Phase change display device based on cut-off phase change filter structure

Abstract

The present invention provides a phase change display device based on a cut-off phase change filter structure, the device comprising: a pixelated RGB backlight light-emitting component, comprising an LED excitation light source, a diffusion plate, a pixelated quantum dot layer and a black photoresist, wherein the LED excitation light source, the diffusion plate and the pixelated quantum dot layer are arranged in sequence from bottom to top, and the black photoresist and the pixelated quantum dot layer are located in the same layer, and are used to emit RGB light of pixel points and prevent light emission in non-pixel areas; a cut-off phase change filter structure, comprising an RG cut-off filter structure and a B filter structure, wherein the RG cut-off filter structure is used to filter out the residual blue light in the pixel points of the red and green pixelated backlight sources, and the B filter structure is used to filter the light of the pixel points of the blue pixelated backlight source to retain the blue light. The present invention adopts a cut-off phase change filter structure instead of a bandpass phase change filter structure, simplifies the manufacturing process, improves the transmittance and display effect, and adopts an isolation layer to make the filter spectrum smooth and efficient.

Description

Technical Field

[0001] The present invention relates to the technical field of display equipment, and in particular to a phase change display device based on a cut-off phase change filter structure. Background Art

[0002] Phase change display technology uses the change in the optical properties of phase change materials to display images. These materials can switch between different phases (such as from amorphous to crystalline), and through this conversion, they modulate the light that passes through. The combination of phase change display technology and quantum dot technology, combined with a suitable filter structure, allows phase change display technology to achieve efficient color modulation.

[0003] In the past, when phase-change display technology was combined with quantum dots, a bandpass filter structure was used. Through appropriate optical design, the spectrum selection of the three primary colors of RGB can be effectively realized. This structure is very suitable for the structure of white backlight sources. However, in pixel-type backlight sources, only the blue light in the red and green pixel quantum dots needs to be filtered out. In this case, if the bandpass filter structure is still used, there will be more serious light crosstalk problems, as well as problems such as low transmittance and complex process. Therefore, it is necessary to manufacture a phase-change display structure suitable for pixelated backlight sources. Summary of the invention

[0004] The present invention provides a phase change display device based on a cut-off phase change filter structure, which is used to solve the defect that the bandpass filter structure in the prior art is not suitable for pixelated backlight sources, and realizes the use of the cut-off phase change filter structure instead of the bandpass phase change filter structure, which not only simplifies the manufacturing process, but also improves the transmittance and display effect of the device.

[0005] The present invention provides a phase change display device based on a cut-off phase change filter structure, comprising:

[0006] A pixelated RGB backlight light-emitting component includes an LED excitation light source, a diffusion plate, a pixelated quantum dot layer and a black photoresist, wherein the LED excitation light source, the diffusion plate and the pixelated quantum dot layer are arranged in sequence from bottom to top, the black photoresist and the pixelated quantum dot layer are located on the same layer, and the pixelated RGB backlight light-emitting component is used to emit RGB light of pixel points and prevent light from being emitted in non-pixel areas;

[0007] A cut-off phase change filter structure is located above the pixelated RGB backlight source light-emitting component. The cut-off phase change filter structure includes an RG cut-off filter structure and a B filter structure. The RG cut-off filter structure is used to filter out the blue light remaining in the pixel points of the red and green pixelated backlight sources, and the B filter structure is used to filter the light of the pixel points of the blue pixelated backlight source to retain the blue light.

[0008] According to a phase change display device based on a cut-off phase change filter structure provided by the present invention, the wavelength of the LED excitation light source is 450nm±10nm.

[0009] According to a phase change display device based on a cut-off phase change filter structure provided by the present invention, the pixelated quantum dot layer includes pixelated red quantum dot sub-pixels, green quantum dot sub-pixels and blue LED sub-pixels.

[0010] According to a phase change display device based on a cut-off phase change filter structure provided by the present invention, the region of the blue LED sub-pixel in the pixelated quantum dot layer includes a transparent quartz substrate for transmitting the blue LED excitation light.

[0011] According to a phase change display device based on a cut-off phase change filter structure provided by the present invention, the RG cut-off filter structure comprises a full dielectric multilayer film, an isolation layer and a phase change layer arranged in sequence from bottom to top;

[0012] The all-dielectric multilayer film structures corresponding to the red quantum dot sub-pixel and the green quantum dot sub-pixel are identical and connected.

[0013] According to a phase change display device based on a cut-off phase change filter structure provided by the present invention, the all-dielectric multilayer film includes a plurality of film layer groups, each film layer group includes a first film layer and a second film layer, and the first film layer is located below the second film layer;

[0014] The refractive index of the first film layer is greater than a first preset threshold value and the extinction coefficient is less than a second preset threshold value;

[0015] The refractive index of the second film layer is less than or equal to the first preset threshold value, and the extinction coefficient is less than the second preset threshold value.

[0016] According to a phase change display device based on a cut-off phase change filter structure provided by the present invention, the number of periods of each film layer group is greater than or equal to 5, and the optical thickness of each film layer is 120nm±2.5nm.

[0017] According to a phase change display device based on a cut-off phase change filter structure provided by the present invention, the isolation layer is made of a transparent material and has a refractive index less than a third preset threshold value, and the optical thickness of the isolation layer is greater than 6 um.

