A light scattering plate and its manufacturing method and lighting device

Abstract

The present invention relates to a light scattering plate and a manufacturing method thereof and an illumination device. The light scattering plate comprises a first transparent substrate, and is characterized in that: it also comprises a scattering layer, the scattering layer is arranged on the first surface of the first transparent substrate, a plurality of tiny oil droplets wrapped by a solidified photosensitive resin are arranged in the scattering layer, a thin wall composed of the photosensitive resin is arranged between adjacent tiny oil droplets, the thickness of the thin wall is less than 500nm, and a plurality of nano-scattering particles with Rayleigh scattering effect are dispersed in the thin wall. The present invention not only has a higher integration degree and a lower processing cost, but also can greatly increase the optical path of blue light scattering, thereby increasing the scattering efficiency of blue light.

Description

Technical Field

[0001] The present invention relates to the field of lighting technology, and in particular to a light scattering plate and a manufacturing method thereof, and a lighting device. Background Art

[0002] Rayleigh scattering is an optical phenomenon and a type of scattering. When the particle size is much smaller than the wavelength of visible light, the intensity of the scattered light in each direction is inversely proportional to the fourth power of the wavelength of the incident light, so it tends to scatter the blue light component in the light. Based on the principle of Rayleigh scattering, the atmosphere scatters sunlight to form a blue sky.

[0003] Rayleigh scattering plates use artificial light scattering structures. Current Rayleigh scattering plates are generally transparent plates with nano-scattering particles dispersed therein. Rayleigh scattering plates can be used to simulate the scattering of sunlight by the atmosphere. When used in lamps, they can simulate the blue sky effect of atmospheric scattering of sunlight on lamps, which can not only meet the indoor lighting needs, but also improve the indoor environment. However, the Rayleigh scattering effect of current Rayleigh scattering plates is quite weak, and its scattering intensity is low. In order to achieve a sufficient scattering rate, it is necessary to increase the thickness of the scattering plate or increase the density of the nano-scattering particles. However, increasing the thickness of the scattering plate (such as more than 1 cm) will consume a large amount of base material (such as transparent resin), increase weight and cost, and increase the density of the nano-scattering particles, which is very easy to cause the nano-scattering particles to agglomerate. Large-scale agglomeration of the nano-scattering particles will reduce the scattering performance and cause the scattering layer to have problems such as uneven scattering. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a light scattering plate and a manufacturing method thereof and a lighting device, which not only have a higher degree of integration and a lower processing cost, but also can greatly increase the optical path of blue light scattering, thereby increasing the scattering efficiency of blue light. The technical solution adopted is as follows:

[0005] A light scattering plate comprises a first transparent substrate, characterized in that it also comprises a scattering layer, the scattering layer is arranged on the first surface of the first transparent substrate, a plurality of tiny oil droplets wrapped by a solidified photosensitive resin are arranged in the scattering layer, a thin wall composed of the photosensitive resin is arranged between adjacent tiny oil droplets, the thickness of the thin wall is less than 500nm, and a plurality of nano-scattering particles with Rayleigh scattering effect are dispersed in the thin wall.

[0006] The first transparent substrate can be a transparent glass substrate or a plastic substrate, such as a transparent glass or plastic substrate with a thickness of 0.3 to 10 mm; the first transparent substrate can also be a plastic film, such as a PET or CPI (colorless polyimide) film with a thickness of more than 0.05 mm. In general applications, the first surface is generally defined with a scattering area, and the scattering layer is arranged in the scattering area.

[0007] In the above-mentioned light scattering plate, since the thickness of the thin wall is less than 500nm, for non-blue visible light with a longer wavelength (λ>500nm), the thickness of the thin wall is not enough to separate the near-field effect of the light wave between its two surfaces. Therefore, when the non-blue visible light passes through the thin wall, its refraction effect is not obvious, and it is manifested as direct penetration with very little scattering; while for blue light with a shorter wavelength (λ<500nm), the thickness of the thin wall is greater than the wavelength, which can separate the near-field effect of the light wave between its two surfaces, so that the blue light appears to be refracted at the interface on both sides of the thin wall, and because the thin wall is uneven, the blue light after refraction will initially be scattered, thereby increasing the optical path of the blue light within the scattering layer. Since there are multiple nano-scattering particles dispersed in the thin wall, the nano-scattering particles can produce Rayleigh scattering effect, so the blue light will be scattered under the action of the thin wall. After scattering, the angles of most of the light rays are no longer perpendicular to the first surface, and can experience multiple scattering, so its optical path is greatly increased. After the optical path is extended, the Rayleigh scattering effect of the nano-scattering particles on the blue light is greatly increased, which significantly increases the scattering efficiency of the blue light.

[0008] Generally, in order to generate sufficient Rayleigh scattering, as a preferred solution of the present invention, the thickness of the scattering layer is 20-500 μm. When the thickness of the scattering layer is less than 100 μm, the weight of the nano scattering particles is 2-5% of the photosensitive resin; when the thickness of the scattering layer is 100-200 μm, the weight of the nano scattering particles is 1-2.5% of the photosensitive resin; when the thickness of the scattering layer is 200-500 μm, the weight of the nano scattering particles is 0.5-1.5% of the photosensitive resin.

[0009] As a preferred solution of the present invention, the photosensitive resin is a transparent photosensitive resin. Specifically, the transparent photosensitive resin is an acrylic resin added with a photoinitiator.

[0010] As a preferred solution of the present invention, the micro oil droplets are droplets of oil that is difficult to fuse with the photosensitive resin, specifically, droplets of mineral oil, olefin compounds or silicone oil.

