A sunlight simulator

Abstract

This invention relates to a sunlight simulator, characterized by: a reflector having a parabolic inner reflecting surface, the parabola of which has an axis of symmetry and a focal point; and a polyhedral light source comprising a polyhedral support and a main light-emitting element, the polyhedral support having a main mounting surface for mounting the main light-emitting element, all of which are located near the focal point of the parabolic inner reflecting surface, and an angle between the main mounting surface and the axis of symmetry. The advantages of this invention are: by adjusting the angles of the reflector, the polyhedral light source, and the main and auxiliary light-emitting elements, the light intensity difference in different areas within the reflector is small, avoiding the impact of light intensity distribution differences on the simulated sunlight effect; and the design of the blue light chip located on the front mounting surface allows the sunlight simulator to achieve a sky color simulation effect close to or the same as that of a Rayleigh scattering panel without requiring a Rayleigh scattering panel.

Description

Technical Field

[0001] This invention relates to a light source, and more particularly to a sunlight simulator. Background Technology

[0002] As people's living standards improve, the requirements for artificial lighting systems are also increasing. Lighting systems that simulate outdoor sunlight can significantly improve users' visual experience and have a promising market prospect.

[0003] The solar-simulated lighting system primarily utilizes the Rayleigh scattering principle. Visible light emitted from the light source, after passing through a Rayleigh scattering plate, forms a light similar to the pale blue light seen in the Earth's atmosphere under clear skies. To guide the observer's perception of the light source as originating from the distant sun, the uniformity of brightness in the light source within the lighting system is crucial.

[0004] Currently known sunlight simulation lighting systems typically employ a light source module composed of several chips with lenses or reflectors, with the light-emitting surfaces of the chips facing the openings of the lenses or reflectors. The emitted light is refracted by the lenses or reflectors, resulting in significant differences in light intensity at the center and periphery of each chip. Multiple chips can even be clearly observed, severely impacting the effectiveness of sunlight simulation. Reducing the central brightness requires multiple diffusers, which significantly increases the product's size and limits its usability within indoor spaces. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a solar simulator with small size and high light uniformity.

[0006] To solve the above-mentioned technical problems, the technical solution of the present invention is as follows: a sunlight simulator, the innovation of which is: a reflector having a parabolic inner reflecting surface, the parabola of which has an axis of symmetry and a focal point; a polyhedral light source including a polyhedral support and a main light-emitting element, the polyhedral support having at least two main mounting surfaces for mounting the main light-emitting element, both of which are located inside the reflector and near the focal point of the parabolic inner reflecting surface, and an angle exists between the main mounting surfaces and the axis of symmetry; the main light-emitting element for simulating sunlight is mounted on the main mounting surfaces, such that the main light emission direction of the main light-emitting element is towards the inner reflecting surface of the reflector while being neither parallel nor perpendicular to the axis of symmetry.

[0007] The parabolic shape in this invention is a standard parabolic equation curve or a curve approximating the standard parabolic equation. The approximate curve is a hyperbola. When the light source is located near the focal point of the hyperbola, the light emitted by the main light-emitting element, after being reflected by the reflector, has an angle within ±15° with the axis of symmetry of the inner reflector of the parabolic shape. For the main mounting surface, there are at least two, and it is preferable that they are arranged in a ring or rectangular array or symmetrically distributed with the axis of symmetry as the axis of symmetry.

[0008] Preferably, the polyhedral support further includes a front mounting surface and an auxiliary light-emitting element disposed on the front mounting surface, wherein the main light emission direction of the auxiliary light-emitting element faces away from the inner reflective surface of the reflector.

[0009] Preferably, the auxiliary light-emitting element includes a blue light chip for simulating and supplementing the color of the sky, with an emission wavelength range of 390-500nm.

[0010] Preferably, the auxiliary light-emitting element includes a solar light-emitting chip for simulating sunlight, and the luminous power W of the solar light-emitting chip is... 太 Less than the luminous power W of the main light-emitting element 主 .

[0011] Preferably, the auxiliary light-emitting element includes a blue light chip for simulating and supplementing the color of the sky and a solar light-emitting chip for simulating sunlight, and the luminous power W of the solar light-emitting chip is... 太 Less than the luminous power W of the main light-emitting element 主 .

