Reflective device and display device

Abstract

The present invention discloses a reflective device and a display device. Due to the addition of a light conversion structure arranged in a resonant cavity, the light conversion structure can improve the utilization rate of incident light, effectively utilize the wavelength range light outside the set wavelength range that is not reflected by the resonant cavity and is repeatedly oscillated and absorbed in the resonant cavity, and convert this part of the incident non-set wavelength range light into the set wavelength range light, thereby increasing the proportion of reflected light of the reflective device and improving the reflection efficiency of the reflective device.

Description

Technical Field

[0001] The present invention relates to the field of display technology, and in particular to a reflective device and a display apparatus. Background Art

[0002] At present, an existing reflective device is to use Figure 1 The Fabry-Perot resonant cavity shown has an anti-reflection layer 103, a thin metal absorption layer 101 and a reflector 102; by adjusting the optical path in the cavity, reflection of light of a specific wavelength can be achieved, and other wavelengths in the incident light repeatedly oscillate in the cavity and are absorbed by the thin metal absorption layer 101, and eventually the energy is exhausted. This reflective device has low light utilization efficiency. Summary of the invention

[0003] In view of this, an embodiment of the present invention provides a reflective device and a display device to solve the problem of low light utilization rate of existing reflective devices.

[0004] Therefore, an embodiment of the present invention provides a reflective device, comprising: a resonant cavity that reflects light within a set wavelength range, and a light conversion structure arranged in the resonant cavity, wherein the light conversion structure is used to convert incident light outside the set wavelength range into light within the set wavelength range.

[0005] In a possible implementation, in the above-mentioned reflective device provided in an embodiment of the present invention, the resonant cavity specifically includes: a thin metal absorption layer arranged on one side of the cavity, and a reflector arranged on the other side of the cavity; there is an optical path between the thin metal absorption layer and the reflector that matches the light in the set wavelength range, a medium is filled in the optical path, and the light conversion structure is arranged in the medium.

[0006] In a possible implementation, in the above-mentioned reflective device provided by an embodiment of the present invention, the resonant cavity further includes: an anti-reflection film disposed on the light-emitting side of the thin metal absorption layer.

[0007] In a possible implementation, in the above-mentioned reflective device provided in an embodiment of the present invention, the medium includes one or a combination of air, an inorganic film and an organic film.

[0008] In a possible implementation, in the above-mentioned reflective device provided by an embodiment of the present invention, the thickness of the light conversion structure is in the range of 0 to N nm; wherein N = (central wavelength of the set wavelength range / 2) / material refractive index of the light conversion structure.

[0009] In a possible implementation, in the above-mentioned reflective device provided by an embodiment of the present invention, the light in the set wavelength range is monochromatic light.

[0010] In a possible implementation, in the above-mentioned reflective device provided by an embodiment of the present invention, the monochromatic light is low-frequency light in the visible light band, and the light conversion structure includes a down-conversion material for converting high-frequency light and medium-frequency light in the visible light band into the low-frequency light.

[0011] In a possible implementation, in the above-mentioned reflective device provided by an embodiment of the present invention, the monochromatic light is high-frequency light in the visible light band, and the light conversion structure includes an up-conversion material for converting low-frequency light and medium-frequency light in the visible light band into the high-frequency light.

[0012] In a possible implementation, in the above-mentioned reflective device provided in an embodiment of the present invention, the monochromatic light is intermediate frequency light in the visible light band, and the light conversion structure includes an up-conversion material for converting low frequency light in the visible light band into the intermediate frequency light, and / or a down-conversion material for converting high frequency light in the visible light band into the intermediate frequency light.

[0013] In a possible implementation, in the above-mentioned reflective device provided by an embodiment of the present invention, the down-conversion material includes: one or a combination of an inorganic light-emitting material and an organic light-emitting material.

[0014] In a possible implementation, in the above-mentioned reflective device provided by an embodiment of the present invention, the up-conversion material includes: an inorganic compound doped with rare earth ions.

[0015] On the other hand, an embodiment of the present invention further provides a display device, including multiple pixel units, each pixel unit includes multiple of the above-mentioned reflective devices provided by an embodiment of the present invention, and the reflective devices belonging to the same pixel unit reflect light in different wavelength ranges.

