A multifunctional natural light homogenizing lighting device

Abstract

This invention proposes a multifunctional natural light homogenizing lighting device. The designed device can evenly distribute natural light entering through windows during the day to every corner of the room, making full use of natural light for indoor lighting. Simultaneously, it filters out infrared rays and heat radiation from natural light, blocking heat conduction and maintaining a stable indoor temperature. Alternatively, it can filter out long-wave ultraviolet and medium-wave ultraviolet rays from natural light, preventing or mitigating skin damage and aging of indoor furnishings caused by ultraviolet radiation. By using natural light for illumination, the energy used for lighting is reduced. Alternatively, it can utilize a photochromic coating to regulate solar radiation entering the room, ensuring a stable indoor lighting environment, or a thermochromic coating to regulate solar radiation entering the room, also ensuring a stable indoor lighting environment. Furthermore, it effectively protects indoor privacy. The device is lightweight, thin, easy to mass-produce, environmentally friendly, and pollution-free, and can be used as lighting curtains, indoor blinds, and window glass.

Description

Technical Field

[0001] This invention belongs to the field of lighting system design and beam shaping technology, and particularly relates to a multifunctional natural light homogenization lighting device. The designed composite natural light homogenization lighting device can evenly distribute natural light entering through windows during the day to every corner of the room, making full use of natural light for indoor lighting. Simultaneously, it filters out infrared rays and heat radiation from natural light, blocking temperature conduction and maintaining a stable indoor temperature. Alternatively, it can filter out long-wave ultraviolet radiation (UVA) and medium-wave ultraviolet radiation (UVB) from natural light, preventing or mitigating skin damage and aging of indoor furnishings caused by ultraviolet radiation. By using natural light, the energy used for lighting is reduced. Alternatively, it can utilize a photochromic coating to regulate the solar radiation entering the room, ensuring a stable indoor lighting environment, or a thermochromic coating to regulate the solar radiation entering the room, ensuring a stable indoor lighting environment. This results in energy saving, emission reduction, and improved energy utilization efficiency. Furthermore, it effectively protects indoor privacy. The device is lightweight, thin, easy to mass-produce, environmentally friendly, and pollution-free, and can be used as lighting curtains, indoor blinds, and window glass. Background Technology

[0002] 97% of the solar radiation energy in natural light is concentrated in the wavelength range of 0.3-2.5μm, and this part of the energy comes from outdoors; the radiation energy of objects below 100℃ is concentrated in the long-wavelength band above 2.5μm, and this part of the energy mainly comes from indoors. Therefore, in addition to improving lighting efficiency, it is essential to carry out energy-saving building design, develop and use thermal insulation building materials, especially to develop and use new functional lighting devices that are both light-transmitting and transparent, as well as having directional heat transfer or insulation properties, and to use energy-saving, safe and environmentally friendly solar daylighting devices without changing the original building structure.

[0003] Natural light has a wide wavelength range, among which ultraviolet (UV) radiation falls within the 200-400 nm range. Due to its short wavelength and high energy, UV radiation is highly harmful to life and various plants on Earth. It can burn human skin, oxidize wood causing fading, and damage, age, or degrade polymers and organic materials. UV radiation can be divided into three different bands based on wavelength: long-wave ultraviolet radiation (UVA) with a wavelength range of 320-400 nm, medium-wave ultraviolet radiation (UVB) with a wavelength range of 280-320 nm, and short-wave ultraviolet radiation (UVC) with a wavelength range of 100-280 nm. UVA has the strongest penetrating power, capable of penetrating most transparent glass and plastic products. Approximately 98% of UVA in sunlight can penetrate clouds and the ozone layer to reach the ground directly. UVA primarily affects the entire epidermis and dermis, inducing damage to mitochondrial DNA in mammals, leading to mutations. It can also have long-term effects on biological connective tissues, causing severe photoaging damage to the skin, such as wrinkles, sagging, pigmentation, uneven skin tone, dryness, and aging. In severe cases, it may even lead to cell carcinogenesis. UVA is also a significant factor in the aging of polymer materials. After prolonged exposure, a series of photochemical reactions occur within polymer materials, resulting in brittleness, discoloration, reduced transparency and mechanical properties, and a significantly shortened lifespan. UVB has lower penetrating power and is almost completely absorbed by the ozone layer and transparent glass and plastic products. Under direct sunlight, only about 2% of UVB reaches the Earth's surface. Long-term exposure to ultraviolet radiation can cause skin darkening and even redness and swelling. It can also inhibit plant pollination and growth, destroy chlorophyll in chloroplasts, and hinder physiological processes such as photosynthesis. UVC is the most damaging to living organisms, but it has the worst penetrating power, almost never reaching the ground. Therefore, ultraviolet protection mainly targets light in the 320-400nm wavelength range. In addition to utilizing natural light to improve lighting efficiency, special designs are needed to address ultraviolet shielding in order to provide a more comfortable and healthy living environment. It is essential to use energy-saving, safe, and environmentally friendly solar lighting devices without altering the original building structure.

[0004] In addition to improving lighting efficiency, it is essential to implement energy-saving building design that allows buildings to autonomously adjust their spectral characteristics to adapt to changes in external conditions, thereby regulating the indoor environment and achieving high energy efficiency. Utilizing the properties of photochromic materials, the color of the lighting device gradually deepens when light intensity increases, altering the transmittance and reflectance of sunlight. This, in turn, regulates the light intensity and heat radiation entering the room through windows. When light intensity decreases, the transmittance of the lighting device increases, resulting in more light and heat entering the room. This achieves the goal of regulating the indoor environment and saving energy without altering the original building structure, integrating the advantages of energy saving, dimming, and decoration.

[0005] Thermochromic coatings can reduce the heating and cooling loads of buildings and mitigate the urban heat island effect. Their optical properties, such as spectral reflectance, transmittance, and absorptivity, are related to their surface temperature. By selecting suitable materials and ensuring the color-changing temperature is within an appropriate range, the thermochromic coating will be light-colored at higher temperatures to maximize sunlight reflection, and dark-colored at lower temperatures to absorb more sunlight. In hot summers, indoor temperatures can be relatively lower, and in cold winters, relatively higher, achieving intelligent interaction between the building and its environment. This reduces the building's heating and cooling loads and achieves the goals of regulating the indoor environment and saving energy without altering the original building structure, integrating the advantages of energy saving, light control, and decoration. Summary of the Invention

[0006] The purpose of this invention is to address the problems in existing technologies by proposing a multifunctional natural light homogenization lighting device. This device can evenly distribute natural light entering through windows during the day to all corners of the room, fully utilizing natural light for indoor lighting. Simultaneously, it reflects infrared and thermal radiation, providing heat insulation, or absorbs and reflects ultraviolet rays, which is beneficial to human health. Alternatively, it can utilize a photochromic coating to regulate the solar radiation entering the room, or a thermochromic coating to regulate the solar radiation entering the room, ensuring a stable indoor lighting environment, saving energy, reducing emissions, and improving energy utilization efficiency.

[0007] This invention is achieved through the following technical solution: This invention proposes a multifunctional natural light homogenizing lighting device, comprising a first homogenizing substrate 1, a second homogenizing substrate 3, and a multifunctional layer 2 sandwiched between them. The first homogenizing substrate 1, which is in direct contact with the outdoors, is a single-plane, freeform surface array, or lens array; the second homogenizing substrate 3, which is in direct contact with the indoor environment, is a freeform surface array, lens array, or sawtooth grating array. The first homogenizing substrate 1 is used to collect outdoor high-angle natural light, which is then processed by the multifunctional layer 2 and transmitted to the second homogenizing substrate 3. The second homogenizing substrate 3 is used to deflect the incident natural light into the indoor space after refraction through an inclined surface.

[0008] The array of freeform surfaces can be either convex or concave. The convex freeform surface refracts light in the horizontal direction. The expression for the thickness d1 at different positions (x1, y1) on the convex freeform surface is: Where n is the refractive index, r1 is the radius of curvature at the vertex of the convex freeform surface, θ1 is the surface tilt angle of the convex freeform surface, and light propagates horizontally through refraction. The radius of curvature is 1-5 times the minimum distance between the working surfaces of the two uniform light substrates. The expression for the thickness d2 at different positions (x2, y2) on the concave freeform surface is: Where n is the refractive index, r2 is the radius of curvature of the vertex of the concave freeform surface, θ2 is the surface tilt angle of the concave freeform surface, and the light propagates in the horizontal direction through refraction. The radius of curvature is 1-5 times the minimum distance between the working surfaces of the two uniform light substrates.

[0009] The lens array uses either convex or concave lenses. The expression for the thickness z1 at different positions (x1, y1) on the convex lens is: r3 is the radius of the curved surface, which is 1-5 times the minimum distance between the working surfaces of the two uniform light substrates; the expression for the thickness z2 at different positions (x2, y2) on the concave lens is: r4 is the surface radius, which is 1-5 times the minimum distance between the working surfaces of the two uniform light substrates;

[0010] The expression for the thickness t at different positions (x, y) on a single structural unit of the sawtooth grating array is as follows: θ3 is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, and its value ranges from 20° to 70°.

[0011] Furthermore, for natural light homogenizing substrates with different surface shapes, the freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent focal length of the lens in the freeform surface array, λ is the center wavelength of the natural light, and α1 is the incident angle of the natural light on the freeform surface; the lens array adds phase modulation to the incident light. It can be represented as (x2, y2) represents the position of the incident wavefront of the lens array, λ is the center wavelength of natural light, and f2 is the focal length of the lens; the sawtooth grating array adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y3 is the position of the incident wavefront of the sawtooth surface array, and α3 is the incident angle of natural light on the sawtooth surface.

[0012] Furthermore, the multifunctional layer 2 is a thermal infrared reflective layer. The first uniform light substrate 1 is used to collect outdoor high-angle natural light, and the infrared light and thermal radiation are filtered by the thermal infrared reflective layer before being conducted to the second uniform light substrate 3.

[0013] The infrared heat reflective layer is a metal film or a doped semiconductor film. While maintaining high visible light transmittance, the infrared heat reflective layer blocks the transmission of infrared light, reducing heat exchange on both sides of the uniform light substrate. During the day when temperatures are high, it reduces the transmission of solar energy through windows into the room, ensuring that the indoor temperature remains low even under strong sunlight, significantly reducing the burden on air conditioning. When temperatures are low, it blocks indoor heat from being conducted to the outside through windows and reflects far-infrared radiation from the room, thereby reducing the energy consumption of indoor heating equipment.

[0014] Furthermore, outdoor natural light is collected by the working plane of the first uniform light substrate 1 and transmitted to the thermal infrared reflective layer through the intermediate medium;

[0015] When the outdoor temperature is higher than the indoor temperature, the thermal infrared reflective layer reflects and blocks most of the solar heat and infrared rays, achieving a heat insulation effect; when the outdoor temperature is lower than the indoor temperature, the thermal infrared reflective layer has poor thermal conductivity, blocking the conduction of heat and maintaining a stable indoor temperature.

[0016] The light filtered by the thermal infrared reflective layer is deflected into the indoor space after passing through the second uniform light substrate 3, achieving uniform illumination of the incident light, making the indoor light soft and comfortable, avoiding glare, and creating a comfortable indoor environment.

[0017] Furthermore, the multifunctional layer 2 is an ultraviolet shielding film layer. The first light-monopolizing substrate 1 is used to collect outdoor high-angle natural light and filter most of the ultraviolet rays in the UVA (320-400nm) and UVB (280-320nm) bands through the ultraviolet shielding film layer, and then conducts them to the second light-monopolizing substrate 3.

[0018] The ultraviolet shielding film is either an inorganic or organic ultraviolet shielding film, which can absorb or reflect ultraviolet rays of different wavelengths in sunlight, thereby effectively blocking ultraviolet rays from entering the room and preventing harm to human health and indoor furnishings caused by ultraviolet radiation.

[0019] Furthermore, outdoor natural light is collected by the working plane of the first uniform light substrate 1 and transmitted to the ultraviolet shielding film layer through an intermediate medium;

[0020] The ultraviolet shielding film reflects and blocks most of the ultraviolet rays;

[0021] The light filtered by the ultraviolet shielding film is deflected into the indoor space after passing through the second uniform light substrate 3, achieving uniform illumination of the incident light, making the indoor light soft and comfortable, avoiding glare, and creating a comfortable indoor environment.