[0012] Preferably, the luminous power of the solar-emitting chip and the luminous power of the main luminous element satisfy: 0 < W 太 ≤2d / D*W 主 D is the width of the parabolic opening of the reflective surface inside the reflector, and d is the width of the front prism surface in the direction of the parabolic opening width.

[0013] Preferably, the polyhedral support is a triangular prism structure with an isosceles triangle cross-section. The two prism surfaces where the legs of the isosceles triangle are located are the main mounting surfaces, and the prism surface where the base of the isosceles triangle is located is the front mounting surface.

[0014] Preferably, the polyhedral support is a regular square pyramid structure, with the surface where the side of the pyramid on the polyhedral support is located being the main mounting surface, and the surface where the bottom of the pyramid on the polyhedral support is located being the front mounting surface.

[0015] Preferably, the angle between the two main mounting surfaces of the polyhedral support and the axis of symmetry of the parabolic inner reflector is α, and the light intensities of the two main light-emitting elements on the two main mounting surfaces in the direction normal to their own light-emitting surfaces are I and I, respectively. 10 I 20 , and I 10 =I 20 ;

[0016] The region near the axis of symmetry of the inner reflecting surface where the emitted rays from the two main light-emitting elements coincide is designated as the superposition region. The region between the normal direction of the main light-emitting element's own light-emitting surface and the superposition region is designated as the inner single-beam region. The region between the normal direction of the main light-emitting element's own light-emitting surface and the opening edge of the inner reflecting surface is designated as the outer single-beam region. To ensure that the light intensity difference between the regions on the inner reflecting surface does not exceed 15%, the following conditions must be met:

[0017] Light intensity I in the limited single-light region 1β and I 2β It satisfies the following relationship:

[0018] Formula 1: I 1β =I 10 *cos m β≥0.85I 10 I 2β =I 20 *cos m β≥0.85I 20 ; 1≤m≤30, β is the angle between the light emitted from the main light source on this side and the normal direction of the light-emitting surface of the main light source on this side, and m is the maximum light emission angle coefficient of the main light source;

[0019] The light intensity of the superposition region is I 叠加 It satisfies the following relationship:

[0020] I 叠加 =I 1γ +I 2γ =I 10 *cos m γ+I 20 *cos m (180°-γ-2α); γ is one of them.

[0021] The angle between the light emitted from the main light source on one side and the normal direction of the light-emitting surface of the main light source on that side;

[0022] The light intensity of the inner reflecting surface located on the axis of symmetry satisfies the following relationship:

[0023] Formula 2: 0.85I 10 ≤I 叠加 =I 1γ +I 2γ =2*I 10 *cos m (90°-α)≤1.15I 10 ;

[0024] The angles between the emitted light rays from the superposition zone and the emitted light rays from the inner single-beam zone and the normal to the light-emitting surface of the main light-emitting element on that side satisfy the following relationship:

[0025] Formula 3: γ>90°-α.

[0026] More specifically, it also includes a beam-splitting collimator that covers the end opening of the reflector and is a honeycomb structure composed of a number of precisely arranged columnar light guides.

[0027] The advantages of this invention are as follows: A polyhedral light source with a polyhedral support replaces the traditional light-emitting chip, with its light-emitting surface tilted away from the opening of the reflector, preventing direct emission of the light source. By adjusting the angles of the reflector, the polyhedral light source, and the main and auxiliary light-emitting components, the light intensity difference between different areas within the reflector is minimized. This not only avoids the impact of varying light intensity distribution on the simulated sunlight effect but also avoids the problem of an excessively large overall size for the solar simulator due to the need for a diffuser plate to adjust the light intensity. The design of the blue light chip located on the front mounting surface allows the solar simulator to achieve a sky color simulation effect close to or the same as that of a Rayleigh scattering panel without requiring a Rayleigh scattering plate. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the solar simulator structure of the present invention.

[0029] Figure 2 This is a schematic diagram of one form of the reflector structure of the present invention.

[0030] Figure 3 This is a schematic diagram of the first type of polyhedral support of the present invention inside the reflector.

[0031] Figure 4 This is a schematic diagram of the second type of polyhedral support of the present invention inside the reflector.

[0032] Figure 5 This is a schematic diagram of the third type of polyhedral support of the present invention inside the reflector.