[0016] The beneficial effects of the embodiments of the present invention include:

[0017] A reflective device and a display device provided by an embodiment of the present invention have an optical conversion structure arranged in a resonant cavity. The optical conversion structure can improve the utilization rate of incident light, effectively utilize the wavelength range light outside the set wavelength range that is not reflected by the resonant cavity and is repeatedly oscillated and absorbed in the resonant cavity, and convert this part of the incident non-set wavelength range light into the set wavelength range light, thereby increasing the proportion of reflected light of the reflective device and improving the reflection efficiency of the reflective device. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the structure of a reflective device in the prior art;

[0019] Figure 2 A schematic structural diagram of a reflective device provided in an embodiment of the present invention;

[0020] Figure 3a and Figure 3b They are schematic diagrams of specific structures of reflective devices provided in embodiments of the present invention;

[0021] Figure 4 A schematic diagram of the structure of a display device provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0022] The specific implementation manner of the reflective device and the display device provided by the embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

[0023] The shapes and sizes of the components in the drawings do not reflect the actual proportions of the reflective device, and are only intended to illustrate the contents of the present invention.

[0024] The embodiment of the present invention provides a reflective device, such as Figure 2 As shown, it includes: a resonant cavity 100 for reflecting light within a set wavelength range, and a light conversion structure 200 arranged in the resonant cavity 100, and the light conversion structure 200 is used to convert incident light outside the set wavelength range into light within the set wavelength range.

[0025] Specifically, in the above-mentioned reflective device provided in the embodiment of the present invention, since the light conversion structure 200 arranged in the resonant cavity 100 is added, the light conversion structure 200 can improve the utilization rate of the incident light, and effectively utilize the wavelength range light outside the set wavelength range that is not reflected by the resonant cavity 100 and is repeatedly oscillated and absorbed in the resonant cavity 100, and convert this part of the incident non-set wavelength range light into the set wavelength range light, thereby increasing the proportion of reflected light of the reflective device to improve the reflection efficiency of the reflective device.

[0026] In specific implementation, the resonant cavity 100 in the above-mentioned reflective device provided in the embodiment of the present invention may adopt a variety of implementation structures, for example, a Fabry-Perot resonant cavity 100 may be adopted.

[0027] Specifically, in the above-mentioned reflective device provided by the embodiment of the present invention, no matter what structure of the resonant cavity 100 is adopted, Figure 3a and Figure 3b As shown, the resonant cavity 100 generally needs to include: a thin metal absorption layer 110 arranged on one side of the cavity, and a reflector 120 arranged on the other side of the cavity; there is an optical path a between the thin metal absorption layer 110 and the reflector 120 that matches the light in the set wavelength range, and the optical path a is filled with a medium 130, and the light conversion structure 200 is arranged in the medium 130.

[0028] Specifically, in the above-mentioned reflective device provided in the embodiment of the present invention, the medium 130 filled in the optical path a may include air, one or a combination of inorganic thin films and organic thin films. For example, only air may be filled as the medium 130, or part of the inorganic thin film and part of the air may be filled as the medium 130, which is not limited here. When only air is used as the medium 130, in order to facilitate the manufacture of the reflective device, in the specific implementation, such as Figure 3a As shown, the light conversion structure 200 can be disposed on the surface of the thin metal absorption layer 110 facing the reflector 120; or Figure 3b As shown, the light conversion structure 200 is disposed on the surface of the reflector 120 facing the thin metal absorption layer 110, which is not limited here. When part or all of the inorganic thin film and the organic thin film are used as the medium 130, in specific implementation, the light conversion structure 200 can be disposed between any two film layers between the thin metal absorption layer 110 and the reflector 120 according to manufacturing requirements, which is not limited here.

[0029] Specifically, in the above-mentioned reflective device provided in an embodiment of the present invention, the size of the optical path a between the thin metal absorption layer 110 and the reflector 120 is related to the light in the set wavelength range and the material and thickness of the medium 130. The specific relationship is: a=(n1*d1+n2*d2...)*center wavelength of the set wavelength range / 2; wherein d1, d2... are the thicknesses of each film layer of the medium 130, and n1, n2... are the refractive indices of each film layer of the medium 130.

[0030] And, specifically, in the above-mentioned reflective device provided by the embodiment of the present invention, the thickness of the light conversion structure 200 is related to the set wavelength range and the material of the light conversion structure, and the specific relationship is: the thickness of the light conversion structure 200 is in the range between 0 and N nm; wherein N = (center wavelength of the set wavelength range / 2) / refractive index of the material of the light conversion structure 200.

[0031] In a specific implementation, in the above-mentioned reflective device provided in the embodiment of the present invention, in order to improve the light reflection efficiency at the thin metal absorption layer 110, as shown in FIG. Figure 3a and Figure 3b As shown, the resonant cavity 100 may also include: an anti-reflection film 140 arranged on the light-emitting side of the thin metal absorption layer 110 to increase the proportion of the incident light entering the optical path a between the thin metal absorption layer 110 and the reflector 120, and avoid the proportion of the incident light directly reflected by the surface of the thin metal absorption layer 110 facing the light-emitting side, thereby improving the light reflectivity by improving the utilization rate of the incident light.