[0022] Furthermore, the multifunctional layer 2 is a photochromic coating. The first uniform light substrate 1 is used to collect outdoor high-angle natural light, and the transmittance of the lighting device is adjusted by the photochromic coating before being conducted to the second uniform light substrate 3.

[0023] The photochromic coating is either an inorganic or organic photochromic coating. When exposed to strong ultraviolet light or sunlight, the photochromic coating absorbs light in the visible spectrum and automatically changes color. After the intense light exposure stops, it reversibly and automatically returns to its initial transparent state. For different climate zones, the photochromic coating has different abilities to reduce the burden of cold and heat. In terms of material selection, high adaptability to the light environment can be achieved based on the design of the color-changing point and the reflectivity threshold range.

[0024] Furthermore, outdoor natural light is collected by the working plane of the first uniform light substrate 1 and transmitted to the photochromic coating through an intermediate medium;

[0025] When outdoor natural light is strong, the photochromic coating reflects and blocks most of the natural light; when outdoor natural light becomes weak, the photochromic coating restores high transmittance, maintaining stable indoor lighting conditions.

[0026] The light filtered by the photochromic coating is deflected into the indoor space after passing through the second uniform light substrate 3, achieving uniform illumination of the incident light, making the indoor light soft and comfortable, avoiding glare, and creating a comfortable indoor environment.

[0027] Furthermore, the multifunctional layer 2 is a thermochromic coating. The first uniform light substrate 1 is used to collect outdoor high-angle natural light, and the reflectivity, transmittance and absorptivity of the lighting device are dynamically adjusted by the thermochromic coating, and then conducted to the second uniform light substrate 3.

[0028] The thermochromic coating is an inorganic reversible thermochromic coating or an organic reversible thermochromic coating. The thermochromic coating can intelligently adjust the color of the film layer according to different temperatures, thereby achieving different transmittance and reflectance. For different climate zones, the thermochromic coating has different abilities to reduce the cold and heat burden. In terms of material selection, high adaptability to climate environment can be achieved according to the design of the temperature change point and the reflectance threshold range.

[0029] Furthermore, outdoor natural light is collected by the working plane of the first uniform light substrate 1 and transmitted to the thermochromic coating through an intermediate medium. Its optical properties, such as spectral reflectivity, transmittance and absorptivity, are related to its surface temperature. As the surface temperature changes, the material exhibits different colors and its reflection and absorption of solar radiation also vary.

[0030] At higher temperatures, the thermochromic coating appears light-colored, reflecting and blocking most of the solar heat and infrared rays, thus achieving a heat insulation effect; at lower temperatures, the thermochromic coating appears dark-colored, absorbing more solar radiation and reducing energy consumption for indoor insulation.

[0031] The light filtered by the thermochromic coating is deflected into the indoor space after passing through the second uniform light substrate 3, achieving uniform illumination of the incident light, making the indoor light soft and comfortable, avoiding glare, and creating a comfortable indoor environment. Attached Figure Description

[0032] Figure 1 This is a schematic diagram of the structure of a single-piece heat-insulating natural light homogenizing lighting device based on a combination of a single plane and a convex freeform surface, as provided in Embodiment 1 of the present invention.

[0033] Figure 2 This is a schematic diagram of the structure of a single-piece heat-insulating natural light homogenizing lighting device based on a combination of a single plane and a convex lens, provided in Embodiment 1 of the present invention.

[0034] Figure 3 This is a schematic diagram of the structure of a single-piece heat-insulating natural light homogenizing lighting device based on a combination of a single plane and a sawtooth grating, provided in Embodiment 1 of the present invention.

[0035] Figure 4 This is a schematic diagram of the structure of a single-piece heat-insulating natural light homogenizing lighting device based on a combination of a convex lens and a convex freeform surface, as provided in Embodiment 1 of the present invention.

[0036] Figure 5 This is a schematic diagram of the structure of a single-piece heat-insulating natural light homogenizing lighting device based on a combination of convex lenses, provided in Embodiment 1 of the present invention.

[0037] Figure 6 This is a schematic diagram of the structure of a monolithic heat-insulating natural light homogenizing lighting device based on a combination of a convex lens and a sawtooth grating, provided in Embodiment 1 of the present invention.

[0038] Figure 7 This is a schematic diagram of the structure of a single-piece heat-insulating natural light homogenizing lighting device based on the combination of two convex free-form surfaces provided in Embodiment 1 of the present invention.

[0039] Figure 8This is a schematic diagram of the structure of a single-piece heat-insulating natural light homogenizing lighting device based on a combination of a convex freeform surface and a convex lens, as provided in Embodiment 1 of the present invention.

[0040] Figure 9 This is a schematic diagram of the structure of a monolithic heat-insulating natural light homogenizing lighting device based on a combination of a convex freeform surface and a sawtooth grating, as provided in Embodiment 1 of the present invention.

[0041] Figure 10 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of a single plane and a convex freeform surface, provided in Embodiment 2 of the present invention.

[0042] Figure 11 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of a single plane and a convex lens, provided in Embodiment 2 of the present invention.

[0043] Figure 12 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of a single plane and a sawtooth grating, provided in Embodiment 2 of the present invention.

[0044] Figure 13 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of a convex lens and a convex freeform surface, provided in Embodiment 2 of the present invention.

[0045] Figure 14 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of convex lenses, provided in Embodiment 2 of the present invention.

[0046] Figure 15 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of a convex lens and a sawtooth grating, provided in Embodiment 2 of the present invention.

[0047] Figure 16 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of two convex freeform surfaces, as provided in Embodiment 2 of the present invention.

[0048] Figure 17 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of a convex freeform surface and a convex lens, as provided in Embodiment 2 of the present invention.

[0049] Figure 18 This is a schematic diagram of the structure of a monolithic ultraviolet shielding natural light homogenizing illumination device based on a combination of a convex freeform surface and a sawtooth grating, provided in Embodiment 2 of the present invention.

[0050] Figure 19This is a schematic diagram of the structure of a single-piece photosensitive color-changing natural light homogenizing illumination device based on a combination of a single plane and a convex freeform surface, provided in Embodiment 3 of the present invention.

[0051] Figure 20 This is a schematic diagram of the structure of a single-piece photosensitive color-changing natural light homogenizing illumination device based on a combination of a single plane and a convex lens, provided in Embodiment 3 of the present invention.

[0052] Figure 21 This is a schematic diagram of the structure of a single-piece photosensitive color-changing natural light homogenizing illumination device based on a combination of a single plane and a sawtooth grating, provided in Embodiment 3 of the present invention.

[0053] Figure 22 This is a schematic diagram of the structure of a single-piece photosensitive color-changing natural light homogenizing illumination device based on a combination of a convex lens and a convex freeform surface, provided in Embodiment 3 of the present invention.

[0054] Figure 23 This is a schematic diagram of the structure of a single-piece photosensitive color-changing natural light homogenizing illumination device based on a combination of convex lenses, provided in Embodiment 3 of the present invention.

[0055] Figure 24 This is a schematic diagram of the structure of a single-piece photosensitive color-changing natural light homogenizing illumination device based on a combination of a convex lens and a sawtooth grating, provided in Embodiment 3 of the present invention.

[0056] Figure 25 This is a schematic diagram of the structure of a single-piece photosensitive color-changing natural light homogenizing illumination device based on a combination of two convex freeform surfaces, as provided in Embodiment 3 of the present invention.

[0057] Figure 26 This is a schematic diagram of the structure of a single-piece photosensitive color-changing natural light homogenizing illumination device based on a combination of a convex freeform surface and a convex lens, provided in Embodiment 3 of the present invention.

[0058] Figure 27 This is a schematic diagram of the structure of a monolithic photosensitive color-changing natural light homogenizing illumination device based on a combination of a convex freeform surface and a sawtooth grating, provided in Embodiment 3 of the present invention.

[0059] Figure 28 This is a schematic diagram of the structure of a single-piece thermochromic natural light homogenizing illumination device based on a combination of a single plane and a convex freeform surface, provided in Embodiment 4 of the present invention.

[0060] Figure 29 This is a schematic diagram of the structure of a single-piece thermochromic natural light homogenizing illumination device based on a combination of a single plane and a convex lens, provided in Embodiment 4 of the present invention.

[0061] Figure 30 This is a schematic diagram of the structure of a monolithic thermochromic natural light homogenizing illumination device based on a combination of a single plane and a sawtooth grating, provided in Embodiment 4 of the present invention.

[0062] Figure 31 This is a schematic diagram of the structure of a single-piece thermochromic natural light homogenizing illumination device based on a combination of a convex lens and a convex freeform surface, provided in Embodiment 4 of the present invention.

[0063] Figure 32 This is a schematic diagram of the structure of a single-piece thermochromic natural light homogenizing illumination device based on a combination of convex lenses, provided in Embodiment 4 of the present invention.

[0064] Figure 33 This is a schematic diagram of the structure of a monolithic thermochromic natural light homogenizing illumination device based on a combination of a convex lens and a sawtooth grating, provided in Embodiment 4 of the present invention.

[0065] Figure 34 This is a schematic diagram of the structure of a single-piece thermochromic natural light homogenizing illumination device based on a combination of two convex freeform surfaces, as provided in Embodiment 4 of the present invention.

[0066] Figure 35 This is a schematic diagram of the structure of a single-piece thermochromic natural light homogenizing illumination device based on a combination of a convex freeform surface and a convex lens, provided in Embodiment 4 of the present invention.

[0067] Figure 36 This is a schematic diagram of the structure of a monolithic thermochromic natural light homogenizing illumination device based on a combination of a convex freeform surface and a sawtooth grating, provided in Embodiment 4 of the present invention.

[0068] In the figure, 1 is the first homogenizing substrate, 2 is the multifunctional layer, and 3 is the second homogenizing substrate. Detailed Implementation

[0069] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0070] Example 1

[0071] For the infrared heat reflective layer, the metal film layer is a film system composed of multiple metals or other compounds. The metals used include, but are not limited to, silver, aluminum, and copper. Macroscopically, it is a thin film with a thickness of less than 0.1 mm. Microscopically, it is divided into one, two, or three metal heat insulation films.

[0072] For the infrared heat reflective layer, the doped semiconductor film mainly consists of metals and transition metal oxides, including but not limited to: In2O3-based (ITO tin-doped indium oxide), SnO2-based (FTO fluorine-doped tin oxide, ATO aluminum-doped tin oxide) and ZnO2-based (AZO aluminum-doped zinc oxide). Macroscopically, it appears as a thin film with a thickness of less than 0.1 mm, and microscopically, it is a multilayer metal-doped oxide heat insulation film.

[0073] Methods for preparing infrared heat reflective layers include, but are not limited to, sol-gel method, vacuum evaporation method, chemical vapor deposition method, vacuum magnetron sputtering method, and spray pyrolysis method.

[0074] For natural light homogenizing substrates of different surface shapes, the working plane of the first homogenizing substrate always faces the incident direction of natural light, and the normal of the working plane forms an acute angle with the incident natural light. The device material for natural light homogenizing substrates of different surface shapes is a transparent material with a transmittance of 85% or higher in the visible light band, including but not limited to glass, resin, and transparent plastics. For natural light homogenizing substrates of different surface shapes, except for the case where the first homogenizing substrate is a single plane, the array of working planes of the two homogenizing substrates is a square full-aperture array with a fill rate of 95% or higher, and the surface shapes of the two substrates correspond one-to-one, with the center position of the surface shape matching the optical axis.

[0075] As attached Figure 1 As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a combination of a single-plane and a convex freeform surface. It includes two array-shaped light-homogenizing substrates. The first substrate has a single-plane working surface, and the second substrate has a convex freeform surface array. The single-plane collects outdoor natural light, filters infrared radiation and thermal radiation through an infrared reflective layer, and the filtered light is then conducted to the convex freeform surface array via an intermediate medium. The convex freeform surface array deflects the incident natural light through its inclined surfaces into the indoor space. Each convex freeform surface array comprises n unit structures, where n is a natural number greater than or equal to 1.