[0011] As a preferred solution of the present invention, the thin wall has a first refractive index, and the tiny oil droplet has a second refractive index that is not equal to the first refractive index.

[0012] As a preferred solution of the present invention, the nano-scattering particles are inorganic nano-particles with a size of 5-40 nm, so that the size of the inorganic nano-particles can be much smaller than the thickness of the thin wall, and thus they will not affect the structure of the thin wall.

[0013] As a further preferred embodiment of the present invention, the inorganic nanoparticles are composed of at least one of nano-aluminum dioxide, nano-silicon dioxide, nano-molybdenum disulfide, nano-titanium dioxide, nano-zinc oxide, or a mixture thereof.

[0014] As a preferred embodiment of the present invention, the thickness of the thin wall is 200-500 nm.

[0015] As a preferred embodiment of the present invention, the size of the micro oil droplets is 1 to 10 μm.

[0016] As a further preferred embodiment of the present invention, the size of the micro-oil droplets is 1 to 4 μm. The smaller the size of the micro-oil droplets, the higher density of thin walls they can form. When the size of the micro-oil droplets is above 1 μm, the distance between adjacent thin walls can be greater than the wavelength of visible light, thereby preventing light waves from forming a near-field effect between thin walls.

[0017] In order to make the light scattering plate have an electric control function and meet the needs of more usage scenarios, as a preferred solution of the present invention, a first transparent electrode and a second transparent electrode are respectively provided on both sides of the scattering layer; and the tiny oil droplets are liquid crystal droplets.

[0018] The liquid crystal is generally a positive nematic liquid crystal with optical anisotropy. Generally, although the nematic liquid crystal has a certain order in molecular orientation, its overall form is still an oily liquid, and the liquid crystal should be considered as oil here. Since the nematic liquid crystal has birefringence, it has two refractive indices n1 and n2. When the tiny oil droplets are liquid crystal droplets, the second refractive index refers to any value within the liquid crystal birefringence interval [n1, n2], and the first refractive index is a value outside the birefringence interval [n1, n2].

[0019] The first transparent electrode and the second transparent electrode can be directly connected to the mains voltage.

[0020] The above-mentioned light scattering plate with electric control function can work in a first scattering state and a second scattering state: when no voltage is applied to the first transparent electrode and the second transparent electrode (or a smaller voltage that does not exceed the threshold is applied), the scattering layer works in the first scattering state; in the first scattering state, the liquid crystal molecules of different liquid crystal droplets are randomly oriented, and the liquid crystals on both sides of the thin wall have a refractive index difference due to different orientations. The full-wavelength visible light shows strong light refraction between the liquid crystal droplets, so that the entire scattering layer scatters the full-wavelength visible light, and the scattering layer appears milky white. When light (white light or simulated sunlight) irradiates the above-mentioned light scattering plate, its light is soft white scattered light, similar to the lighting effect of fluorescent lamps and other lamps. When the first transparent electrode and the second transparent electrode apply voltage (exceeding the threshold voltage), the scattering layer works in the second scattering state; in the second scattering state, the liquid crystal molecules of different liquid crystal droplets are affected by the electric field between the first transparent electrode and the second transparent electrode, and they are deflected along the electric field lines and present a consistent orientation. The liquid crystals on both sides of the thin wall have the same orientation and the same refractive index. The action of the liquid crystal droplets is similar to that of ordinary oil, and its optical action is restored to the principle described above. The scattering layer mainly presents Rayleigh scattering, which can scatter blue light more efficiently while keeping other bands of visible light non-scattered. This light scattering plate can achieve switching control between the first scattering state and the second scattering state through only one scattering layer: in the first scattering state, the scattering layer can scatter the full-band visible light, and the scattering structure presents milky white, which is not only soft in color but also presents a lighting effect similar to fluorescent lamps under the irradiation of the light source, which is suitable for night lighting; in the second scattering state, the scattering layer presents blue light scattering, which can be used to simulate the effect of blue sky and sunlight on a sunny day.

[0021] As a further preferred embodiment of the present invention, the first transparent electrode and the second transparent electrode are made of a first transparent conductive film and a second transparent conductive film respectively; the first transparent conductive film is arranged on the first surface of the first transparent substrate, and the second transparent conductive film is arranged on the scattering layer. The first transparent conductive film and the second transparent conductive film can be transparent conductive oxide films (such as ITO films), transparent conductive polymer coatings (such as PEDOT:PSS coatings) or nano silver wire transparent conductive films and other transparent conductive film layers, and the first transparent electrode and the second transparent electrode can be made by plating, coating, printing and other methods; during the production, the first transparent conductive film can be an ITO film pre-plated on the first surface of the first transparent substrate, and the second transparent conductive film can be directly plated on the scattering layer.

[0022] As another further preferred embodiment of the present invention, the first transparent electrode and the second transparent electrode are made of a first transparent conductive film and a second transparent conductive film respectively; the first transparent conductive film is arranged on the first surface of the first transparent substrate; the light scattering plate also includes a second transparent substrate, the second transparent substrate is attached to the second surface of the first transparent substrate, and the second transparent conductive film is arranged on the second transparent substrate. The first transparent conductive film and the second transparent conductive film can be transparent conductive oxide films (such as ITO films), transparent conductive polymer coatings (such as PEDOT:PSS coatings) or nano silver wire transparent conductive films and other transparent conductive film layers, and the first transparent electrode and the second transparent electrode can be made by plating, coating, printing and other methods; during the production, the second transparent conductive film can be pre-arranged on the second transparent substrate (such as a transparent glass substrate, a plastic substrate or a plastic film), and the second transparent substrate is attached to the first transparent substrate, so that the second transparent conductive film is on the other side of the scattering layer.