[0033] Figure 6 This is a diagram showing the relationship between the angle of the main mounting surface of the polyhedral bracket and the light pattern of the main light-emitting element in this invention. Detailed Implementation

[0034] The solar simulator of the present invention is used to simulate sunlight exposure in indoor areas, such as... Figure 1 As shown, including

[0035] Reflector 1, which has a parabolic inner reflecting surface, the parabola of which has an axis of symmetry and a focus;

[0036] The polyhedral light source 2 includes a polyhedral support 21 and a main light-emitting element 22. The polyhedral support has at least two main mounting surfaces 21a for mounting the main light-emitting element. The main mounting surfaces 21a are both located inside the reflector 1 and near the focal point of the parabolic inner reflective surface. There is an angle between the main mounting surfaces and the axis of symmetry. The main light-emitting element 22 for simulating sunlight is attached to the main mounting surfaces 21a, and the main light emission direction of the main light-emitting element 22 is directed toward the inner reflective surface of the reflector while being neither parallel nor perpendicular to the axis of symmetry.

[0037] In this invention

[0038] More specifically, for the parabolic inner reflective surface: the parabola in the parabola is a curve of the standard parabola equation or a curve of an approximate standard parabola equation. The approximate curve is a hyperbola. When the light source is located near the focal point of the hyperbola, the angle between the light emitted by the main light-emitting element and the axis of symmetry of the parabolic inner reflective surface after reflection by the reflector is within ±15°.

[0039] More specifically regarding the spatial structure of the reflector: the reflector can be approximated as a dome-shaped structure composed of four sides, such as... Figure 2 As shown, a parabolic inner reflecting surface 11 serves as two symmetrical sides of the reflector, and two relatively parallel and symmetrically arranged side planes 12 serve as two other symmetrical sides; or a parabolic inner reflecting surface 11 serves as two symmetrical sides of the reflector, and two symmetrically arranged arcuate surfaces serve as two other symmetrical sides.

[0040] For polyhedral light sources, more specifically: for Figure 2 For reflectors in a given configuration, a symmetrical arrangement of two main mounting surfaces is suitable. For reflectors that combine a parabolic inner reflecting surface with an arc-shaped surface, a four-main mounting surface structure is suitable, with the four main mounting surfaces arranged in a ring or rectangular array around the axis of symmetry.

[0041] In some embodiments, the polyhedral support 21 further includes a front mounting surface 21b and an auxiliary light-emitting element 23 disposed on the front mounting surface 21b, wherein the main light emission direction of the auxiliary light-emitting element 23 is opposite to the inner reflective surface of the reflector.

[0042] In some specific embodiments, the front mounting surface 21b and the auxiliary light-emitting element 23 thereon are located inside the reflector 1:

[0043] like Figure 3 As shown, the polyhedral support 21 is a triangular prism structure with an isosceles triangle cross-section. The two prism surfaces that define the legs of the isosceles triangle are the main mounting surfaces 21a, and the prism surface that defines the base of the isosceles triangle is the front mounting surface 21b perpendicular to the axis of symmetry.

[0044] The two ends of the triangular prism structure extend to the two sides of the corresponding reflector 1 for fixation, or extend all the way through all reflectors 1. In this structure, the reflector adopts... Figure 2 The structure is relatively good.

[0045] like Figure 4 As shown, the polyhedral support 21 is a regular square pyramid structure. The surface on which the pyramidal side of the polyhedral support 21 is located is the main mounting surface 21a, and the surface on which the pyramidal base of the polyhedral support is located is the front mounting surface 21b perpendicular to the axis of symmetry.

[0046] The polyhedral support 21 also includes a connecting segment 211 that connects the vertex of the regular square pyramid structure to the vertex of the parabolic inner reflective surface of the reflector 1, so as to position the main light-emitting element 22 and the auxiliary light-emitting element 23 within the reflector 1. In this structure, the reflector adopts... Figure 3 The structure is relatively good.

[0047] In some other specific embodiments, the front mounting surface 21b and the auxiliary light-emitting element 23 thereon are located outside the reflector 1:

[0048] like Figure 5 As shown, the polyhedral support 21 includes a regular square pyramid structure located inside each reflector 1, an extension section 212 extending from the reflector 1 along the axis of symmetry, and a connecting section (not shown in the figure) connecting each corresponding reflector extension section. The surface where the pyramidal side of the polyhedral support is located is the main mounting surface 21a, and the surface where the outer end of the extension section 212 is located is the front mounting surface 21b.

[0049] Of course, it should be noted that the front mounting surface is not limited to being perpendicular to the axis of symmetry. The front mounting surface can be either a planar form or a polyhedral form of the main mounting surface.