[0076] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the individual unit structure of the convex free-surface array is a convex free-form surface, and the thickness d1 at different positions (x, y) on the convex free-form surface is expressed as follows: r is the radius of curvature of the surface, θ is the tilt angle, and the surface shape can be spherical or other shapes. The radius of curvature is 1-5 times the minimum distance between the plane and the convex freeform surface. The convex freeform surface array adds phase modulation to the incident light. It can be represented as (x,y) represents the position of the incident wavefront of the freeform surface array, f is the focal length of the equivalent lens in the freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident light angle.

[0077] More specifically: the convex freeform surface array is a square full-aperture array with a fill rate of over 95%.

[0078] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0079] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the convex freeform surface has a radius r = -1mm, a surface tilt angle θ = 45°, a spacing of 1.5mm between the two uniform light substrate working surfaces, an array size of 1mm*1mm, a 5*5 array, and ZF6 glass as the material.

[0080] As attached Figure 2 As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a combination of a single plane and convex lenses. It includes two homogenizing substrates arranged in a front and rear array. The first homogenizing substrate has a single plane as its working surface, and the second homogenizing substrate has a convex lens array as its working surface. The single plane collects outdoor natural light, filters infrared radiation and thermal radiation through an infrared reflective layer, and the filtered light is then conducted to the convex lens array through an intermediate medium. The convex lens array deflects the incident natural light into the indoor space after refraction through an inclined surface. Each convex lens array includes n unit structures, where n is a natural number greater than or equal to 1.

[0081] More specifically: the two arrayed surfaces respectively modulate different phases of the incident light. Specifically, the individual unit structure of the convex lens array is a convex lens, and the expression for the thickness d2 at different positions (x, y) on the convex lens is: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the plane and the convex lens. The convex lens array adds phase modulation to the incident light. It can be represented as (x,y) represents the position of the incident wavefront of the lens array, f is the focal length of the lens, and λ is the center wavelength of natural light.

[0082] More specifically: the convex lens array is a square full-aperture array with a fill rate of over 95%.

[0083] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0084] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the focal length of the convex lens is f = 5mm, the interval between the two uniform light substrate working surfaces is 1.5mm, the array size is 1mm*1mm, a 5*5 array is selected, and ZF6 glass is selected as the material.

[0085] As attached Figure 3As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a combination of a single-plane and a sawtooth grating. It includes two homogenizing substrates arranged in a front and rear array. The first homogenizing substrate has a single-plane working surface, and the second homogenizing substrate has a sawtooth surface array. The single-plane substrate collects outdoor natural light, filters infrared radiation and thermal radiation through an infrared reflective layer, and the filtered light is then conducted to the sawtooth surface array via an intermediate medium. The sawtooth surface array deflects the incident natural light into the indoor space after refraction through the inclined surface. Each sawtooth surface array includes n unit structures, where n is a natural number greater than or equal to 1.

[0086] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the thickness d3 at different positions (x, y) on a single structural unit of the sawtooth surface array is expressed as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating. The sawtooth surface array adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y is the position of the incident wavefront of the sawtooth surface array, and θ1 is the incident light angle.

[0087] More specifically: the serrated surface array is a square full-aperture array with a fill rate of over 95%.

[0088] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0089] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the tilt angle of the sawtooth surface array grating is θ = 45°, the interval between the two planes is 1.5mm, the array size is 1mm*1mm, a 5*5 array is selected, and ZF6 glass is selected as the material to simulate the light divergence effect.

[0090] As attached Figure 4 As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a combination of convex lenses and convex freeform surfaces. It includes two homogenizing substrates arranged in a front and rear array. The working surface of the first homogenizing substrate is a convex lens array, and the working surface of the second homogenizing substrate is a convex freeform surface array. The convex lens array collects outdoor natural light, filters infrared radiation and thermal radiation through an infrared reflective layer, and the filtered light is transmitted to the convex freeform surface array through an intermediate medium. The convex freeform surface array deflects the incident natural light into the indoor space after refraction through an inclined surface. Both the convex lens array and the convex freeform surface array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0091] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the convex lens array surface of the first homogenizing substrate adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the lens array, λ is the incident wavelength (usually the center wavelength), and f is the focal length of the lens. The convex freeform surface array of the second homogenizing substrate adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the freeform surface array, f2 is the equivalent focal length of the convex freeform surface, and θ1 is the incident light angle.

[0092] More specifically: the lens surface of the convex lens faces the direction of natural light incident, and the normal of the lens surface forms an acute angle with the angle of the incident natural light. Natural light incident from a high angle outside can be dispersed in parallel to all corners of the room after passing through the designed device.

[0093] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the lens array and the freeform surface array. The convex freeform surface array refracts most of the light rays in the horizontal direction through refraction. The expression for the thickness d1 at different positions (x2, y2) on the convex freeform surface is: Where n is the refractive index, r is the radius of curvature of the vertex, and θ2 is the surface tilt angle, which allows light to propagate horizontally through refraction.

[0094] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0095] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0096] More specifically: To verify the effectiveness of the device described above, the convex lens array uses spherical lenses with a radius of curvature r = 1 mm and a focal length f = 2 mm; the convex freeform surface has a radius of curvature r = -1 mm and a surface tilt angle θ2 = 45°. The interval between the convex lens array and the convex freeform surface array is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is used, and ZF6 glass is selected as the material.

[0097] As attached Figure 5As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a combination of two convex lenses. It includes two homogenizing substrates arranged in a front and rear array. The working surfaces of both the first and second homogenizing substrates are convex lens arrays. The first convex lens array collects outdoor natural light, filters infrared radiation and thermal radiation through an infrared reflective layer, and then transmits the filtered light through an intermediate medium to the second convex lens array. The second convex lens array deflects the incident natural light into the indoor space after refraction through an inclined surface. Both convex lens arrays include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0098] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the convex lens array surface adds phase modulation to the incident light. It can be represented as (x1,y1) represents the position of the incident wavefront of the lens array, λ represents the incident wavelength (usually the center wavelength), and f represents the focal length of the lens.

[0099] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The focal length of the second convex lens array is 2-5 times that of the first convex lens array. The second convex lens refracts most of the light rays in the horizontal direction.

[0100] More specifically: a convex lens facing the direction of natural light, with the normal of the lens surface forming an acute angle with the angle of the incident natural light, allows natural light incident from a high angle outdoors to be diffused in parallel to all corners of the room through the designed device. Specifically, the rear focal point of a single unit lens in the first convex lens array coincides with the front focal point of a single unit lens in the second convex lens array, forming a Keplerian telescope structure that diffuses light into the indoor space.

[0101] More specifically, the unit sizes of the second convex lens array and the first convex lens array are not equal. The size of a single unit lens in the second convex lens array is such that it can collect and converge all the beams of the corresponding unit of the first positive lens array.

[0102] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0103] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex lens is selected as a unit lens with a focal length of 2mm, the second convex lens is selected as a unit lens with a focal length of 5mm, and the distance between the first convex lens and the second convex lens is 7mm.

[0104] As attached Figure 6As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a combination of convex lenses and sawtooth gratings. It includes two homogenizing substrates arranged in a front and rear array. The working surface of the first homogenizing substrate is a convex lens array, and the working surface of the second homogenizing substrate is a sawtooth grating array. The convex lens array collects outdoor natural light, filters infrared radiation and thermal radiation through an infrared reflective layer, and the filtered light is then conducted through an intermediate medium to the convex freeform surface array. The sawtooth grating array deflects the incident natural light through an inclined surface into the indoor space. Both the convex lens array and the sawtooth grating array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0105] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the convex lens array surface of the first homogenizing substrate adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the lens array, λ is the incident wavelength (usually the center wavelength), and f is the focal length of the lens. The sawtooth grating array surface of the second homogenizing substrate adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y2 is the position of the incident wavefront of the sawtooth surface array, and θ1 is the incident light angle.

[0106] More specifically: the lens surface of the convex lens faces the direction of natural light incident, and the normal of the lens surface forms an acute angle with the angle of the incident natural light. Natural light incident from a high angle outside can be dispersed in parallel to all corners of the room after passing through the designed device.

[0107] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum spacing between the lens array and the sawtooth grating array. The expression for the thickness d at different positions (x2, y2) on a single structural unit of the sawtooth surface array is as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, which causes light to propagate horizontally through refraction.

[0108] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0109] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0110] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the convex lens array is selected from spherical lenses with a radius of curvature of r = 1 mm and a focal length of f = 2 mm; the sawtooth grating tilt angle θ = 45°, the lens array and the sawtooth grating are in one-to-one correspondence, the interval between the two planes is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and the material is ZF6 glass.

[0111] As attached Figure 7 As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a combination of freeform convex and convex surfaces. It includes two uniform light substrates arranged in front and behind arrays. Both the working surfaces of the first and second uniform light substrates are convex freeform surfaces. Outdoor high-angle natural light is collected by the first convex freeform surface array, filtered by an infrared reflective layer to remove infrared radiation and thermal radiation, and then transmitted through an intermediate medium to the convex freeform surface array. The second convex freeform surface array deflects the incident natural light through its inclined surface into the indoor space. Both the first and second convex freeform surface arrays include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0112] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second convex freeform surface array adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the freeform surface array, f2 represents the equivalent lens focal length in the second convex freeform surface array, λ represents the center wavelength of natural light, and θ2 represents the incident angle of the incident light on the first convex freeform surface.

[0113] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other shapes. The radius of curvature is 1-5 times the minimum spacing between the two convex freeform surface arrays. The expression for the thickness d2 at different positions (x2, y2) on the second convex freeform surface is as follows: r2 is the radius of the surface, α2 is the inclination angle of the second convex freeform surface, and the surface form can be a sphere, a parabola, or other forms. The radius of the surface is 1-5 times the minimum spacing between the two convex freeform surface arrays.

[0114] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0115] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0116] More specifically: To verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm and a surface tilt angle of α1 = 10°, the second convex freeform surface array has a radius of curvature of r2 = -1 mm and a surface tilt angle of α2 = 35°, the first convex freeform surface lens array and the second convex freeform surface lens array correspond one-to-one, the interval between the two planes is 1.2 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and ZF6 glass is selected as the material.

[0117] As attached Figure 8 As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a convex freeform surface and a convex lens array. It includes two homogenizing substrates arranged in a front and rear array configuration. The working surface of the first homogenizing substrate is a convex freeform surface, and the working surface of the second homogenizing substrate is a convex lens. Outdoor high-angle natural light is collected by the convex freeform surface array, filtered for infrared radiation and thermal radiation by an infrared reflective layer, and then transmitted through an intermediate medium to the convex lens array. The convex lens array is used to deflect the incident natural light into the indoor space after refraction through the inclined surface. Both the convex freeform surface array and the convex lens array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0118] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second convex lens array surface adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the lens array, λ represents the center wavelength of the incident natural light, and f2 represents the focal length of the lens.

[0119] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other shapes. The radius of curvature is 1-5 times the minimum distance between the lens array and the freeform surface array. The expression for the thickness d2 at different positions (x2, y2) on the second convex lens is as follows:

[0120] r2 is the radius of the surface. The surface shape can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the lens array and the freeform surface array.

[0121] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0122] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0123] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm and a surface tilt angle of α1 = 10°. The second convex lens array has a focal length of f = 5 mm. The first convex freeform surface array and the second convex lens array correspond one-to-one. The interval between the two planes is 1.5 mm. The array size is 1 mm * 1 mm. A 5 * 5 array is selected. ZF6 glass is selected as the material.

[0124] As attached Figure 9 As shown, this embodiment provides a composite heat-insulating natural light homogenizing lighting device based on a convex freeform surface and a sawtooth grating array. It includes two homogenizing substrates in the form of arrays, one at the front and one at the back. The working surface of the first homogenizing substrate is a convex freeform surface, and the working surface of the second homogenizing substrate is a sawtooth grating surface. Outdoor high-angle natural light is collected by the convex freeform surface array, filtered by an infrared reflective layer to remove infrared radiation and thermal radiation, and then transmitted through an intermediate medium to the sawtooth grating array. The sawtooth grating array is used to deflect the incident natural light into the indoor space after refraction through the inclined surface. Both the convex freeform surface array and the sawtooth grating array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0125] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second sawtooth grating array surface adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y2 is the position of the incident wavefront of the sawtooth surface array, and θ2 is the incident light angle.