[0023] As a preferred solution of the present invention, a transparent protective layer is provided on one side of the scattering layer away from the first transparent substrate. The transparent protective layer can be a transparent plastic film such as PET, CPI, PVC, acrylic, etc., which can protect the scattering layer.

[0024] The present invention also provides a method for manufacturing a light scattering plate, which is characterized by comprising the following steps:

[0025] S1, firstly mixing a plurality of nano-scattering particles in an uncured photosensitive resin, so that the surface of each nano-scattering particle is infiltrated in the photosensitive resin;

[0026] S2, adding oil, and fully mixing the oil and the photosensitive resin by ultrasonic emulsification to form tiny oil droplets, thereby forming a mixed emulsion of the oil and the photosensitive resin;

[0027] S3, providing a first transparent substrate, and coating the mixed emulsion on a first surface of the first transparent substrate;

[0028] S4, irradiating ultraviolet light to solidify the photosensitive resin in the mixed emulsion to form a scattering layer, wherein a plurality of tiny oil droplets wrapped by the solidified photosensitive resin are arranged in the scattering layer, a thin wall formed by the photosensitive resin is arranged between adjacent tiny oil droplets, the thickness of the thin wall is less than 500nm, and a plurality of nano-scattering particles with Rayleigh scattering effect are dispersed in the thin wall.

[0029] In the above manufacturing method, in step S1, the nano-scattering particles are inorganic nano-particles with a size of 5 to 40 nm, which can be composed of at least one of nano-aluminum dioxide, nano-silicon dioxide, nano-molybdenum disulfide, nano-titanium dioxide, and nano-zinc oxide, or a mixture of at least two of them; in step S2, the ultrasonic wave can not only break up the nano-scattering particles to prevent them from agglomerating, but also its emulsification effect can make the oil and the photosensitive resin fully mixed to form tiny oil droplets, which can play a role in separating and dispersing the scattering particles, so that the scattering particles are not easy to agglomerate; in step S3, the first transparent substrate can be a transparent glass substrate, a plastic substrate, such as a transparent substrate with a thickness of 0.3 to 10 The transparent glass or plastic substrate of mm can also be a plastic film, such as PET, CPI (colorless polyimide) film with a thickness of more than 0.05mm; in the step S4, since a plurality of nano scattering particles are dispersed in the thin wall, the nano scattering particles can produce Rayleigh scattering, so the blue light will be scattered under the action of the thin wall, and after scattering, the angle of most of its light rays is no longer perpendicular to the first surface, and it can experience multiple scattering, so its optical path is greatly increased. After the optical path is extended, the Rayleigh scattering effect of the nano scattering particles on the blue light is greatly increased, which significantly increases the scattering efficiency of the blue light. This manufacturing method can scatter blue light more efficiently while keeping other bands of visible light non-scattered, while avoiding the agglomeration of scattering particles when manufacturing the scattering layer, and improving its quality.

[0030] The first transparent conductive film and the second transparent conductive film can be transparent conductive oxide films (such as ITO films), transparent conductive polymer coatings (such as PEDOT:PSS coatings) or nano silver wire transparent conductive films and other transparent conductive film layers. The first transparent electrode and the second transparent electrode can be manufactured by plating, coating, printing and other methods.

[0031] As a preferred embodiment of the present invention, some of the micro-oil droplets are evenly and densely distributed on the plane of the scattering layer (i.e., the surface parallel to the first surface of the first transparent substrate). More preferably, at any position of the scattering layer, there are multiple micro-oil droplets overlapping in a direction perpendicular to the plane of the scattering layer. Generally, under the condition of sufficient mixing, the thickness of the thin wall can be adjusted according to the ratio of the photosensitive resin to the oil. For example, if the ratio of the photosensitive resin to the oil is less than 1:10, the thickness of the thin wall can be easily made less than 500nm, especially 400-500nm. Generally, after completing step (2), steps (3) and (4) are immediately performed, and the above structure can be quickly fixed to avoid the merging of the micro-oil droplets, and to ensure the thickness of the thin wall and the non-agglomeration of the nano-scattering particles.

[0032] Generally, in order to improve the color, a blue dye, such as anthraquinone dye, may be added to the scattering layer. As a preferred embodiment of the present invention, the photosensitive resin or the tiny oil droplets are mixed with a blue dye, and the weight of the blue dye does not exceed 20% of the total weight of the nano scattering particles.

[0033] In order to make the above-mentioned light scattering plate have an electrical control function and meet the needs of more usage scenarios, as a preferred solution of the present invention, in the step S2, the tiny oil droplets are liquid crystal droplets; in the step S3, a first transparent electrode made of a first transparent conductive film is first arranged on the first surface of the first transparent substrate, and then the mixed emulsion is applied to the first surface of the first transparent substrate and the first transparent electrode; in the step S4, after the scattering layer is formed, a second transparent electrode made of a second transparent conductive film is arranged on the side of the scattering layer away from the first transparent substrate.

[0034] The liquid crystal is generally a positive nematic liquid crystal with optical anisotropy. Generally, although the positive nematic liquid crystal has a certain order in molecular orientation, its overall form is still an oily liquid, and the liquid crystal should be considered as oil here. Since the nematic liquid crystal has birefringence, it has two refractive indices n1 and n2. When the tiny oil droplets are liquid crystal droplets, the second refractive index refers to any value within the liquid crystal birefringence interval [n1, n2], and the first refractive index is a value outside the birefringence interval [n1, n2].

