. The spectral radiance source according to claim 4, characterized in that: The central angle corresponding to the split arc between the third center point and the fourth center point on the third integrating sphere is determined based on the diameter of the third integrating sphere, the third center point is the center point of the third light output hole, and the fourth center point is the center point of the cross section of the hollow connecting column and the third integrating sphere.

6. The spectral radiance source according to claim 3, characterized in that: The number of the third integrating spheres is one or more. When there are multiple third integrating spheres, the third light exit holes on each of the third integrating spheres are not coaxial.

7. The spectral radiance source according to claim 1, characterized in that: The central angle corresponding to the split arc between the first center point and the second center point on the second integrating sphere is determined based on the diameter of the second integrating sphere, the first center point is the center point of the second light output hole, and the second center point is the center point of the light input hole.

8. The spectral radiance source according to claim 7, characterized in that The baffle is arranged perpendicular to a tangent line of the split arc.

9. The spectral radiance source according to any one of claims 1 to 8, characterized in that: The first light exit hole and the hollow connecting column are coaxially arranged.

10. A spectral radiance calibration method based on the spectral radiance source according to any one of claims 1 to 9, characterized in that: include: Controlling the optical instrument to be calibrated to collect the spectral radiance of the light emitted from the first light exit hole of the spectral radiance source; Based on the spectral radiation brightness value collected by the optical instrument to be calibrated and the known spectral radiation brightness value of the spectral radiation brightness source, a calibration result of the optical instrument to be calibrated is obtained.

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