[0126] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other forms. The radius of curvature is 1-5 times the minimum distance between the lens array and the freeform surface array. The expression for the thickness d at different positions (x2, y2) on a single structural unit of the sawtooth surface array is as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, which causes light to propagate horizontally through refraction.

[0127] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0128] More specifically: the infrared heat reflective layer is a single-layer metallic silver film, which macroscopically appears as a film with a thickness of less than 0.1 mm.

[0129] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm, a surface tilt angle of α1 = 10°, a sawtooth grating surface tilt angle of θ = 35°, the convex freeform surface array and the sawtooth grating array correspond one-to-one, the interval between the two planes is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and the material is ZF6 glass.

[0130] The aforementioned heat-insulating natural light uniform illumination device, based on a composite multi-array structure, utilizes a sandwich structure of two uniform light substrates and an infrared reflective layer. This structure allows natural light entering through windows during the day to be evenly distributed to every corner of the room, utilizing natural light for indoor lighting and reducing energy consumption caused by additional lighting in deep-set houses on sunny days. The infrared reflective layer effectively blocks the conduction of indoor and outdoor temperatures through the windows. When outdoor temperatures are high, it ensures indoor coolness, reducing air conditioning energy consumption; when outdoor temperatures are low, it hinders indoor heat radiation dissipation, maintaining a constant indoor temperature. This achieves energy conservation, emission reduction, and improved energy utilization efficiency, truly embodying the concept of "green building." The use of different surface combination structures breaks the symmetry of light transmission, effectively protecting indoor privacy. Furthermore, the free combination of the uniform light substrates and the infrared reflective layer reduces manufacturing complexity. The single-piece uniform light substrate is thin, lightweight, and easy to mass-produce, requiring no special materials, making it suitable for large-scale production and promotion. As a multifunctional new lighting device, the heat-insulating natural light uniform illumination device can replace lighting curtains, indoor blinds, and window glass.

[0131] Example 2

[0132] For natural light homogenizing substrates of different surface shapes, the working plane of the first homogenizing substrate always faces the incident direction of natural light, and the normal of the working plane forms an acute angle with the incident natural light. For natural light homogenizing substrates of different surface shapes, the device material is a transparent material with a transmittance of 85% or higher in the visible light band, including but not limited to glass, resin, and transparent plastic. For natural light homogenizing substrates of different surface shapes, except for the case where the first homogenizing substrate is a single plane, the array of working planes of the two homogenizing substrates is a square full-aperture array with a fill rate of 95% or higher, and the surface shapes of the two substrates correspond one-to-one, with the center position of the surface shape matching the optical axis.

[0133] For the ultraviolet shielding film, the inorganic ultraviolet shielding film is a film system composed of metal oxide nanoparticles. The inorganic metal oxide powder used includes, but is not limited to, zinc oxide, cerium dioxide, titanium dioxide, iron oxide, mica, talc, and carbon black. The particle size of the inorganic metal oxide powder in the inorganic ultraviolet shielding film is greater than 100 nm. It absorbs ultraviolet radiation energy by scattering and refracting ultraviolet rays, which excites electrons to generate free electrons and holes, thereby realizing valence electron transition and thus achieving ultraviolet radiation shielding.

[0134] For ultraviolet shielding films, the main components of the organic ultraviolet shielding film are polymer materials containing unsaturated groups in their molecular structure, including but not limited to benzophenone, benzotriazole, salicylates, oxaloyl aniline, cyanoacrylates, and triazines. Organic ultraviolet shielding films mainly achieve the purpose of shielding by absorbing ultraviolet rays. The unsaturated groups in the film strongly and selectively absorb high-heat ultraviolet rays and convert them into other forms of energy through a series of photochemical reactions or photophysical processes, thereby achieving ultraviolet shielding.

[0135] Methods for preparing ultraviolet shielding films include, but are not limited to, hydrothermal reaction, sol-gel method, vacuum evaporation, chemical vapor deposition, vacuum magnetron sputtering, and spray pyrolysis.

[0136] As attached Figure 10 As shown, this embodiment provides a composite ultraviolet-shielded natural light homogenizing lighting device based on a combination of a single plane and a convex freeform surface. It includes two homogenizing substrates arranged in an array. The first homogenizing substrate has a single plane as its working surface, and the second homogenizing substrate has a convex freeform surface array as its working surface. The single plane collects outdoor natural light, filters UVA and UVB through an ultraviolet-shielding film, and the filtered light is then conducted to the convex freeform surface array via an intermediate medium. The convex freeform surface array deflects the incident natural light into the indoor space after refraction through its inclined surfaces. Each convex freeform surface array includes n unit structures, where n is a natural number greater than or equal to 1.

[0137] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the individual unit structure of the convex free-surface array is a convex free-form surface, and the thickness d1 at different positions (x, y) on the convex free-form surface is expressed as follows: r is the radius of curvature of the surface, θ is the tilt angle, and the surface shape can be spherical or other shapes. The radius of curvature is 1-5 times the minimum distance between the plane and the convex freeform surface. The convex freeform surface array adds phase modulation to the incident light. It can be represented as (x,y) represents the position of the incident wavefront of the freeform surface array, f is the focal length of the equivalent lens in the freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident light angle.

[0138] More specifically: the convex freeform surface array is a square full-aperture array with a fill rate of over 95%.

[0139] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0140] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the convex freeform surface has a radius r = -1mm, a surface tilt angle θ = 45°, a spacing of 1.5mm between the two uniform light substrate working surfaces, an array size of 1mm*1mm, a 5*5 array, and ZF6 glass as the material.

[0141] As attached Figure 11 As shown, this embodiment provides a composite ultraviolet-shielded homogenizing lighting device based on a combination of a single-plane and a convex lens. It includes two homogenizing substrates arranged in an array. The first homogenizing substrate has a single-plane working surface, and the second homogenizing substrate has a convex lens array working surface. The single-plane is used to collect outdoor natural light, which is filtered for UVA and UVB by an ultraviolet-shielding film. The filtered light is then transmitted to the convex lens array through an intermediate medium. The convex lens array is used to deflect the incident natural light into the indoor space after refraction through an inclined surface. Each convex lens array includes n unit structures, where n is a natural number greater than or equal to 1.

[0142] More specifically: the two arrayed surfaces respectively modulate different phases of the incident light. Specifically, the individual unit structure of the convex lens array is a convex lens, and the expression for the thickness d2 at different positions (x, y) on the convex lens is: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the plane and the convex lens. The convex lens array adds phase modulation to the incident light. It can be represented as (x,y) represents the position of the incident wavefront of the lens array, f is the focal length of the lens, and λ is the center wavelength of natural light.

[0143] More specifically: the convex lens array is a square full-aperture array with a fill rate of over 95%.

[0144] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0145] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the focal length of the convex lens is f = 5mm, the interval between the two uniform light substrate working surfaces is 1.5mm, the array size is 1mm*1mm, a 5*5 array is selected, and ZF6 glass is selected as the material.

[0146] As attached Figure 12 As shown, this embodiment provides a composite ultraviolet-shielded natural light homogenizing lighting device based on a combination of a single-plane and a sawtooth grating. It includes two homogenizing substrates arranged in a front and rear array. The first homogenizing substrate has a single-plane working surface, and the second homogenizing substrate has a sawtooth surface array. The single-plane substrate collects outdoor natural light, filters UVA and UVB through an ultraviolet-shielding film, and the filtered light is then conducted to the sawtooth surface array via an intermediate medium. The sawtooth surface array deflects the incident natural light into the indoor space after refraction through its inclined surfaces. Each sawtooth surface array comprises n unit structures, where n is a natural number greater than or equal to 1.

[0147] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the thickness d3 at different positions (x, y) on a single structural unit of the sawtooth surface array is expressed as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating. The sawtooth surface array adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y is the position of the incident wavefront of the sawtooth surface array, and θ1 is the incident light angle.

[0148] More specifically: the serrated surface array is a square full-aperture array with a fill rate of over 95%.

[0149] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0150] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the tilt angle of the sawtooth surface array grating is θ = 45°, the interval between the two planes is 1.5mm, the array size is 1mm*1mm, a 5*5 array is selected, and ZF6 glass is selected as the material to simulate the light divergence effect.

[0151] As attached Figure 13As shown, this embodiment provides a composite ultraviolet-shielded natural light homogenizing lighting device based on a combination of convex lenses and convex freeform surfaces. It includes two homogenizing substrates arranged in arrays. The first homogenizing substrate has a convex lens array as its working surface, and the second homogenizing substrate has a convex freeform surface array as its working surface. The convex lens array collects outdoor natural light, filters UVA and UVB through an ultraviolet shielding film, and then transmits the filtered light through an intermediate medium to the convex freeform surface array. The convex freeform surface array deflects the incident natural light into the indoor space after refraction through its inclined surface. Both the convex lens array and the convex freeform surface array include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0152] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the convex lens array surface of the first homogenizing substrate adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the lens array, λ is the incident wavelength (usually the center wavelength), and f is the focal length of the lens. The convex freeform surface array of the second homogenizing substrate adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the freeform surface array, f2 is the equivalent focal length of the convex freeform surface, and θ1 is the incident light angle.

[0153] More specifically: the lens surface of the convex lens faces the direction of natural light incident, and the normal of the lens surface forms an acute angle with the angle of the incident natural light. Natural light incident from a high angle outside can be dispersed in parallel to all corners of the room after passing through the designed device.

[0154] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the lens array and the freeform surface array. The convex freeform surface array refracts most of the light rays in the horizontal direction through refraction. The expression for the thickness d1 at different positions (x2, y2) on the convex freeform surface is: Where n is the refractive index, r is the radius of curvature of the vertex, and θ2 is the surface tilt angle, which allows light to propagate horizontally through refraction.

[0155] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0156] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0157] More specifically: To verify the effectiveness of the device described above, the convex lens array uses spherical lenses with a radius of curvature r = 1 mm and a focal length f = 2 mm; the convex freeform surface has a radius of curvature r = -1 mm and a surface tilt angle θ2 = 45°. The interval between the convex lens array and the convex freeform surface array is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is used, and ZF6 glass is selected as the material.

[0158] As attached Figure 14 As shown, this embodiment provides a composite ultraviolet-shielded natural light homogenizing lighting device based on a combination of two convex lenses. It includes two homogenizing substrates arranged in a front and rear array. The working surfaces of both the first and second homogenizing substrates are convex lens arrays. The first convex lens array collects outdoor natural light, filters UVA and UVB through an ultraviolet-shielding film, and then transmits the filtered light through an intermediate medium to the second convex lens array. The second convex lens array deflects the incident natural light into the indoor space after refraction through an inclined surface. Both convex lens arrays include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0159] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the convex lens array surface adds phase modulation to the incident light. It can be represented as (x1,y1) represents the position of the incident wavefront of the lens array, λ represents the incident wavelength (usually the center wavelength), and f represents the focal length of the lens.

[0160] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The focal length of the second convex lens array is 2-5 times that of the first convex lens array. The second convex lens refracts most of the light rays in the horizontal direction.

[0161] More specifically: a convex lens facing the direction of natural light, with the normal of the lens surface forming an acute angle with the angle of the incident natural light, allows natural light incident from a high angle outdoors to be diffused in parallel to all corners of the room through the designed device. Specifically, the rear focal point of a single unit lens in the first convex lens array coincides with the front focal point of a single unit lens in the second convex lens array, forming a Keplerian telescope structure that diffuses light into the indoor space.

[0162] More specifically, the unit sizes of the second convex lens array and the first convex lens array are not equal. The size of a single unit lens in the second convex lens array is such that it can collect and converge all the beams of the corresponding unit of the first positive lens array.

[0163] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0164] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex lens is selected as a unit lens with a focal length of 2mm, the second convex lens is selected as a unit lens with a focal length of 5mm, and the distance between the first convex lens and the second convex lens is 7mm.

[0165] As attached Figure 15 As shown, this embodiment provides a composite ultraviolet-shielded natural light homogenizing lighting device based on a combination of convex lenses and sawtooth gratings. It includes two homogenizing substrates arranged in a front and rear array. The working surface of the first homogenizing substrate is a convex lens array, and the working surface of the second homogenizing substrate is a sawtooth grating array. The convex lens array collects outdoor natural light, filters UVA and UVB through an ultraviolet shielding film, and the filtered light is then transmitted through an intermediate medium to the convex freeform surface array. The sawtooth grating array deflects the incident natural light into the indoor space after refraction through an inclined surface. Both the convex lens array and the sawtooth grating array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0166] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the convex lens array surface of the first homogenizing substrate adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the lens array, λ is the incident wavelength (usually the center wavelength), and f is the focal length of the lens. The sawtooth grating array surface of the second homogenizing substrate adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y2 is the position of the incident wavefront of the sawtooth surface array, and θ1 is the incident light angle.