[0050] Currently available sunlight simulators all require Rayleigh scattering panels to simulate the effect of sunlight in a blue sky. The light emitted from the light source uses the Rayleigh scattering panel to form the color of the blue sky. Compared to ordinary scattering panels, Rayleigh scattering panels provide a better simulation of a blue sky, but they are more expensive to manufacture and the sky color is fixed and monotonous.

[0051] Therefore, in some embodiments, the auxiliary light-emitting element 23 includes a blue light chip for simulating and supplementing the sky color, emitting wavelengths in the range of 390-500 nm. In this way, the light emitted by the blue light chip can be used to supplement the non-Rayleigh scattering panel simulating a blue sky, achieving a sky color simulation effect close to that of a Rayleigh scattering panel, thus reducing costs. Furthermore, this structural design can also be used with a Rayleigh scattering panel, allowing for the presentation of different states of sky blue by adjusting the power of the blue light chip.

[0052] To fully reproduce the simulated effect of sunlight, in one specific embodiment, the main light-emitting element 22 includes a violet light chip and a blue light chip. The violet light chip is coated with blue phosphor at least on its top surface, and the blue light chip is coated with green and red phosphors at least on its top surface. Preferably, the CSP chip consists of a violet light chip coated with blue phosphor, and a blue light chip coated with green and red phosphors.

[0053] In another specific embodiment, the main light-emitting element 22 includes a violet light chip, a first blue light chip, and a second blue light chip. The violet light chip is coated with blue phosphor at least on its top surface, the first blue light chip is coated with green phosphor at least on its top surface, and the second blue light chip is coated with green phosphor and red phosphor at least on its top surface. Preferably, the violet light chip, the first blue light chip, and the second blue light chip are CSP chips.

[0054] When simulating the parallel light effect of sunlight, the light emitted from the prism-shaped light source is reflected by the reflector and exits almost parallel. However, due to the obstruction of the polyhedral support 21, very little light exits from the vicinity of the symmetry axis of the reflecting surface inside the reflector, thus creating a visual illusion. opposite The problem of dark areas near the axis of symmetry of the shroud.

[0055] Therefore, in some embodiments, the auxiliary light-emitting element 23 includes a solar light-emitting chip for simulating sunlight.

[0056] Of course, considering the difference in light intensity, the luminous power (W) of the solar-emitting chip... 太 The required luminous power (W) is less than that of the main light-emitting element. 主 The luminous power of the solar-emitting chip and the luminous power of the main light-emitting element: 0 < W 太 ≤2d / D*W 主 D is the width of the parabolic opening of the reflective surface inside the reflector, and d is the width of the front prism surface in the direction of the parabolic opening width. In this way, the difference in light intensity in all areas within the opening of the reflector is small and not easily perceived by the observer.

[0057] In a more preferred embodiment, the auxiliary light-emitting element 23 may simultaneously include a blue light chip for simulating and supplementing the color of the sky, and a sunlight-emitting chip for simulating sunlight, wherein the luminous power W of the sunlight-emitting chip is... 太 Less than the luminous power W of the main light-emitting element 主 By combining two functional chips, it is possible to both simulate and adjust the sky color, and also solve the problem of large differences in light intensity.

[0058] The main light-emitting element 22 and the auxiliary light-emitting element 23 can be selected from Lambau light sources or CSP light sources according to the actual situation. The solar light-emitting element in the auxiliary light-emitting element 23 can be selected from the same or similar chip combination as the main light-emitting element.

[0059] In order to control the light intensity difference in the regions around the axis of symmetry inside the reflector after the light emitted by the polyhedral light source is reflected out, so that it is within the range that the human eye can distinguish, the angle of the main mounting surface of the polyhedral support and the light pattern of the main light-emitting component are further optimized.