[0035] As a further preferred embodiment of the present invention, in step S3, the first transparent conductive film is pre-plated on the first surface of the first transparent substrate; in step S4, the second transparent conductive film is directly plated on the side of the scattering layer away from the first transparent substrate.

[0036] As another further preferred embodiment of the present invention, in step S3, the first transparent conductive film is pre-plated on the first surface of the first transparent substrate; in step S4, a second transparent substrate is provided, the second transparent conductive film is pre-disposed on the second transparent substrate, and the second transparent substrate is then bonded to the first transparent substrate so that the second transparent conductive film is on the other side of the scattering layer.

[0037] The present invention further provides a lighting device, comprising a light-emitting component, characterized in that it also comprises the light scattering plate, and the light scattering plate is arranged on the front side of the light-emitting component.

[0038] The lighting device can be suitable for installation on an indoor ceiling as a planar lamp.

[0039] When the lighting device is working, most of the light emitted by the light emitting component is emitted through the light scattering plate to form lighting. When non-blue visible light with a longer wavelength (λ>500nm) passes through the thin wall, its refraction effect is not obvious, and it is manifested as direct penetration with very little scattering. The blue light with a shorter wavelength (λ<500nm) is refracted at the interface on both sides of the thin wall. Since the thin wall is uneven, the blue light after refraction will initially scatter, which can increase the optical path of the blue light in the scattering layer. Moreover, since a plurality of nano scattering particles are dispersed in the thin wall, the nano scattering particles can produce Rayleigh scattering, so the blue light will be scattered under the action of the thin wall. After scattering, the angles of most of its light rays are no longer perpendicular to the first surface, and it can experience multiple scatterings, so its optical path is greatly increased. After the optical path is extended, the Rayleigh scattering effect of the nano scattering particles on the blue light is greatly increased, which significantly increases the scattering efficiency of the blue light. Therefore, the blue sky effect of atmospheric scattered sunlight is simulated at the light outlet, which can not only meet the indoor lighting needs, but also improve the indoor environmental atmosphere.

[0040] The light-emitting component may include a lighting element, and the lighting element may use a lighting LED (such as a white light LED) or other lighting elements (such as a fluorescent lamp, an incandescent lamp) to realize light emission when powered on. These lighting elements may be equipped with lenses, such as a focusing lens corresponding to the LED, in order to gather the scattered light and make it shine toward the light-transmitting plate, for example: to make the light shine obliquely toward the light-transmitting plate and form illumination through the light-transmitting plate. The light-emitting component may have either a fixed light-emitting color or an adjustable light-emitting color. For example: the lighting element may be provided with two or more LEDs of different colors, such as a warm-colored LED and a cool-colored LED. By adjusting the light-dark ratio of these LEDs, the light-emitting component can simulate different light colors, such as simulating light in the morning, noon or evening.

[0041] The light-emitting component generally also includes a fixed structure and a lighting driver module. The fixed structure can be a PCB board for fixing LEDs. The lighting driver module generally has a basic transformer and rectifier function, which can provide the required voltage or current for lighting elements such as LEDs. In some simple implementation schemes, the lighting driver module can directly output the required voltage or current for the lighting element according to the power-on of the lighting device (such as controlled by an indoor switch); and in some complex implementation schemes, the lighting driver module can also have a timing adjustment function, a remote control receiving function or a wireless (such as Bluetooth, wifi) receiving function, which allows the user to control the luminous brightness of the lighting element by timing, remote control or wireless, especially for the variable color scheme, the lighting driver module can also have a color adjustment function, for example: it can output corresponding currents for LEDs of different colors to change the color. In order to improve the stability and durability of the light source, the light-emitting component can also be provided with a heat dissipation structure, such as a heat sink connected to the fixed structure or even a heat dissipation fan.

[0042] In the case where the above-mentioned light scattering plate has an electrical control function (i.e., a first transparent electrode and a second transparent electrode are respectively provided on both sides of the scattering layer, and the tiny oil droplets are liquid crystal droplets), the voltage applied to the first transparent electrode and the second transparent electrode can be directly provided by the lighting driving module, so that when the lighting device is powered off, the scattering layer is naturally in a milky white state, and when the lighting device is powered on, the liquid crystal layer is switched to a transparent state.

[0043] As a preferred solution of the present invention, the lighting device also includes a light box, a light outlet is provided at the front end of the light box, the light scattering plate is provided at the light outlet, and the light emitting component is installed in the light box and is located at the rear side of the light scattering plate.

[0044] Compared with the prior art, the present invention has the following advantages:

[0045] (1) The light scattering plate of the present invention has a higher degree of integration and a lower processing cost. In addition, since a plurality of nano-scattering particles are dispersed in the thin wall, the nano-scattering particles can produce Rayleigh scattering. Therefore, the blue light will be scattered under the action of the thin wall. After scattering, the angles of most of the light rays are no longer perpendicular to the first surface and can undergo multiple scattering. Therefore, the optical path is greatly increased. After the optical path is extended, the Rayleigh scattering effect of the nano-scattering particles on the blue light is greatly increased, which significantly increases the scattering efficiency of the blue light.

[0046] (2) The present invention can achieve switching control between a first scattering state and a second scattering state by only using one scattering layer: in the first scattering state, the scattering layer can scatter visible light of the entire wavelength band, and the scattering structure appears milky white, which not only has a soft color but also presents a lighting effect similar to that of fluorescent lamps under the illumination of a light source, and is suitable for nighttime lighting; in the second scattering state, the scattering layer scatters blue light, which can be used to simulate the effect of blue sky and sunlight on a sunny day. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] Figure 1 It is a structural schematic diagram of a light scattering plate provided in a preferred embodiment 1 of the present invention.