[0167] More specifically: the lens surface of the convex lens faces the direction of natural light incident, and the normal of the lens surface forms an acute angle with the angle of the incident natural light. Natural light incident from a high angle outside can be dispersed in parallel to all corners of the room after passing through the designed device.

[0168] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum spacing between the lens array and the sawtooth grating array. The expression for the thickness d at different positions (x2, y2) on a single structural unit of the sawtooth surface array is as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, which causes light to propagate horizontally through refraction.

[0169] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0170] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0171] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the convex lens array is selected from spherical lenses with a radius of curvature of r = 1 mm and a focal length of f = 2 mm; the sawtooth grating tilt angle θ = 45°, the lens array and the sawtooth grating are in one-to-one correspondence, the interval between the two planes is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and the material is ZF6 glass.

[0172] As attached Figure 16 As shown, this embodiment provides a composite ultraviolet-shielded natural light homogenizing lighting device based on a combination of freeform convex and convex surfaces. It includes two homogenizing substrates arranged in front and behind arrays. Both the working surfaces of the first and second homogenizing substrates are convex freeform surfaces. Outdoor high-angle natural light is collected by the first convex freeform surface array, filtered for UVA and UVB by an ultraviolet shielding film, and then transmitted to the convex freeform surface array via an intermediate medium. The second convex freeform surface array deflects the incident natural light into the indoor space after refraction through its inclined surface. Both the first and second convex freeform surface arrays include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0173] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second convex freeform surface array adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the freeform surface array, f2 represents the equivalent lens focal length in the second convex freeform surface array, λ represents the center wavelength of natural light, and θ2 represents the incident angle of the incident light on the first convex freeform surface.

[0174] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other shapes. The radius of curvature is 1-5 times the minimum spacing between the two convex freeform surface arrays. The expression for the thickness d2 at different positions (x2, y2) on the second convex freeform surface is as follows: r2 is the radius of the surface, α2 is the inclination angle of the second convex freeform surface, and the surface form can be a sphere, a parabola, or other forms. The radius of the surface is 1-5 times the minimum spacing between the two convex freeform surface arrays.

[0175] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0176] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0177] More specifically: To verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm and a surface tilt angle of α1 = 10°, the second convex freeform surface array has a radius of curvature of r2 = -1 mm and a surface tilt angle of α2 = 35°, the first convex freeform surface lens array and the second convex freeform surface lens array correspond one-to-one, the interval between the two planes is 1.2 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and ZF6 glass is selected as the material.

[0178] As attached Figure 17 As shown, this embodiment provides a composite ultraviolet-shielded natural light homogenizing lighting device based on a convex freeform surface and a convex lens array. It includes two homogenizing substrates arranged in a front and rear array configuration. The working surface of the first homogenizing substrate is a convex freeform surface, and the working surface of the second homogenizing substrate is a convex lens. Outdoor high-angle natural light is collected by the convex freeform surface array, filtered for UVA and UVB by an ultraviolet shielding film, and then transmitted through an intermediate medium to the convex lens array. The convex lens array is used to deflect the incident natural light into the indoor space after refraction through the inclined surface. Both the convex freeform surface array and the convex lens array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0179] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second convex lens array surface adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the lens array, λ represents the center wavelength of the incident natural light, and f2 represents the focal length of the lens.

[0180] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other shapes. The radius of curvature is 1-5 times the minimum distance between the lens array and the freeform surface array. The expression for the thickness d2 at different positions (x2, y2) on the second convex lens is as follows:

[0181] r2 is the radius of the surface. The surface shape can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the lens array and the freeform surface array.

[0182] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0183] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0184] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm and a surface tilt angle of α1 = 10°. The second convex lens array has a focal length of f = 5 mm. The first convex freeform surface array and the second convex lens array correspond one-to-one. The interval between the two planes is 1.5 mm. The array size is 1 mm * 1 mm. A 5 * 5 array is selected. ZF6 glass is selected as the material.

[0185] As attached Figure 18As shown, this embodiment provides a composite ultraviolet-shielded natural light homogenizing lighting device based on a convex freeform surface and a sawtooth grating array. It includes two homogenizing substrates in the form of arrays, one at the front and one at the back. The working surface of the first homogenizing substrate is a convex freeform surface, and the working surface of the second homogenizing substrate is a sawtooth grating surface. Outdoor high-angle natural light is collected by the convex freeform surface array, filtered for UVA and UVB by an ultraviolet shielding film, and then transmitted through an intermediate medium to the sawtooth grating array. The sawtooth grating array is used to deflect the incident natural light into the indoor space after refraction through the inclined surface. Both the convex freeform surface array and the sawtooth grating array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0186] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second sawtooth grating array surface adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y2 is the position of the incident wavefront of the sawtooth surface array, and θ2 is the incident light angle.

[0187] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other forms. The radius of curvature is 1-5 times the minimum distance between the lens array and the freeform surface array. The expression for the thickness d at different positions (x2, y2) on a single structural unit of the sawtooth surface array is as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, which causes light to propagate horizontally through refraction.

[0188] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0189] More specifically: the main component of the ultraviolet shielding film is nano-titanium dioxide, which macroscopically appears as a thin film with a thickness of less than 0.1 mm.

[0190] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm, a surface tilt angle of α1 = 10°, a sawtooth grating surface tilt angle of θ = 35°, the convex freeform surface array and the sawtooth grating array correspond one-to-one, the interval between the two planes is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and the material is ZF6 glass.

[0191] This composite multi-array ultraviolet-shielded natural light uniform illumination device, through a sandwich structure of two uniform light substrates and an ultraviolet-shielding film, allows natural light entering from windows during the day to be evenly distributed to every corner of the room, utilizing natural light for indoor lighting and reducing energy consumption caused by additional lighting in deep-set houses on sunny days. The ultraviolet-shielding film effectively blocks the transmission of ultraviolet rays from natural light through windows, preventing damage to human skin and indoor furnishings caused by long-term exposure to ultraviolet rays. The overall device improves energy efficiency, truly practicing the concept of "green building." Due to the use of different surface combination structures, the symmetry of light transmission is broken, which can effectively protect indoor privacy. In addition, the free combination of uniform light substrates and ultraviolet-shielding film reduces manufacturing complexity. The single-piece uniform light substrate is thin and easy to mass-produce, with no special material requirements, making it suitable for large-scale production and promotion. As a multifunctional new lighting device, the ultraviolet-shielded natural light uniform illumination device can replace lighting curtains, indoor blinds, and window glass.

[0192] Example 3

[0193] For natural light homogenizing substrates of different surface shapes, the working plane of the first homogenizing substrate always faces the incident direction of natural light, and the normal of the working plane forms an acute angle with the incident natural light. For natural light homogenizing substrates of different surface shapes, the device material is a transparent material with a transmittance of 85% or higher in the visible light band, including but not limited to glass, resin, and transparent plastic. For natural light homogenizing substrates of different surface shapes, except for the case where the first homogenizing substrate is a single plane, the array of working planes of the two homogenizing substrates is a square full-aperture array with a fill rate of 95% or higher, and the surface shapes of the two substrates correspond one-to-one, with the center position of the surface shape matching the optical axis.

[0194] For photochromic coatings, the inorganic photochromic coatings mainly consist of, but are not limited to, transition metal oxides, polyoxometalates, metal halides, and rare earth complexes. The main mechanism of color change is the electron transition and charge transfer within the material's crystal lattice under specific wavelength irradiation. This process is reversible, and the material can return to its initial state after the irradiation conditions change. For photochromic coatings, the organic photochromic coatings mainly consist of polymeric materials with specific chemical functional groups in their molecular structure, including but not limited to spiropyrans, spirozines, azobenzenes, diarylethylenes, succinic anhydrides, viologens, and Schiff bases. Different functional groups determine the performance of the photochromic coating, namely, the color exhibited by the film under strong sunlight irradiation, its sensitivity to sunlight, and its fatigue resistance. Methods for preparing photochromic coating films include, but are not limited to, sol-gel methods, ion exchange methods, chemical vapor deposition methods, vacuum magnetron sputtering methods, and spray pyrolysis methods.

[0195] As attached Figure 19 As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing lighting device based on a combination of a single plane and a convex freeform surface. It includes two homogenizing substrates arranged in an array. The first homogenizing substrate has a single plane as its working surface, and the second homogenizing substrate has a convex freeform surface array as its working surface. The single plane collects outdoor natural light, which is then filtered by a photochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the convex freeform surface array. The convex freeform surface array deflects the incident natural light through its inclined surfaces into the indoor space. Each convex freeform surface array includes n unit structures, where n is a natural number greater than or equal to 1.

[0196] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the individual unit structure of the convex free-surface array is a convex free-form surface, and the thickness d1 at different positions (x, y) on the convex free-form surface is expressed as follows: r is the radius of curvature of the surface, θ is the tilt angle, and the surface shape can be spherical or other shapes. The radius of curvature is 1-5 times the minimum distance between the plane and the convex freeform surface. The convex freeform surface array adds phase modulation to the incident light. It can be represented as (x,y) represents the position of the incident wavefront of the freeform surface array, f is the focal length of the equivalent lens in the freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident light angle.

[0197] More specifically: the convex freeform surface array is a square full-aperture array with a fill rate of over 95%.

[0198] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0199] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the convex freeform surface has a radius r = -1mm, a surface tilt angle θ = 45°, a spacing of 1.5mm between the two uniform light substrate working surfaces, an array size of 1mm*1mm, a 5*5 array, and ZF6 glass as the material.

[0200] As attached Figure 20 As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing lighting device based on a combination of a single plane and convex lenses. It includes two homogenizing substrates arranged in an array. The first homogenizing substrate has a single plane as its working surface, and the second homogenizing substrate has a convex lens array as its working surface. The single plane collects outdoor natural light, which is then filtered by a photochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted to the convex lens array through an intermediate medium. The convex lens array deflects the incident natural light into the indoor space after refraction through an inclined surface. Each convex lens array includes n unit structures, where n is a natural number greater than or equal to 1.

[0201] More specifically: the two arrayed surfaces respectively modulate different phases of the incident light. Specifically, the individual unit structure of the convex lens array is a convex lens, and the expression for the thickness d2 at different positions (x, y) on the convex lens is: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the plane and the convex lens. The convex lens array adds phase modulation to the incident light. It can be represented as (x,y) represents the position of the incident wavefront of the lens array, f is the focal length of the lens, and λ is the center wavelength of natural light.

[0202] More specifically: the convex lens array is a square full-aperture array with a fill rate of over 95%.

[0203] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0204] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the focal length of the convex lens is f = 5mm, the interval between the two uniform light substrate working surfaces is 1.5mm, the array size is 1mm*1mm, a 5*5 array is selected, and ZF6 glass is selected as the material.

[0205] As attached Figure 21As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing lighting device based on a combination of a single-plane and a sawtooth grating. It includes two homogenizing substrates arranged in a front and rear array. The first homogenizing substrate has a single-plane working surface, and the second homogenizing substrate has a sawtooth surface array. The single-plane substrate collects outdoor natural light, which is then filtered by a photochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the sawtooth surface array. The sawtooth surface array deflects the incident natural light into the indoor space after refraction through the inclined surface. Each sawtooth surface array includes n unit structures, where n is a natural number greater than or equal to 1.

[0206] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the thickness d3 at different positions (x, y) on a single structural unit of the sawtooth surface array is expressed as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating. The sawtooth surface array adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y is the position of the incident wavefront of the sawtooth surface array, and θ1 is the incident light angle.

[0207] More specifically: the serrated surface array is a square full-aperture array with a fill rate of over 95%.

[0208] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0209] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the tilt angle of the sawtooth surface array grating is θ = 45°, the interval between the two planes is 1.5mm, the array size is 1mm*1mm, a 5*5 array is selected, and ZF6 glass is selected as the material to simulate the light divergence effect.