[0060] Specifically as follows:

[0061] The angles between the two main mounting surfaces of the polyhedral support and the axis of symmetry of the parabolic inner reflector are both α. The light intensities of the two main light-emitting elements on the two main mounting surfaces in the direction normal to their own light-emitting surfaces are respectively I... 10 I 20 , and I 10 =I 20 See also Figure 6

[0062] The region near the axis of symmetry of the inner reflecting surface where the emitted rays from the two main light-emitting elements coincide is designated as the superposition region. The region between the normal direction of the main light-emitting element's own light-emitting surface and the superposition region is designated as the inner single-beam region. The region between the normal direction of the main light-emitting element's own light-emitting surface and the opening edge of the inner reflecting surface is designated as the outer single-beam region. To ensure that the light intensity difference between the regions on the inner reflecting surface does not exceed 15%, the following conditions must be met:

[0063] Light intensity I in the limited single-light region 1β and I 2β It satisfies the following relationship:

[0064] Formula 1: I 1β =I 10 *cos m β≥0.85I 10 I 2β =I 20 *cos m β≥0.85I 20 ; 1≤m≤30, β is the angle between the emitted ray from the main light source on this side in the external single light area and the normal direction of the light-emitting surface of the main light source on this side, and m is the maximum emission angle coefficient of the main light source; the maximum emission angle coefficient is related to the primary optics of the main light source. For the Lambert light source and the CSP light source, m is 1 when the maximum emission angle is 120°, 1.3~1.4 when it is 150°, and 2.3~2.4 when it is 175°.

[0065] The light intensity of the superposition region is I 叠加 It satisfies the following relationship:

[0066] I 叠加 =I1γ +I 2γ =I 10 *cos m γ+I 20 *cos m (180°-γ-2α); γ is the superposition region

[0067] The angle between the light emitted from one of the main light-emitting elements on one side and the normal direction of the light-emitting surface of the main light-emitting element on that side;

[0068] The light intensity of the inner reflecting surface located on the axis of symmetry satisfies the following relationship:

[0069] Formula 2: 0.85I 10 ≤I 叠加 =I 1γ +I 2γ =2*I 10 *cos m (90°-α)≤1.15I 10 ;

[0070] The angles between the emitted light rays from the superposition zone and the emitted light rays from the inner single-beam zone and the normal to the light-emitting surface of the main light-emitting element on that side satisfy the following relationship:

[0071] Formula 3: γ>90°-α.

[0072] The relationships obtained using the above formulas allow for faster design of polyhedral light sources to meet the design requirements of solar simulators. This is achieved by controlling the light intensity I on the inner reflecting surface of the emitted light rays from one of the main light-emitting elements, which pass through the axis of symmetry of the inner reflecting surface. 1γ Between 0.425 and 0.575I0, its light intensity I is similar to that of another main light-emitting element on the symmetrical surface of the prismatic polyhedron support. 2γ After stacking, the value reaches 0.85–1.15I. 10 Simultaneously, the minimum light intensity I of the emitted light from the control-side light source near the opening of the inner reflective surface is... 1β and I 2β Not less than 0.85I 10 This ensures that the light emitted by the main light source in the area, after being reflected by the reflector, has an intensity difference of no more than 15%, achieving an effect that the observer cannot distinguish the difference.

[0073] The following are the parameters for solar simulators using different types of main light-emitting elements:

[0074]

[0075]

[0076] Conclusion: By adopting a pyramidal or prism structure with at least two main mounting surfaces, and by optimizing the angle of the main mounting surfaces of the polyhedral support and the light pattern of the main light-emitting element, the light intensity difference reflected by the reflector is small and can be successfully controlled within 15%. Combined with the effect of simulating sunlight, the result is good.

[0077] Furthermore, the solar simulator structure of the present invention can be equipped with a beam-splitting collimator 3. The beam-splitting collimator 3 is directly covered at the end opening of the reflector 1 through a fitting or snap-fit ​​structure. The beam-splitting collimator 3 is a honeycomb structure composed of several columnar light guides arranged in a precise manner, and a reflective coating is provided on the inner wall of the beam-splitting collimator.

Claims

1. A sunlight simulator, characterized in that: include A reflector having a parabolic inner reflecting surface, the parabola of which has an axis of symmetry and a focus; A polyhedral light source includes a polyhedral support and a main light-emitting element. The polyhedral support has at least two main mounting surfaces for mounting the main light-emitting element. Both main mounting surfaces are located inside a reflector and near the focal point of a parabolic inner reflective surface. There is an angle between the main mounting surfaces and the axis of symmetry. The main light-emitting element for simulating sunlight is mounted on the main mounting surfaces, such that the main light emission direction of the main light-emitting element faces the inner reflective surface of the reflector while being neither parallel nor perpendicular to the axis of symmetry. The polyhedral support also includes a front mounting surface and an auxiliary light-emitting element disposed on the front mounting surface, wherein the main light emission direction of the auxiliary light-emitting element faces away from the inner reflective surface of the reflector. It includes a beam-splitting collimator that covers the end opening of the reflector, and the beam-splitting collimator is composed of a honeycomb structure formed by a series of precisely arranged columnar light guides.