[0048] Figure 2 yes Figure 1 Schematic diagram of the structure of the scattering layer in the light scattering plate shown.

[0049] Figure 3 It's the light passing through Figure 2 Schematic diagram of the optical principle when the scattering layer is shown.

[0050] Figure 4 It is a structural schematic diagram of a lighting device provided in a preferred embodiment 1 of the present invention.

[0051] Figure 5 It is a structural schematic diagram of a light scattering plate provided in the second preferred embodiment of the present invention.

[0052] Figure 6 yes Figure 5 The diagram is a schematic diagram of the state of the scattering layer of the light scattering plate when it operates in the first scattering state.

[0053] Figure 7 yes Figure 5 The diagram is a schematic diagram of the state of the scattering layer of the light scattering plate when it operates in the second scattering state.

[0054] Figure 8 It is a structural schematic diagram of a lighting device provided in a second preferred embodiment of the present invention. DETAILED DESCRIPTION

[0055] Embodiment 1.

[0056] like Figure 1-Figure 4 As shown, the light scattering plate 10 includes a first transparent substrate 11 and a scattering layer 12. The scattering layer 12 is arranged on the first surface 111 of the first transparent substrate 11. A plurality of tiny oil droplets 121 wrapped by a cured photosensitive resin 1220 are arranged in the scattering layer 12. A thin wall 122 composed of the photosensitive resin 1220 is arranged between adjacent tiny oil droplets 121. The thickness of the thin wall 122 is less than 500 nm. A plurality of nano-scattering particles 1221 with Rayleigh scattering effect are dispersed in the thin wall 122.

[0057] In this embodiment, the first transparent substrate 11 is a transparent glass substrate or a transparent plastic substrate with a thickness of 0.3-10 mm; the first surface 111 of the first transparent substrate 11 defines a scattering region, and the scattering layer 12 is disposed in the scattering region.

[0058] In order to generate sufficient Rayleigh scattering, in this embodiment, the thickness of the scattering layer 12 is 20-500 μm. When the thickness of the scattering layer 12 is less than 100 μm, the weight of the nano scattering particles 1221 is 2-5% of the photosensitive resin 1220; when the thickness of the scattering layer 12 is 100-200 μm, the weight of the nano scattering particles 1221 is 1-2.5% of the photosensitive resin 1220; when the thickness of the scattering layer 12 is 200-500 μm, the weight of the nano scattering particles 1221 is 0.5-1.5% of the photosensitive resin 1220.

[0059] In this embodiment, the photosensitive resin 1220 is a transparent photosensitive resin, such as acrylic resin with a photoinitiator added.

[0060] In this embodiment, the tiny oil droplets 121 are made of oil droplets that are difficult to fuse with the photosensitive resin 1220, such as droplets of mineral oil, olefin compounds, or silicone oil.

[0061] In this embodiment, the thin wall 122 has a first refractive index, and the tiny oil droplet 121 has a second refractive index that is not equal to the first refractive index.

[0062] In this embodiment, the nano-scattering particles 1221 are inorganic nano-particles with a size of 5 to 40 nm, which are composed of at least one of nano-aluminum dioxide, nano-silicon dioxide, nano-molybdenum disulfide, nano-titanium dioxide, and nano-zinc oxide, or a mixture thereof. Thus, the size of the inorganic nano-particles can be much smaller than the thickness of the thin wall 122, so that they will not affect the structure of the thin wall 122.

[0063] In this embodiment, the thickness of the thin wall 122 is 200-500 nm.

[0064] In this embodiment, the size of the tiny oil droplet 121 is 1-4 μm. The smaller the size of the tiny oil droplet 121, the higher density of thin walls 122 can be formed. When the size of the tiny oil droplet 121 is greater than 1 μm, the distance between adjacent thin walls 122 can be greater than the wavelength of visible light, thereby preventing the light wave from forming a near-field effect between the thin walls 122.

[0065] In this embodiment, a transparent protective layer 13 is disposed on one side of the scattering layer 12 away from the first transparent substrate 11. The transparent protective layer 13 can be a transparent plastic film such as PET, CPI, PVC, acrylic, etc., which can protect the scattering layer 12.

[0066] In the light scattering plate 10, since the thickness of the thin wall 122 is less than 500nm, for non-blue visible light 100 with a longer wavelength (λ>500nm), the thickness of the thin wall 122 is not enough to separate the near-field effect of the light wave between its two surfaces. Therefore, when the non-blue visible light 100 passes through the thin wall 122, its refraction effect is not obvious, and it is manifested as direct penetration with very little scattering; while for blue light 200 with a shorter wavelength (λ<500nm), the thickness of the thin wall 122 is greater than the wavelength, which can separate the near-field effect of the light wave between its two surfaces, so that the blue light 200 is refracted at the interface on both sides of the thin wall 122, and because the thin wall 122 is uneven, the blue light 200 after refraction will initially be scattered, thereby increasing the optical path of the blue light 200 in the scattering layer 12. Since a plurality of nano-scattering particles 1221 are dispersed within the thin wall 122, the nano-scattering particles 1221 can produce Rayleigh scattering, so the blue light 200 will be scattered under the action of the thin wall 122, and the angles of most of the light rays after scattering are no longer perpendicular to the first surface 111, and the light rays can undergo multiple scatterings, so that the optical path is greatly increased. After the optical path is extended, the Rayleigh scattering effect of the nano-scattering particles 1221 on the blue light 200 is greatly increased, and the scattering efficiency of the blue light 200 is significantly increased.