[0210] As attached Figure 22 As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing illumination device based on a combination of convex lenses and convex freeform surfaces. It includes two homogenizing substrates arranged in a front and rear array. The working surface of the first homogenizing substrate is a convex lens array, and the working surface of the second homogenizing substrate is a convex freeform surface array. The convex lens array collects outdoor natural light, which is then filtered by a photochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the convex freeform surface array. The convex freeform surface array deflects the incident natural light into the indoor space after refraction through its inclined surface. Both the convex lens array and the convex freeform surface array include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0211] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the convex lens array surface of the first homogenizing substrate adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the lens array, λ is the incident wavelength (usually the center wavelength), and f is the focal length of the lens. The convex freeform surface array of the second homogenizing substrate adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the freeform surface array, f2 is the equivalent focal length of the convex freeform surface, and θ1 is the incident light angle.

[0212] More specifically: the lens surface of the convex lens faces the direction of natural light incident, and the normal of the lens surface forms an acute angle with the angle of the incident natural light. Natural light incident from a high angle outside can be dispersed in parallel to all corners of the room after passing through the designed device.

[0213] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the lens array and the freeform surface array. The convex freeform surface array refracts most of the light rays in the horizontal direction through refraction. The expression for the thickness d1 at different positions (x2, y2) on the convex freeform surface is: Where n is the refractive index, r is the radius of curvature of the vertex, and θ2 is the surface tilt angle, which allows light to propagate horizontally through refraction.

[0214] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0215] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0216] More specifically: To verify the effectiveness of the device described above, the convex lens array uses spherical lenses with a radius of curvature r = 1 mm and a focal length f = 2 mm; the convex freeform surface has a radius of curvature r = -1 mm and a surface tilt angle θ2 = 45°. The interval between the convex lens array and the convex freeform surface array is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is used, and ZF6 glass is selected as the material.

[0217] As attached Figure 23As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing lighting device based on a combination of two convex lenses. It includes two homogenizing substrates arranged in a front and rear array. The working surfaces of both the first and second homogenizing substrates are convex lens arrays. The first convex lens array collects outdoor natural light, which is then filtered by a photochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the second convex lens array. The second convex lens array deflects the incident natural light through a tilted surface into the indoor space. Both convex lens arrays include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0218] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the convex lens array surface adds phase modulation to the incident light. It can be represented as (x1,y1) represents the position of the incident wavefront of the lens array, λ represents the incident wavelength (usually the center wavelength), and f represents the focal length of the lens.

[0219] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The focal length of the second convex lens array is 2-5 times that of the first convex lens array. The second convex lens refracts most of the light rays in the horizontal direction.

[0220] More specifically: a convex lens facing the direction of natural light, with the normal of the lens surface forming an acute angle with the angle of the incident natural light, allows natural light incident from a high angle outdoors to be diffused in parallel to all corners of the room through the designed device. Specifically, the rear focal point of a single unit lens in the first convex lens array coincides with the front focal point of a single unit lens in the second convex lens array, forming a Keplerian telescope structure that diffuses light into the indoor space.

[0221] More specifically, the unit sizes of the second convex lens array and the first convex lens array are not equal. The size of a single unit lens in the second convex lens array is such that it can collect and converge all the beams of the corresponding unit of the first positive lens array.

[0222] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0223] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex lens is selected as a unit lens with a focal length of 2mm, the second convex lens is selected as a unit lens with a focal length of 5mm, and the distance between the first convex lens and the second convex lens is 7mm.

[0224] As attached Figure 24As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing illumination device based on a combination of convex lenses and sawtooth gratings. It includes two homogenizing substrates arranged in a front and rear array. The working surface of the first homogenizing substrate is a convex lens array, and the working surface of the second homogenizing substrate is a sawtooth grating array. The convex lens array collects outdoor natural light, which is then filtered by a photochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the convex freeform surface array. The sawtooth grating array deflects the incident natural light through a tilted surface into the indoor space. Both the convex lens array and the sawtooth grating array include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0225] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the convex lens array surface of the first homogenizing substrate adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the lens array, λ is the incident wavelength (usually the center wavelength), and f is the focal length of the lens. The sawtooth grating array surface of the second homogenizing substrate adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y2 is the position of the incident wavefront of the sawtooth surface array, and θ1 is the incident light angle.

[0226] More specifically: the lens surface of the convex lens faces the direction of natural light incident, and the normal of the lens surface forms an acute angle with the angle of the incident natural light. Natural light incident from a high angle outside can be dispersed in parallel to all corners of the room after passing through the designed device.

[0227] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum spacing between the lens array and the sawtooth grating array. The expression for the thickness d at different positions (x2, y2) on a single structural unit of the sawtooth surface array is as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, which causes light to propagate horizontally through refraction.

[0228] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0229] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0230] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the convex lens array is selected from spherical lenses with a radius of curvature of r = 1 mm and a focal length of f = 2 mm; the sawtooth grating tilt angle θ = 45°, the lens array and the sawtooth grating are in one-to-one correspondence, the interval between the two planes is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and the material is ZF6 glass.

[0231] As attached Figure 25 As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing lighting device based on a combination of freeform convex and convex surfaces. It includes two homogenizing substrates arranged in front and behind arrays. Both the working surfaces of the first and second homogenizing substrates are convex freeform surfaces. Outdoor high-angle natural light is collected by the first convex freeform surface array, and the transmittance and reflectance of the homogenizing device are adjusted by a photochromic layer. The filtered light is then transmitted to the convex freeform surface array through an intermediate medium. The second convex freeform surface array is used to deflect the incident natural light into the indoor space after refraction through its inclined surface. Both the first and second convex freeform surface arrays include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0232] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second convex freeform surface array adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the freeform surface array, f2 represents the equivalent lens focal length in the second convex freeform surface array, λ represents the center wavelength of natural light, and θ2 represents the incident angle of the incident light on the first convex freeform surface.

[0233] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other shapes. The radius of curvature is 1-5 times the minimum spacing between the two convex freeform surface arrays. The expression for the thickness d2 at different positions (x2, y2) on the second convex freeform surface is as follows: r2 is the radius of the surface, α2 is the inclination angle of the second convex freeform surface, and the surface form can be a sphere, a parabola, or other forms. The radius of the surface is 1-5 times the minimum spacing between the two convex freeform surface arrays.

[0234] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0235] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0236] More specifically: To verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm and a surface tilt angle of α1 = 10°, the second convex freeform surface array has a radius of curvature of r2 = -1 mm and a surface tilt angle of α2 = 35°, the first convex freeform surface lens array and the second convex freeform surface lens array correspond one-to-one, the interval between the two planes is 1.2 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and ZF6 glass is selected as the material.

[0237] As attached Figure 26 As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing lighting device based on a convex freeform surface and a convex lens array. It includes two homogenizing substrates arranged in a front and rear array configuration. The working surface of the first homogenizing substrate is a convex freeform surface, and the working surface of the second homogenizing substrate is a convex lens. Outdoor high-angle natural light is collected by the convex freeform surface array, and the transmittance and reflectance of the homogenizing device are adjusted by a photochromic layer. The filtered light is then transmitted through an intermediate medium to the convex lens array. The convex lens array is used to deflect the incident natural light into the indoor space after refraction through the inclined surface. Both the convex freeform surface array and the convex lens array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0238] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second convex lens array surface adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the lens array, λ represents the center wavelength of the incident natural light, and f2 represents the focal length of the lens.

[0239] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other shapes. The radius of curvature is 1-5 times the minimum distance between the lens array and the freeform surface array. The expression for the thickness d2 at different positions (x2, y2) on the second convex lens is as follows: r2 is the radius of the surface. The surface shape can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the lens array and the freeform surface array.

[0240] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0241] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0242] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm and a surface tilt angle of α1 = 10°. The second convex lens array has a focal length of f = 5 mm. The first convex freeform surface array and the second convex lens array correspond one-to-one. The interval between the two planes is 1.5 mm. The array size is 1 mm * 1 mm. A 5 * 5 array is selected. ZF6 glass is selected as the material.

[0243] As attached Figure 27 As shown, this embodiment provides a composite photosensitive color-changing natural light homogenizing illumination device based on a convex freeform surface and a sawtooth grating array. It includes two homogenizing substrates in the form of arrays, one at the front and one at the back. The working surface of the first homogenizing substrate is a convex freeform surface, and the working surface of the second homogenizing substrate is a sawtooth grating surface. Outdoor high-angle natural light is collected by the convex freeform surface array, and the transmittance and reflectance of the homogenizing device are adjusted by a photochromic layer. The filtered light is then conducted to the sawtooth grating array through an intermediate medium. The sawtooth grating array is used to deflect the incident natural light into the indoor space after refraction through the inclined surface. Both the convex freeform surface array and the sawtooth grating array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0244] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second sawtooth grating array surface adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y2 is the position of the incident wavefront of the sawtooth surface array, and θ2 is the incident light angle.

[0245] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other forms. The radius of curvature is 1-5 times the minimum distance between the lens array and the freeform surface array. The expression for the thickness d at different positions (x2, y2) on a single structural unit of the sawtooth surface array is as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, which causes light to propagate horizontally through refraction.

[0246] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0247] More specifically: the main component of the photochromic coating is silver chloride, which appears macroscopically as a thin film with a thickness of less than 0.1 mm.

[0248] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm, a surface tilt angle of α1 = 10°, a sawtooth grating surface tilt angle of θ = 35°, the convex freeform surface array and the sawtooth grating array correspond one-to-one, the interval between the two planes is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and the material is ZF6 glass.

[0249] The aforementioned photosensitive color-changing natural light uniform illumination device, based on a composite multi-array structure, utilizes a sandwich structure of two uniform light substrates and a photochromic coating. This structure allows natural light entering through windows during the day to be evenly distributed to every corner of the room, utilizing natural light for indoor illumination and reducing energy consumption caused by additional lighting in deep, sunny rooms. The photochromic coating effectively blocks excessive sunlight from entering the room by regulating light entry, thus reducing glare and heat radiation intake. It features rapid color-changing and brightness recovery, and its performance shows no fatigue degradation even after repeated darkening and fading, making it promising for practical applications. The use of different surface combination structures breaks the symmetry of light transmission, effectively protecting indoor privacy. Furthermore, the free combination of the uniform light substrate and the photochromic coating reduces manufacturing complexity; the single-piece uniform light substrate is thin, lightweight, and easy to mass-produce, requiring no special materials, making it suitable for large-scale production and promotion. As a multifunctional new type of lighting device, the intelligent photosensitive color-changing natural light uniform illumination device can replace lighting curtains, indoor blinds, and window glass.

[0250] Example 4

[0251] For natural light homogenizing substrates of different surface shapes, the working plane of the first homogenizing substrate always faces the incident direction of natural light, and the normal of the working plane forms an acute angle with the incident natural light. For natural light homogenizing substrates of different surface shapes, the device material is a transparent material with a transmittance of 85% or higher in the visible light band, including but not limited to glass, resin, and transparent plastic. For natural light homogenizing substrates of different surface shapes, except for the case where the first homogenizing substrate is a single plane, the array of working planes of the two homogenizing substrates is a square full-aperture array with a fill rate of 95% or higher, and the surface shapes of the two substrates correspond one-to-one, with the center position of the surface shape matching the optical axis.

[0252] For thermochromic coatings, the main components of the inorganic reversible thermochromic coating include, but are not limited to: iodides, complexes, and double salts of mercury, copper, and silver; compounds formed by cobalt salts, nickel salts, and hexamethylenetetramine; oxides of vanadium and manganese, chromates, and mixtures thereof. The main mechanism of color change is based on the decomposition and recombination of the molecular structure of substances with changes in the external environment, thereby producing color changes, including changes in the internal crystal morphology and pH value of the material, or electron transfer caused by redox reactions. For thermochromic coatings, the main components of the organic reversible thermochromic coating include, but are not limited to: electron-donating and accepting reversible thermochromic materials composed of electron donors, electron acceptors, and solvents; polyaromatic rings containing -CH=CH-; Shiff bases; polydiyne compounds; and polythiophene compounds. Electron-donating and accepting reversible thermochromic materials cause changes in the molecular structure of organic matter through electron transfer, and radiate or absorb light of different wavelengths, thereby causing reversible color changes; other organic reversible thermochromic materials have molecular isomerization combinations to generate new substances, and the internal molecular structure balance changes with temperature changes, and the color also changes accordingly. Methods for preparing thermochromic coatings include, but are not limited to, sol-gel method, vacuum evaporation method, photopolymerization method, interfacial solvent exchange method, and self-assembly method.