2. The sunlight simulator according to claim 1, characterized in that: The auxiliary light-emitting element includes a blue light chip for simulating and supplementing the colors of the sky, with an emission wavelength range of 390-500nm.

3. The sunlight simulator according to claim 1, characterized in that: The auxiliary light-emitting element includes a solar light-emitting chip for simulating sunlight, and the luminous power W of the solar light-emitting chip is... 太 Less than the luminous power W of the main light-emitting element 主 .

4. The sunlight simulator according to claim 1, characterized in that: The auxiliary light-emitting element includes a blue light chip for simulating and supplementing the color of the sky and a solar light-emitting chip for simulating sunlight, wherein the luminous power W of the solar light-emitting chip is... 太 Less than the luminous power W of the main light-emitting element 主 .

5. The sunlight simulator according to claim 3 or 4, characterized in that: The luminous power of the solar-emitting chip and the luminous power of the main emitting element satisfy: 0 < W 太 ≤2d / D*W 主 D is the width of the parabolic opening of the reflective surface inside the reflector, and d is the width of the front prism surface in the direction of the parabolic opening width.

6. The sunlight simulator according to claim 1, characterized in that: The polyhedral support is a triangular prism structure with an isosceles triangle cross-section. The two prism surfaces where the legs of the isosceles triangle are located are the main mounting surfaces, and the prism surface where the base of the isosceles triangle is located is the front mounting surface perpendicular to the axis of symmetry.

7. The sunlight simulator according to claim 1, characterized in that: The polyhedral support is a regular square pyramid structure. The surface on which the side of the pyramid on the polyhedral support is located is the main mounting surface, and the surface on which the bottom of the pyramid on the polyhedral support is located is the front mounting surface perpendicular to the axis of symmetry.

8. The sunlight simulator according to claim 1, characterized in that: The polyhedral support includes a regular square pyramid structure located inside each reflector, an extension section of the reflector extending along the axis of symmetry, and a connecting section connecting the extension sections of each corresponding reflector. The surface on which the pyramidal side of the polyhedral support is located is the main mounting surface, and the surface at the outer end of the extension section is the front mounting surface.

9. The sunlight simulator according to claim 1, 2, 3, 4, 5, 7 or 8, characterized in that: The angles between the two main mounting surfaces of the polyhedral support and the axis of symmetry of the parabolic inner reflector are both α. The light intensities of the two main light-emitting elements on the two main mounting surfaces in the direction normal to their own light-emitting surfaces are respectively I... 10 I 20 , and I 10 =I 20 ; The region near the axis of symmetry of the inner reflector where the emitted rays from the two main light-emitting elements coincide is designated as the superposition region. The region between the normal direction of the main light-emitting element's own light-emitting surface and the superposition region is designated as the inner single-beam region. The region between the normal direction of the main light-emitting element's own light-emitting surface and the opening edge of the inner reflector is designated as the outer single-beam region. To ensure that the light intensity difference between the regions on the inner reflector does not exceed 15%, the following conditions must be met: Light intensity I in the limited single-light region 1β and I 2β It satisfies the following relationship: Formula 1: I 1β =I 10 *cos m β≥0.85I 10 I 2β =I 20 *cos m β≥0.85I 20 ; 1≤m≤30, β is the angle between the light emitted from one of the main light-emitting elements and the normal direction of the light-emitting surface of the main light-emitting element on that side, and m is the maximum light emission angle coefficient of the main light-emitting element; The light intensity of the superposition region is I 叠加 It satisfies the following relationship: I 叠加 =I 1γ +I 2γ =I 10 *cos m γ+I 20 *cos m (180°-γ-2α); γ is the angle between the light emitted from one of the main light-emitting elements and the normal direction of the light-emitting surface of that main light-emitting element; The light intensity of the inner reflecting surface located on the axis of symmetry satisfies the following relationship: Formula 2: 0.85I 10 ≤I 叠加 =I 1γ +I 2γ =2*I 10 *cos m (90°-α)≤1.15I 10 ; The angles between the emitted light rays from the superposition zone and the emitted light rays from the inner single-beam zone and the normal to the light-emitting surface of the main light-emitting element on that side satisfy the following relationship: Formula 3: γ>90°-α.

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