[0032] In specific implementation, the light of the set wavelength range that can be reflected by the above-mentioned reflective device provided in the embodiment of the present invention is generally monochromatic light, and the monochromatic light is generally in the visible light range, that is, the wavelength range reflected by the reflective device only covers a single color band, so that the reflective device can be used as a monochromatic light emitter for display or lighting, and the monochromatic light can also be in the infrared band, so that the reflective device can be used in sensors. Of course, in specific implementation, according to actual needs, it can also be set that the wavelength range reflected by the reflective device covers multiple color bands, which is not limited here.

[0033] Furthermore, in the specific implementation, in the above-mentioned reflective device provided in the embodiment of the present invention, in order to realize the function of the light conversion structure 200 to convert the incident light of the non-set wavelength range into the light of the set wavelength range to improve the light utilization rate, the material selected by the light conversion structure 200 is related to the set wavelength range of reflection. The following is an example of the specific material selection of the light conversion structure 200, taking the wavelength range reflected by the reflective device covering only a single color band as an example.

[0034] In specific implementation, in the above-mentioned reflective device provided in the embodiment of the present invention, when the monochromatic light that the reflective device needs to reflect is low-frequency light in the visible light band, the light conversion structure 200 generally includes a down-conversion material for converting high-frequency light and medium-frequency light in the visible light band into low-frequency light. Specifically, the down-conversion material may include: one or a combination of inorganic light-emitting materials and organic light-emitting materials, such as quantum dot materials and fluorescent materials. Among them, the organic light-emitting material can be an organic small molecule light-emitting material or an organic high molecular polymer light-emitting material, which is not limited here. In addition, when a plurality of down-conversion materials are selected as the light conversion structure 200, each material can be arranged in a film layer, and each film layer can be adjacent or spaced, or each material can be mixed in the same film layer, which is not limited here.

[0035] For example, when the reflective device needs to reflect red light, the material of the light conversion structure 200 is a down-conversion material for converting blue light and green light into red light. Specifically, the down-conversion material can be selected from red quantum dots, red fluorescent materials and other red luminescent materials, which are not limited here.

[0036] In specific implementation, in the above-mentioned reflective device provided in the embodiment of the present invention, when the monochromatic light that the reflective device needs to reflect is high-frequency light in the visible light band, the light conversion structure 200 generally includes an up-conversion material for converting low-frequency light and medium-frequency light in the visible light band into high-frequency light. Specifically, the up-conversion material may include: an inorganic compound doped with rare earth ions. For example, according to the high-frequency light to be converted, one or more rare earth ions of corresponding concentrations and proportions may be doped in inorganic compounds such as fluorides, oxides, sulfur-containing compounds, fluoride oxides, and halides. For example, NaYF4, which currently has the highest up-conversion luminescence efficiency, may be selected as the matrix material, doped with Yb:Tm:Er=18~60:0~0.2:0~2. In addition, when multiple up-conversion materials are selected as the light conversion structure 200, each material may be arranged in a film layer, and each film layer may be adjacent or spaced, or each material may be mixed in the same film layer, which is not limited here.

[0037] For example, when the reflective device needs to reflect blue light, the material of the light conversion structure 200 is an up-conversion material for converting red light and green light into blue light. Specifically, the up-conversion material can be selected from a material whose matrix material, that is, an inorganic compound, is NaYF4 and doped with Yb:Tm:Er=20:0.2:0-0.5.

[0038] In specific implementation, in the above-mentioned reflective device provided in the embodiment of the present invention, when the monochromatic light that the reflective device needs to reflect is the intermediate frequency light in the visible light band, the light conversion structure 200 generally includes an up-conversion material for converting the low frequency light in the visible light band into the intermediate frequency light, and / or a down-conversion material for converting the high frequency light in the visible light band into the intermediate frequency light. In addition, in order to maximize the light utilization rate, the light conversion structure 200 preferably needs to include both the up-conversion material and the down-conversion material. Specifically, the down-conversion material may include: one or a combination of inorganic luminescent materials and organic luminescent materials, such as quantum dot materials and fluorescent materials. Among them, the organic luminescent material may be an organic small molecule luminescent material or an organic high molecular polymer luminescent material, which is not limited here. Specifically, the up-conversion material may include: an inorganic compound doped with rare earth ions. For example, according to the high frequency light to be converted, one or more rare earth ions of corresponding concentrations and proportions may be doped in inorganic compounds such as fluorides, oxides, sulfur-containing compounds, fluoride oxides, and halides. For example, NaYF4, which has the highest up-conversion luminescence efficiency, can be selected as the matrix material, and doped with Yb:Tm:Er=18~60:0~0.2:0~2. Furthermore, when multiple up-conversion materials are selected as the light conversion structure 200, each material can be arranged in a film layer, and each film layer can be adjacent or spaced, or each material can be mixed in the same film layer, which is not limited here.