[0253] As attached Figure 28 As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a combination of a single plane and a convex freeform surface. It includes two homogenizing substrates arranged in an array. The first homogenizing substrate has a single plane as its working surface, and the second homogenizing substrate has a convex freeform surface array as its working surface. The single plane collects outdoor natural light, which is then filtered by a thermochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then conducted through an intermediate medium to the convex freeform surface array. The convex freeform surface array deflects the incident natural light through its inclined surfaces into the indoor space. Each convex freeform surface array includes n unit structures, where n is a natural number greater than or equal to 1.

[0254] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the individual unit structure of the convex free-surface array is a convex free-form surface, and the thickness d1 at different positions (x, y) on the convex free-form surface is expressed as follows: r is the radius of curvature of the surface, θ is the tilt angle, and the surface shape can be spherical or other shapes. The radius of curvature is 1-5 times the minimum distance between the plane and the convex freeform surface. The convex freeform surface array adds phase modulation to the incident light. It can be represented as (x,y) represents the position of the incident wavefront of the freeform surface array, f is the focal length of the equivalent lens in the freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident light angle.

[0255] More specifically: the convex freeform surface array is a square full-aperture array with a fill rate of over 95%.

[0256] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0257] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the convex freeform surface has a radius r = -1mm, a surface tilt angle θ = 45°, a spacing of 1.5mm between the two uniform light substrate working surfaces, an array size of 1mm*1mm, a 5*5 array, and ZF6 glass as the material.

[0258] As attached Figure 29 As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a combination of a single plane and convex lenses. It includes two homogenizing substrates arranged in an array. The first homogenizing substrate has a single plane as its working surface, and the second homogenizing substrate has a convex lens array as its working surface. The single plane collects outdoor natural light, which is then filtered by a thermochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the convex lens array. The convex lens array deflects the incident natural light through an inclined surface into the indoor space. Each convex lens array includes n unit structures, where n is a natural number greater than or equal to 1.

[0259] More specifically: the two arrayed surfaces respectively modulate different phases of the incident light. Specifically, the individual unit structure of the convex lens array is a convex lens, and the expression for the thickness d2 at different positions (x, y) on the convex lens is: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the plane and the convex lens. The convex lens array adds phase modulation to the incident light. It can be represented as (x,y) represents the position of the incident wavefront of the lens array, f is the focal length of the lens, and λ is the center wavelength of natural light.

[0260] More specifically: the convex lens array is a square full-aperture array with a fill rate of over 95%.

[0261] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0262] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the focal length of the convex lens is f = 5mm, the interval between the two uniform light substrate working surfaces is 1.5mm, the array size is 1mm*1mm, a 5*5 array is selected, and ZF6 glass is selected as the material.

[0263] As attached Figure 30 As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a combination of a single-plane and a sawtooth grating. It includes two homogenizing substrates arranged in a front and rear array. The first homogenizing substrate has a single-plane working surface, and the second homogenizing substrate has a sawtooth surface array. The single-plane substrate collects outdoor natural light, which is then filtered by a thermochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the sawtooth surface array. The sawtooth surface array deflects the incident natural light into the indoor space after refraction through the inclined surface. Each sawtooth surface array comprises n unit structures, where n is a natural number greater than or equal to 1.

[0264] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the thickness d3 at different positions (x, y) on a single structural unit of the sawtooth surface array is expressed as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating. The sawtooth surface array adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y is the position of the incident wavefront of the sawtooth surface array, and θ1 is the incident light angle.

[0265] More specifically: the serrated surface array is a square full-aperture array with a fill rate of over 95%.

[0266] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0267] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the tilt angle of the sawtooth surface array grating is θ = 45°, the interval between the two planes is 1.5mm, the array size is 1mm*1mm, a 5*5 array is selected, and ZF6 glass is selected as the material to simulate the light divergence effect.

[0268] As attached Figure 31 As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a combination of convex lenses and convex freeform surfaces. It includes two homogenizing substrates arranged in arrays. The first homogenizing substrate has a convex lens array as its working surface, and the second homogenizing substrate has a convex freeform surface array as its working surface. The convex lens array collects outdoor natural light, which is then filtered by a thermochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the convex freeform surface array. The convex freeform surface array deflects the incident natural light through its inclined surface into the indoor space. Both the convex lens array and the convex freeform surface array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0269] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the convex lens array surface of the first homogenizing substrate adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the lens array, λ is the incident wavelength (usually the center wavelength), and f is the focal length of the lens. The convex freeform surface array of the second homogenizing substrate adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the freeform surface array, f2 is the equivalent focal length of the convex freeform surface, and θ1 is the incident light angle.

[0270] More specifically: the lens surface of the convex lens faces the direction of natural light incident, and the normal of the lens surface forms an acute angle with the angle of the incident natural light. Natural light incident from a high angle outside can be dispersed in parallel to all corners of the room after passing through the designed device.

[0271] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the lens array and the freeform surface array. The convex freeform surface array refracts most of the light rays in the horizontal direction through refraction. The expression for the thickness d1 at different positions (x2, y2) on the convex freeform surface is: Where n is the refractive index, r is the radius of curvature of the vertex, and θ2 is the surface tilt angle, which allows light to propagate horizontally through refraction.

[0272] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0273] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0274] More specifically: To verify the effectiveness of the device described above, the convex lens array uses spherical lenses with a radius of curvature r = 1 mm and a focal length f = 2 mm; the convex freeform surface has a radius of curvature r = -1 mm and a surface tilt angle θ2 = 45°. The interval between the convex lens array and the convex freeform surface array is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is used, and ZF6 glass is selected as the material.

[0275] As attached Figure 32 As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a combination of two convex lenses. It includes two homogenizing substrates arranged in arrays, one in front and one behind. The working surfaces of both the first and second homogenizing substrates are convex lens arrays. The first convex lens array collects outdoor natural light, which is then filtered by a thermochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the second convex lens array. The second convex lens array deflects the incident natural light through a tilted surface into the indoor space. Both convex lens arrays include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0276] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the convex lens array surface adds phase modulation to the incident light. It can be represented as (x1,y1) represents the position of the incident wavefront of the lens array, λ represents the incident wavelength (usually the center wavelength), and f represents the focal length of the lens.

[0277] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The focal length of the second convex lens array is 2-5 times that of the first convex lens array. The second convex lens refracts most of the light rays in the horizontal direction.

[0278] More specifically: a convex lens facing the direction of natural light, with the normal of the lens surface forming an acute angle with the angle of the incident natural light, allows natural light incident from a high angle outdoors to be diffused in parallel to all corners of the room through the designed device. Specifically, the rear focal point of a single unit lens in the first convex lens array coincides with the front focal point of a single unit lens in the second convex lens array, forming a Keplerian telescope structure that diffuses light into the indoor space.

[0279] More specifically, the unit sizes of the second convex lens array and the first convex lens array are not equal. The size of a single unit lens in the second convex lens array is such that it can collect and converge all the beams of the corresponding unit of the first positive lens array.

[0280] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0281] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex lens is selected as a unit lens with a focal length of 2mm, the second convex lens is selected as a unit lens with a focal length of 5mm, and the distance between the first convex lens and the second convex lens is 7mm.

[0282] As attached Figure 33 As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a combination of convex lenses and sawtooth gratings. It includes two homogenizing substrates arranged in a front and rear array configuration. The first homogenizing substrate has a convex lens array as its working surface, and the second homogenizing substrate has a sawtooth grating array as its working surface. The convex lens array collects outdoor natural light, which is then filtered by a thermochromic layer to adjust the transmittance and reflectance of the homogenizing device. The filtered light is then transmitted through an intermediate medium to the convex freeform surface array. The sawtooth grating array deflects the incident natural light through a tilted surface into the indoor space. Both the convex lens array and the sawtooth grating array include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0283] More specifically: the two array-shaped surfaces respectively modulate different phases of the incident light. Specifically, the convex lens array surface of the first homogenizing substrate adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the lens array, λ is the incident wavelength (usually the center wavelength), and f is the focal length of the lens. The sawtooth grating array surface of the second homogenizing substrate adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y2 is the position of the incident wavefront of the sawtooth surface array, and θ1 is the incident light angle.

[0284] More specifically: the lens surface of the convex lens faces the direction of natural light incident, and the normal of the lens surface forms an acute angle with the angle of the incident natural light. Natural light incident from a high angle outside can be dispersed in parallel to all corners of the room after passing through the designed device.

[0285] More specifically: the expression for the thickness z at different positions (x1, y1) on the convex lens is as follows: r is the radius of the surface, which can be spherical or other shapes. The radius of the surface is 1-5 times the minimum spacing between the lens array and the sawtooth grating array. The expression for the thickness d at different positions (x2, y2) on a single structural unit of the sawtooth surface array is as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, which causes light to propagate horizontally through refraction.

[0286] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0287] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0288] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the convex lens array is selected from spherical lenses with a radius of curvature of r = 1 mm and a focal length of f = 2 mm; the sawtooth grating tilt angle θ = 45°, the lens array and the sawtooth grating are in one-to-one correspondence, the interval between the two planes is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and the material is ZF6 glass.

[0289] As attached Figure 34As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a combination of freeform convex and convex surfaces. It includes two homogenizing substrates arranged in arrays, one in front and one behind. Both the working surfaces of the first and second homogenizing substrates are convex freeform surfaces. Outdoor high-angle natural light is collected by the first convex freeform surface array, and the transmittance and reflectance of the homogenizing device are adjusted by a thermochromic layer. The filtered light is then conducted to the convex freeform surface array through an intermediate medium. The second convex freeform surface array deflects the incident natural light into the indoor space after refraction through its inclined surface. Both the first and second convex freeform surface arrays include n unit structures, which are in one-to-one correspondence, where n is a natural number greater than or equal to 1.

[0290] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second convex freeform surface array adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the freeform surface array, f2 represents the equivalent lens focal length in the second convex freeform surface array, λ represents the center wavelength of natural light, and θ2 represents the incident angle of the incident light on the first convex freeform surface.

[0291] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other shapes. The radius of curvature is 1-5 times the minimum spacing between the two convex freeform surface arrays. The expression for the thickness d2 at different positions (x2, y2) on the second convex freeform surface is as follows: r2 is the radius of the surface, α2 is the inclination angle of the second convex freeform surface, and the surface form can be a sphere, a parabola, or other forms. The radius of the surface is 1-5 times the minimum spacing between the two convex freeform surface arrays.

[0292] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0293] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0294] More specifically: To verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm and a surface tilt angle of α1 = 10°, the second convex freeform surface array has a radius of curvature of r2 = -1 mm and a surface tilt angle of α2 = 35°, the first convex freeform surface lens array and the second convex freeform surface lens array correspond one-to-one, the interval between the two planes is 1.2 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and ZF6 glass is selected as the material.

[0295] As attached Figure 35 As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a convex freeform surface and a convex lens array. It includes two homogenizing substrates arranged in a front and rear array configuration. The first homogenizing substrate has a convex freeform surface as its working surface, and the second homogenizing substrate has a convex lens as its working surface. Outdoor high-angle natural light is collected by the convex freeform surface array, and the transmittance and reflectance of the homogenizing device are adjusted by a thermochromic layer. The filtered light is then transmitted through an intermediate medium to the convex lens array. The convex lens array is used to deflect the incident natural light into the indoor space after refraction through the inclined surface. Both the convex freeform surface array and the convex lens array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0296] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second convex lens array surface adds phase modulation to the incident light. It can be represented as (x2,y2) represents the position of the incident wavefront of the lens array, λ represents the center wavelength of the incident natural light, and f2 represents the focal length of the lens.

[0297] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other shapes. The radius of curvature is 1-5 times the minimum distance between the lens array and the freeform surface array. The expression for the thickness d2 at different positions (x2, y2) on the second convex lens is as follows: r2 is the radius of the surface. The surface shape can be spherical or other shapes. The radius of the surface is 1-5 times the minimum distance between the lens array and the freeform surface array.