[0067] This embodiment also provides a method for manufacturing the light scattering plate 10, comprising the following steps:

[0068] S1, firstly mixing a plurality of nano-scattering particles 1221 in an uncured photosensitive resin 1220, so that the surface of each nano-scattering particle 1221 is infiltrated in the photosensitive resin 1220;

[0069] S2, adding oil, and fully mixing the oil and the photosensitive resin 1220 by ultrasonic emulsification to form tiny oil droplets 121, thereby forming a mixed emulsion of the oil and the photosensitive resin 1220;

[0070] S3, providing a first transparent substrate 11, and coating the mixed emulsion on the first surface 111 of the first transparent substrate 11;

[0071] S4. Irradiate ultraviolet light to solidify the photosensitive resin 1220 in the mixed emulsion to form a scattering layer 12. The scattering layer 12 is provided with a plurality of tiny oil droplets 121 wrapped by the solidified photosensitive resin 1220. A thin wall 122 formed by the photosensitive resin 1220 is provided between adjacent tiny oil droplets 121. The thickness of the thin wall 122 is less than 500 nm. A plurality of nano-scattering particles 1221 with Rayleigh scattering effect are dispersed in the thin wall 122.

[0072] In this embodiment, some of the tiny oil droplets 121 are evenly and densely distributed on the plane of the scattering layer 12 (i.e., the surface parallel to the first surface 111 of the first transparent substrate 11); at any position of the scattering layer 12, there are multiple overlapping tiny oil droplets 121 in the direction perpendicular to the plane of the scattering layer 12. Under the condition of full mixing, the thickness of the thin wall 122 can be adjusted according to the ratio of the photosensitive resin 1220 to the oil. For example, if the ratio of the photosensitive resin 1220 to the oil is less than 1:10, it is easy to make the thickness of the thin wall 122 less than 500nm, especially 400-500nm. After completing step (2), steps (3) and (4) are immediately performed to quickly fix the structure to avoid the merging of the tiny oil droplets 121, and ensure the thickness of the thin wall 122 and the non-agglomeration of the nano scattering particles 1221.

[0073] To improve the color, blue dyes, such as anthraquinone dyes, may be added to the scattering layer 12. In this embodiment, the photosensitive resin 1220 or the tiny oil droplets 121 are mixed with blue dyes, and the weight of the blue dyes does not exceed 20% of the total weight of the nano scattering particles 1221.

[0074] In this embodiment, in step S3 , the first transparent conductive film 30 is pre-plated on the first surface 111 of the first transparent substrate 11 ; in step S4 , the second transparent conductive film 40 is directly plated on the side of the scattering layer 12 away from the first transparent substrate 11 .

[0075] In this embodiment, in step S3, the first transparent conductive film 30 is pre-plated on the first surface 111 of the first transparent substrate 11; in step S4, a second transparent substrate is provided, and the second transparent conductive film 40 is pre-disposed on the second transparent substrate, and then the second transparent substrate is laminated to the first transparent substrate 11 so that the second transparent conductive film 40 is located on the other side of the scattering layer 12.

[0076] The lighting device provided in this embodiment includes a light scattering plate 10, a light emitting component 20 and a light box 30. A light outlet 301 is provided at the front end of the light box 30. The light scattering plate 10 is arranged at the light outlet 301. The light emitting component 20 is installed in the light box 30 and is located at the rear side of the light scattering plate 10.

[0077] In this embodiment, the light-emitting component 20 includes a lighting element 210 and a fixed structure 220. The lighting element 210 uses a lighting LED (such as a white light LED) or other lighting elements 210 (such as a fluorescent lamp, an incandescent lamp) to realize power-on lighting. These lighting elements 210 can be equipped with a lens, such as a focusing lens corresponding to the LED, which is intended to gather the scattered light and make it shine toward the light-transmitting plate, for example: make the light shine obliquely toward the light-transmitting plate and form illumination through the light-transmitting plate. The light-emitting component 20 can be either a fixed light-emitting color or an adjustable light-emitting color. For example: the lighting element 210 can be provided with two or more LEDs of different colors, such as a warm color LED and a cold color LED. By adjusting the light and dark ratio of these LEDs, the light-emitting component 20 can simulate different light colors, such as simulating the light in the morning, noon or evening. The fixed structure 220 can use a PCB board for fixing LEDs.

[0078] The following is a brief description of the working principle of this lighting device:

[0079] The lighting device can be suitable for being installed on an indoor ceiling as a planar lamp.

[0080] During operation, most of the light emitted by the light emitting component 20 is emitted through the light scattering plate 10 to form illumination. When the non-blue visible light 100 with a longer wavelength (λ>500nm) passes through the thin wall 122, its refraction effect is not obvious, and it is directly penetrated with very little scattering. The blue light 200 with a shorter wavelength (λ<500nm) is refracted at the interface on both sides of the thin wall 122. Since the thin wall 122 is not flat, the blue light 200 after refraction will be initially scattered, which can increase the optical path of the blue light 200 in the scattering layer 12. In addition, since a plurality of nano-scattering particles are dispersed in the thin wall 122, the blue light 200 can be directly penetrated by the thin wall 122. The nano scattering particles 1221 can produce Rayleigh scattering effect, so the blue light 200 will be scattered under the action of the thin wall 122. After scattering, the angles of most of the light rays are no longer perpendicular to the first surface 111, and multiple scatterings can be experienced, so that the optical path is greatly increased. After the optical path is extended, the Rayleigh scattering effect of the nano scattering particles 1221 on the blue light 200 is greatly increased, and the scattering efficiency of the blue light 200 is significantly increased, thereby simulating the blue sky effect of atmospheric scattered sunlight at the light outlet 301, which can not only meet the indoor lighting needs, but also improve the indoor environmental atmosphere.