[0039] For example, when the reflective device needs to reflect green light, the material of the light conversion structure 200 can include both an up-conversion material for converting red light into green light and a down-conversion material for converting blue light into green light. Specifically, the down-conversion material can be selected from green quantum dots, green fluorescent materials and other green organic light-emitting materials, which are not limited here. Specifically, the up-conversion material can be selected from a material whose matrix material, that is, an inorganic compound, is NaYF4, doped with Yb:Tm:Er=18~25:0:2.

[0040] Based on the same inventive concept, an embodiment of the present invention further provides a display device, which can be any product or component with a display function, such as a mobile phone, a tablet computer, a television, a monitor, a laptop computer, a digital photo frame, a navigator, etc. The implementation of the display device can refer to the embodiment of the above-mentioned reflective device, and the repeated parts will not be repeated.

[0041] Specifically, an embodiment of the present invention provides a display device, such as Figure 4 As shown, it includes a plurality of pixel units 01, each pixel unit 01 includes a plurality of the above-mentioned reflective devices 02 provided by the embodiment of the present invention as sub-pixel units, and the wavelength ranges of the reflected light of each reflective device 02 belonging to the same pixel unit 01 are different. Figure 4 As shown, a reflective device that reflects red light R, a reflective device that reflects green light G, and a reflective device that reflects blue light B can be selected to form a pixel unit. Since the reflective device provided by the embodiment of the present invention with high reflection efficiency is used as a sub-pixel to form a display device, the ambient light can be better utilized for reflective display to ensure a better reflectivity.

[0042] The above-mentioned reflective device and display device provided by the embodiments of the present invention, due to the addition of a light conversion structure arranged in the resonant cavity, the light conversion structure can improve the utilization rate of the incident light, effectively utilize the wavelength range light outside the set wavelength range that is not reflected by the resonant cavity and is repeatedly oscillated and absorbed in the resonant cavity, and convert this part of the incident non-set wavelength range light into the set wavelength range light, thereby increasing the proportion of reflected light of the reflective device, so as to improve the reflection efficiency of the reflective device.

[0043] Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A reflective device, characterized in that: include: A resonant cavity reflecting light within a set wavelength range, and a light conversion structure arranged in the resonant cavity, wherein the light conversion structure is used to convert incident light not within the set wavelength range into light within the set wavelength range.

2. The reflective device according to claim 1, characterized in that: The resonant cavity specifically includes: a thin metal absorption layer arranged on one side of the cavity, and a reflector arranged on the other side of the cavity; there is an optical path between the thin metal absorption layer and the reflector that matches the light in the set wavelength range, a medium is filled in the optical path, and the light conversion structure is arranged in the medium.

3. The reflective device according to claim 2, characterized in that: The resonant cavity further comprises an anti-reflection film arranged on the light-emitting side of the thin metal absorption layer.

4. The reflective device according to claim 2, characterized in that: The medium includes one or a combination of air, inorganic thin films and organic thin films.

5. The reflective device according to claim 1, characterized in that: The thickness of the light conversion structure is in the range of 0 to N nm, wherein N=(the central wavelength of the set wavelength range / 2) / the material refractive index of the light conversion structure.

6. The reflective device according to claim 1, characterized in that: The light in the set wavelength range is monochromatic light.

7. The reflective device according to claim 6, characterized in that: The monochromatic light is low-frequency light in the visible light band, and the light conversion structure includes a down-conversion material for converting high-frequency light and medium-frequency light in the visible light band into the low-frequency light.

8. The reflective device according to claim 6, characterized in that: The monochromatic light is high-frequency light in the visible light band, and the light conversion structure includes an up-conversion material for converting low-frequency light and medium-frequency light in the visible light band into the high-frequency light.

9. The reflective device according to claim 6, characterized in that: The monochromatic light is intermediate frequency light in the visible light band, and the light conversion structure includes an up-conversion material for converting low frequency light in the visible light band into the intermediate frequency light, and / or a down-conversion material for converting high frequency light in the visible light band into the intermediate frequency light.

10. The reflective device according to claim 7 or 9, characterized in that: The down conversion material includes: one or a combination of an inorganic light-emitting material and an organic light-emitting material.

11. The reflective device according to claim 8 or 9, characterized in that: The up-conversion material includes: an inorganic compound doped with rare earth ions.

12. A display device, characterized in that: It comprises a plurality of pixel units, each pixel unit comprises a plurality of reflective devices as claimed in any one of claims 1 to 11, and the reflective devices belonging to the same pixel unit reflect light in different wavelength ranges.

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