[0298] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0299] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0300] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm and a surface tilt angle of α1 = 10°. The second convex lens array has a focal length of f = 5 mm. The first convex freeform surface array and the second convex lens array correspond one-to-one. The interval between the two planes is 1.5 mm. The array size is 1 mm * 1 mm. A 5 * 5 array is selected. ZF6 glass is selected as the material.

[0301] As attached Figure 36 As shown, this embodiment provides a composite thermochromic natural light homogenizing lighting device based on a convex freeform surface and a sawtooth grating array. It includes two homogenizing substrates arranged in arrays, with the first substrate having a convex freeform surface as its working surface and the second substrate having a sawtooth grating surface as its working surface. Outdoor high-angle natural light is collected by the convex freeform surface array, and the transmittance and reflectance of the homogenizing device are adjusted by a thermochromic layer. The filtered light is then conducted to the sawtooth grating array through an intermediate medium. The sawtooth grating array is used to deflect the incident natural light into the indoor space after refraction through the inclined surface. Both the convex freeform surface array and the sawtooth grating array include n unit structures, which are one-to-one corresponding, where n is a natural number greater than or equal to 1.

[0302] More specifically: the two arrayed surfaces modulate different phases of the incident light. Specifically, the first convex freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent lens focal length in the first convex freeform surface array, λ is the center wavelength of natural light, and θ1 is the incident angle of the incident light on the first convex freeform surface; the second sawtooth grating array surface adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y2 is the position of the incident wavefront of the sawtooth surface array, and θ2 is the incident light angle.

[0303] More specifically: the expression for the thickness d1 at different positions (x1, y1) on the first convex freeform surface is as follows: r1 is the radius of curvature of the surface, α1 is the inclination angle of the first convex freeform surface, and the surface shape can be spherical, parabolic, or other forms. The radius of curvature is 1-5 times the minimum distance between the lens array and the freeform surface array. The expression for the thickness d at different positions (x2, y2) on a single structural unit of the sawtooth surface array is as follows: θ is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, which causes light to propagate horizontally through refraction.

[0304] More specifically: the front and rear surface arrays are square full-aperture arrays with a fill rate of over 95%, and the surface arrays of the two devices correspond one-to-one, with the center position of the surface matching the optical axis.

[0305] More specifically: The main components of the thermochromic coating are thermochromic powder (mainly methyl red, bisphenol, and melamine) and rutile titanium dioxide. The latter is used to prevent the coating from becoming transparent in a light-colored state and to increase the reflectivity of the coating at high temperatures. Macroscopically, the coating appears as a thin film with a thickness of less than 0.1 mm.

[0306] More specifically: In order to verify the effect of the above-mentioned device of the present invention, the first convex freeform surface array has a radius of curvature of r1 = 1 mm, a surface tilt angle of α1 = 10°, a sawtooth grating surface tilt angle of θ = 35°, the convex freeform surface array and the sawtooth grating array correspond one-to-one, the interval between the two planes is 1.5 mm, the array size is 1 mm * 1 mm, a 5 * 5 array is selected, and the material is ZF6 glass.

[0307] The aforementioned thermochromic natural light uniform illumination device, based on a composite multi-array structure, utilizes a sandwich structure of two uniform light substrates and a thermochromic coating. This structure allows natural light entering through windows during the day to be evenly distributed to every corner of the room, utilizing natural light for indoor illumination and reducing energy consumption caused by additional lighting in deep, sunny rooms. The thermochromic coating effectively blocks excessive sunlight from entering the room by regulating light entry, thus reducing glare and heat radiation intake. It features rapid color change and restoration of brightness, and its performance shows no fatigue degradation even after repeated darkening and fading, making it promising for practical applications. The use of different surface combinations breaks the symmetry of light transmission, effectively protecting indoor privacy. Furthermore, the free combination of the uniform light substrate and the thermochromic coating reduces manufacturing complexity; the single-piece uniform light substrate is thin, lightweight, and easy to mass-produce, requiring no special materials, making it suitable for large-scale production and promotion. As a multifunctional new type of lighting device, the intelligent thermochromic natural light uniform illumination device can replace lighting curtains, indoor blinds, and window glass.

[0308] While the embodiments disclosed in this invention are as described above, their content is merely for the purpose of facilitating understanding of the technical solutions of this invention and is not intended to limit the invention. Any person skilled in the art to which this invention pertains may make any modifications and changes to the form and details of the implementation without departing from the core technical solutions disclosed in this invention; however, the scope of protection defined by this invention shall still be determined by the scope defined in the appended claims.

Claims

1. A multifunctional natural light homogenization lighting device, characterized in that, The device includes a first light-diffusing substrate (1), a second light-diffusing substrate (3), and a multifunctional layer (2) sandwiched between the two. The first light-diffusing substrate (1), which is in direct contact with the outdoors, is a single-plane, freeform surface array, or lens array. The second light-diffusing substrate (3), which is in direct contact with the indoor environment, is a freeform surface array, lens array, or sawtooth grating array. The first light-diffusing substrate (1) is used to collect outdoor high-angle natural light, which is then processed by the multifunctional layer (2) and transmitted to the second light-diffusing substrate (3). The second light-diffusing substrate (3) is used to deflect the incident natural light into the indoor space after refraction through an inclined surface. The array of freeform surfaces can be either convex or concave. The convex freeform surface refracts light in the horizontal direction. The expression for the thickness d1 at different positions (x1, y1) on the convex freeform surface is: Where n is the refractive index, r1 is the radius of curvature at the vertex of the convex freeform surface, θ1 is the surface tilt angle of the convex freeform surface, and light propagates horizontally through refraction. The radius of curvature is 1-5 times the minimum distance between the working surfaces of the two uniform light substrates. The expression for the thickness d2 at different positions (x2, y2) on the concave freeform surface is: Where n is the refractive index, r2 is the radius of curvature of the vertex of the concave freeform surface, θ2 is the surface tilt angle of the concave freeform surface, and the light propagates in the horizontal direction through refraction. The radius of curvature is 1-5 times the minimum distance between the working surfaces of the two uniform light substrates. The lens array uses either convex or concave lenses. The expression for the thickness z1 at different positions (x1, y1) on the convex lens is: r3 is the radius of the curved surface, which is 1-5 times the minimum distance between the working surfaces of the two uniform light substrates; the expression for the thickness z2 at different positions (x2, y2) on the concave lens is: r4 is the surface radius, which is 1-5 times the minimum distance between the working surfaces of the two uniform light substrates; The expression for the thickness t at different positions (x, y) on a single structural unit of the sawtooth grating array is as follows: θ3 is the angle between the two grating surfaces that form the sawtooth in the sawtooth grating, and its value ranges from 20° to 70°. For natural light homogenizing substrates of different surface shapes, the freeform surface array adds phase modulation to the incident light. It can be represented as (x1, y1) represents the position of the incident wavefront of the freeform surface array, f1 is the equivalent focal length of the lens in the freeform surface array, λ is the center wavelength of the natural light, and α1 is the incident angle of the natural light on the freeform surface; the lens array adds phase modulation to the incident light. It can be represented as (x2, y2) represents the position of the incident wavefront of the lens array, λ is the center wavelength of natural light, and f2 is the focal length of the lens; the sawtooth grating array adds phase modulation to the incident light. It can be represented as λ is the center wavelength of natural light, y3 is the position of the incident wavefront of the sawtooth surface array, and α3 is the incident angle of natural light on the sawtooth surface. The multifunctional layer (2) is a thermal infrared reflective layer. The first uniform light substrate (1) is used to collect outdoor high-angle natural light, and the infrared light and thermal radiation are filtered by the thermal infrared reflective layer and then conducted to the second uniform light substrate (3). The infrared heat reflective layer is a metal film or a doped semiconductor film. By maintaining high transmittance of visible light, the infrared heat reflective layer blocks the transmission of infrared light, thereby reducing heat exchange on both sides of the uniform light substrate. During the day when the temperature is high, it can reduce the transmission of solar energy through the windows into the room. Even under strong sunlight, the indoor temperature will not be too high, greatly reducing the burden on air conditioning. When the temperature is low, it can block the heat energy in the room from being conducted to the outside through the windows and reflect the far-infrared radiation in the room, thereby reducing the energy consumption of indoor heating equipment. Outdoor natural light is collected by the working plane of the first uniform light substrate (1) and transmitted to the thermal infrared reflective layer through the intermediate medium; When the outdoor temperature is higher than the indoor temperature, the thermal infrared reflective layer reflects and blocks most of the solar heat and infrared rays, achieving a heat insulation effect; when the outdoor temperature is lower than the indoor temperature, the thermal infrared reflective layer has poor thermal conductivity, blocking the conduction of heat and maintaining a stable indoor temperature. The light filtered by the thermal infrared reflective layer is deflected into the indoor space after passing through the second uniform light substrate (3), thus achieving uniform illumination of the incident light.

2. The apparatus according to claim 1, characterized in that: The multifunctional layer (2) is an ultraviolet shielding film layer. The first uniform light substrate (1) is used to collect outdoor high-angle natural light and filter most of the ultraviolet rays in the UVA (320-400nm) and UVB (280-320nm) bands through the ultraviolet shielding film layer, and then conducts them to the second uniform light substrate (3). The ultraviolet shielding film is either an inorganic or organic ultraviolet shielding film, which can absorb or reflect ultraviolet rays of different wavelengths in sunlight, thereby effectively blocking ultraviolet rays from entering the room and preventing harm to human health and indoor furnishings caused by ultraviolet radiation.

3. The apparatus according to claim 2, characterized in that: Outdoor natural light is collected by the working plane of the first uniform light substrate (1) and transmitted to the ultraviolet shielding film layer through the intermediate medium; The ultraviolet shielding film reflects and blocks most of the ultraviolet rays; The light filtered by the ultraviolet shielding film is deflected into the indoor space after passing through the second uniform light substrate (3), so as to achieve uniform illumination of the incident light.

4. The apparatus according to claim 1, characterized in that: The multifunctional layer (2) is a photochromic coating. The first uniform light substrate (1) is used to collect outdoor high-angle natural light and adjust the transmittance of the lighting device through the photochromic coating, and then conduct it to the second uniform light substrate (3). The photochromic coating is either an inorganic or organic photochromic coating. When exposed to strong ultraviolet light or sunlight, the photochromic coating absorbs light in the visible spectrum and automatically changes color. After the strong light exposure stops, it reversibly and automatically returns to its initial transparent state.

5. The apparatus according to claim 4, characterized in that: Outdoor natural light is collected by the working plane of the first uniform light substrate (1) and transmitted to the photochromic coating through an intermediate medium; When outdoor natural light is strong, the photochromic coating reflects and blocks most of the natural light; When outdoor natural light becomes weak, the photochromic coating restores high transmittance, maintaining stable indoor lighting conditions; The light filtered by the photochromic coating is deflected into the indoor space after passing through the second uniform light substrate (3), so as to achieve uniform illumination of the incident light.

6. The apparatus according to claim 1, characterized in that: The multifunctional layer (2) is a thermochromic coating. The first uniform light substrate (1) is used to collect outdoor high-angle natural light, and the reflectivity, transmittance and absorptivity of the lighting device are dynamically adjusted by the thermochromic coating, and then transmitted to the second uniform light substrate (3). The thermochromic coating is an inorganic reversible thermochromic coating or an organic reversible thermochromic coating. The thermochromic coating can intelligently adjust the color of the film layer according to different temperatures, thereby achieving different transmittance and reflectance.

7. The apparatus according to claim 6, characterized in that: Outdoor natural light is collected by the working plane of the first uniform light substrate (1) and transmitted to the thermochromic coating through the intermediate medium. Its optical properties of spectral reflectivity, transmittance and absorptivity are related to its surface temperature. As the surface temperature changes, the material presents different colors and its reflection and absorption of solar radiation are also different. At higher temperatures, the thermochromic coating appears light-colored, reflecting and blocking most of the solar heat and infrared rays, thus achieving a heat insulation effect; at lower temperatures, the thermochromic coating appears dark-colored, absorbing more solar radiation and reducing energy consumption for indoor insulation. The light filtered by the thermochromic coating is deflected into the indoor space after passing through the second uniform light substrate (3), thus achieving uniform illumination of the incident light.

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