[0081] Embodiment 2.

[0082] refer to Figure 5-Figure 8 , when other parts are the same as those in the first embodiment, the difference is that: in order to make the light scattering plate 10 have an electric control function and meet the needs of more usage scenarios, a first transparent electrode 14 and a second transparent electrode 15 are respectively provided on both sides of the scattering layer 12, and the tiny oil droplets 121 are liquid crystal droplets. The liquid crystal is a positive nematic liquid crystal with optical anisotropy. Although the positive nematic liquid crystal has a certain order in molecular orientation, its overall form is still an oily liquid. The liquid crystal should be considered as oil here. Since the nematic liquid crystal has birefringence, it has two refractive indices n1 and n2. When the tiny oil droplets 121 are liquid crystal droplets, the second refractive index refers to any value within the liquid crystal birefringence interval [n1, n2], and the first refractive index is a value outside the birefringence interval [n1, n2].

[0083] In this embodiment, the first transparent electrode 14 and the second transparent electrode 15 are respectively made of a first transparent conductive film 30 and a second transparent conductive film 40; the first transparent conductive film 30 is pre-plated on the first surface 111 of the first transparent substrate 11, and the second transparent conductive film 40 is directly plated on the scattering layer 12.

[0084] In this embodiment, the first transparent electrode 14 and the second transparent electrode 15 can be directly connected to the mains voltage.

[0085] In the manufacturing method of the light scattering plate 10 provided in this embodiment, in step S2, the tiny oil droplets 121 are liquid crystal droplets; in step S3, the first transparent electrode 14 made of the first transparent conductive film 30 is firstly arranged on the first surface 111 of the first transparent substrate 11, and then the mixed emulsion is coated on the first surface 111 of the first transparent substrate 11 and the first transparent electrode 14; in step S4, after the scattering layer 12 is formed, the second transparent electrode 15 made of the second transparent conductive film 40 is arranged on the side of the scattering layer 12 away from the first transparent substrate 11.

[0086] In this embodiment, the light scattering plate 10 is fixed at the light outlet 301 of the light box 30 through the shell structure 300 of the light box 30; the lighting device also includes a driving module 40, which has a basic transformer and rectifier function, and can provide the required voltage or current for the lighting element 210 such as LED, and the driving module 40 can also provide the light scattering plate 10 with a driving signal for switching between the first scattering state and the second scattering state. For example, a 5-30V DC, AC or square wave driving signal is taken from the driving module, so that the liquid crystal driving module 40 and the lighting driving module can achieve a common on / off control logic, so that when the lighting device is powered off, the liquid crystal layer is in a milky state, and when the lighting device is powered on, the liquid crystal driving module 40 is activated and outputs a driving signal, so that the liquid crystal layer is in a transparent state.

[0087] The following is a brief description of the working principle of this lighting device:

[0088] When working, most of the light emitted by the light-emitting component 20 is emitted through the light scattering plate 10 to form illumination; the light scattering plate 10 can work in a first scattering state and a second scattering state: when the first transparent electrode 14 and the second transparent electrode 15 are not applied with voltage (or a smaller voltage that does not exceed the threshold is applied), the scattering layer 12 works in the first scattering state; in the first scattering state, the liquid crystal molecules 1211 of different liquid crystal droplets are randomly oriented, and the liquid crystals on both sides of the thin wall 122 have a refractive index difference due to different orientations. The full-wavelength visible light shows strong light refraction between the liquid crystal droplets, so that the entire scattering layer 12 scatters the full-wavelength visible light, and the scattering layer 12 appears milky white. When light (white light or simulated sunlight) irradiates the light scattering plate 10, its light appears as soft white scattered light, similar to the lighting effect of fluorescent lamps and other lamps. When the first transparent electrode 14 and the second transparent electrode 15 apply a voltage (exceeding the threshold voltage), the scattering layer 12 works in the second scattering state; in the second scattering state, the liquid crystal molecules 1211 of different liquid crystal droplets are affected by the electric field between the first transparent electrode 14 and the second transparent electrode 15, and they are deflected along the electric field lines and present a consistent orientation, and the liquid crystals on both sides of the thin wall 122 have the same orientation and the same refractive index. The action of the liquid crystal droplets is similar to that of ordinary oil, and its optical action is restored to the above principle. The scattering layer 12 mainly presents Rayleigh scattering, which can more efficiently scatter blue light 200 while keeping visible light in other bands non-scattered. This light scattering plate 10 can achieve switching control between a first scattering state and a second scattering state through only one scattering layer 12: in the first scattering state, the scattering layer 12 can scatter the entire band of visible light, and the scattering structure appears milky white, which is not only soft in color but also presents a lighting effect similar to that of fluorescent lamps under the illumination of a light source, and is suitable for night lighting; in the second scattering state, the scattering layer 12 scatters blue light 200, which can be used to simulate the effect of blue sky and sunlight on a sunny day.

[0089] In addition, it should be noted that the names of the various parts of the specific embodiments described in this specification may be different, and any equivalent or simple changes made based on the structure, features and principles of the patent concept of the present invention are included in the protection scope of the patent of the present invention. Those skilled in the art of the present invention can make various modifications or supplements to the specific embodiments described or replace them in a similar manner, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A light scattering plate for a lighting device, comprising a first transparent substrate, characterized in that: The invention also includes a scattering layer, which is arranged on the first surface of the first transparent substrate, has a thickness of 20 to 500 μm, has a plurality of tiny oil droplets wrapped by a cured photosensitive resin, has a size of 1 to 4 μm, has a thin wall composed of the photosensitive resin between adjacent tiny oil droplets, has a thickness of 200 to 500 nm, has a first refractive index, has a second refractive index that is not equal to the first refractive index, has a plurality of nano-scattering particles with Rayleigh scattering effect dispersed in the thin wall, and has an inorganic nano-particle size of 5 to 40 nm.

2. A light scattering plate for a lighting device according to claim 1, characterized in that: The photosensitive resin is a transparent photosensitive resin.

3. The light scattering plate for a lighting device according to claim 1, characterized in that: The minute oil droplets are oil droplets that are difficult to fuse with the photosensitive resin.

4. The light scattering plate for a lighting device according to claim 1, characterized in that: The inorganic nanoparticles are composed of at least one of nano-aluminum dioxide, nano-silicon dioxide, nano-molybdenum disulfide, nano-titanium dioxide, nano-zinc oxide, or a mixture thereof.

5. The light scattering plate for a lighting device according to claim 1, characterized in that: A first transparent electrode and a second transparent electrode are respectively disposed on both sides of the scattering layer; and the tiny oil droplets are liquid crystal droplets.

6. The light scattering plate for a lighting device according to claim 5, characterized in that: The first transparent electrode and the second transparent electrode are made of a first transparent conductive film and a second transparent conductive film respectively; the first transparent conductive film is arranged on the first surface of the first transparent substrate, and the second transparent conductive film is arranged on the scattering layer.

7. The light scattering plate for a lighting device according to claim 5, characterized in that: The first transparent electrode and the second transparent electrode are made of a first transparent conductive film and a second transparent conductive film respectively; the first transparent conductive film is arranged on the first surface of the first transparent substrate; the light scattering plate also includes a second transparent substrate, the second transparent substrate is attached to the second surface of the first transparent substrate, and the second transparent conductive film is arranged on the second transparent substrate.

8. The light scattering plate for a lighting device according to claim 1, characterized in that: A transparent protective layer is disposed on a side of the scattering layer away from the first transparent substrate.

9. A method for manufacturing a light scattering plate for a lighting device, characterized in that The steps include: S1, firstly mixing a plurality of nano-scattering particles in an uncured photosensitive resin, so that the surface of each nano-scattering particle is infiltrated in the photosensitive resin; S2, adding oil, and fully mixing the oil and the photosensitive resin by ultrasonic emulsification to form tiny oil droplets, thereby forming a mixed emulsion of the oil and the photosensitive resin; S3, providing a first transparent substrate, and coating the mixed emulsion on a first surface of the first transparent substrate; S4, irradiating ultraviolet light to solidify the photosensitive resin in the mixed emulsion to form a scattering layer, the thickness of the scattering layer is 20-500 μm, a plurality of tiny oil droplets wrapped by the solidified photosensitive resin are arranged in the scattering layer, the size of the tiny oil droplets is 1-4 μm, a thin wall formed by the photosensitive resin is arranged between adjacent tiny oil droplets, the thickness of the thin wall is 200-500 nm, the thin wall has a first refractive index, the tiny oil droplets have a second refractive index that is not equal to the first refractive index, a plurality of nano scattering particles with Rayleigh scattering effect are dispersed in the thin wall, and the nano scattering particles are inorganic nano particles with a size of 5-40 nm.

10. The method for manufacturing a light scattering plate for an illumination device according to claim 9, characterized in that: Some of the tiny oil droplets are evenly and densely distributed on the surface of the scattering layer.

11. The method for manufacturing a light scattering plate for an illumination device according to claim 9, characterized in that: At any position of the scattering layer, there are multiple overlapping tiny oil droplets in a direction perpendicular to the plane of the scattering layer.

12. The method for manufacturing a light scattering plate for an illumination device according to claim 9, characterized in that: The photosensitive resin or the tiny oil droplets are mixed with a blue dye, and the weight of the blue dye does not exceed 20% of the total weight of the nano-scattering particles.

13. The method for manufacturing a light scattering plate for an illumination device according to claim 9, characterized in that: In the step S2, the tiny oil droplets are liquid crystal droplets; in the step S3, a first transparent electrode made of a first transparent conductive film is firstly arranged on the first surface of the first transparent substrate, and then the mixed emulsion is coated on the first surface of the first transparent substrate and the first transparent electrode; in the step S4, after the scattering layer is formed, a second transparent electrode made of a second transparent conductive film is arranged on the side of the scattering layer away from the first transparent substrate.

14. A method for manufacturing a light scattering plate for an illumination device according to claim 13, characterized in that: In the step S3, the first transparent conductive film is pre-plated on the first surface of the first transparent substrate; in the step S4, the second transparent conductive film is directly plated on the side of the scattering layer away from the first transparent substrate.

15. The method for manufacturing a light scattering plate for an illumination device according to claim 13, characterized in that: In the step S3, the first transparent conductive film is pre-plated on the first surface of the first transparent substrate; in the step S4, a second transparent substrate is provided, the second transparent conductive film is pre-arranged on the second transparent substrate, and then the second transparent substrate is bonded to the first transparent substrate so that the second transparent conductive film is on the other side of the scattering layer.

16. A lighting device, comprising a light-emitting component, characterized in that: It also includes the light scattering plate according to any one of claims 1 to 8, wherein the light scattering plate is arranged on the front side of the light emitting component.

17. A lighting device according to claim 16, characterized in that: The lighting device also includes a light box, a light outlet is arranged at the front end of the light box, the light scattering plate is arranged at the light outlet, and the light emitting component is installed in the light box and is located at the rear side of the light scattering plate.

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