[0018] According to a phase change display device based on a cut-off phase change filter structure provided by the present invention, the phase change layer includes a phase change material and transparent electrode layers located on both sides of the phase change material.

[0019] A phase change display device based on a cut-off phase change filter structure provided according to the present invention also includes a crossbar control structure, wherein the crossbar control structure includes a plurality of first electrodes arranged in parallel and a plurality of second electrodes arranged in parallel, wherein the plurality of first electrodes and the plurality of second electrodes are perpendicular and intersecting to form a cross point array, and each cross point in the cross point array is provided with a light modulation pixel unit.

[0020] The phase change display device based on the cut-off phase change filter structure provided by the present invention adopts the cut-off phase change filter structure to replace the original bandpass phase change filter structure in the pixel-type backlight display structure. The filter component has high transmittance, simple process flow, fast device response speed, large display color gamut, strong color restoration ability, etc., which not only simplifies the manufacturing process, but also improves the transmittance and display effect of the device, thereby solving the problems existing in the traditional bandpass filter structure in the pixel-type backlight display structure; in order to solve the noise problem caused by the cut-off filter structure, an isolation layer is also used to optimize the effect, so that the filter spectrum of the device is smooth and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 It is a schematic structural diagram of a phase change display device based on a cut-off phase change filter structure provided by the present invention;

[0023] Figure 2 It is a schematic diagram of the all-dielectric multilayer film structure in the RG cut-off filter structure of the phase change display device based on the cut-off phase change filter structure provided by the present invention;

[0024] Figure 3 It is a schematic diagram of the phase change layer structure in the RG cut-off type filter structure of the phase change display device based on the cut-off type phase change filter structure provided by the present invention;

[0025] Figure 4 It is a schematic diagram of a crossbar structure in a phase change display device based on a cut-off phase change filter structure provided by the present invention.

[0026] 101 is an LED excitation light source; 102 is a diffusion plate; 103 is a pixelated red quantum dot; 104 is a pixelated green quantum dot; 105 is a black photoresist; 106 is an RG cut-off filter structure; 107 is an isolation layer; 108 is a phase change layer; 201 is a first film layer; 202 is a second film layer; 301 is a transparent electrode layer; 302 is a phase change material. DETAILED DESCRIPTION

[0027] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below in conjunction with the drawings of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] Combine the following Figure 1 The present invention is a phase change display device based on a cut-off phase change filter structure, comprising:

[0029] A pixelated RGB backlight light-emitting component includes an LED (Light Emitting Diode) excitation light source 101, a diffusion plate 102, a pixelated quantum dot layer and a black photoresist 105. The LED excitation light source 101, the diffusion plate 102 and the pixelated quantum dot layer are arranged in sequence from bottom to top. The black photoresist 105 and the pixelated quantum dot layer are located in the same layer. The pixelated RGB backlight light-emitting component is used to emit RGB light of pixel points and prevent light from being emitted in non-pixel areas.

[0030] The cut-off phase change filter structure is located above the pixelated RGB backlight source light-emitting component. The cut-off phase change filter structure includes an RG cut-off filter structure 106 and a B filter structure. The RG cut-off filter structure 106 is used to filter out the blue light remaining in the pixel points of the red and green pixelated backlight sources, and the B filter structure is used to filter the light of the pixel points of the blue pixelated backlight source to retain the blue light.

[0031] The pixelated quantum dot layer includes pixelated red quantum dots 103 and pixelated green quantum dots 104. The pixelated red quantum dots 103 and the pixelated green quantum dots 104 are located in the same layer, and there is a certain distance between them. The pixelated red quantum dots 103 and the pixelated green quantum dots 104 cover the left part of the diffuser 102.

[0032] The black photoresist 105 is located in the non-pixel area of ​​the layer where the pixelated quantum dot layer is located, and is used to block the light in the non-pixel area.

[0033] The B filter structure may include an isolation layer 107 and a phase change layer 108, which are used to filter the light of the pixel points of the blue pixelated backlight source to retain the blue light. The B filter structure can be extended and covered on the RG cut-off filter structure 106. In this case, the B filter structure filters the light to retain the blue light, red light and green light. Figure 1 The color of the arrow in the middle represents the color of the corresponding light.

[0034] The phase change display device based on the cut-off phase change filter structure provided in this embodiment is suitable for various display devices, including but not limited to augmented reality / virtual reality devices (AR / VR), vehicle-mounted displays, mobile device displays, etc.

[0035] This embodiment adopts a cut-off phase change filter structure to replace the original bandpass phase change filter structure in the pixel-type backlight display structure. The filter component has high transmittance, simple process flow, fast device response speed, large display color gamut, strong color reproduction ability, etc. It not only simplifies the manufacturing process, but also improves the transmittance and display effect of the device, thereby solving the problems existing in the traditional bandpass filter structure in the pixel-type backlight display structure.

[0036] On the basis of the above-mentioned embodiment, the wavelength of the LED excitation light source in this embodiment is 450nm±10nm.

[0037] On the basis of the above-mentioned embodiment, the pixelated quantum dot layer in this embodiment includes pixelated red quantum dot sub-pixels, green quantum dot sub-pixels and blue LED sub-pixels.

[0038] On the basis of the above-mentioned embodiment, the region of the blue LED sub-pixel in the pixelated quantum dot layer in this embodiment includes a transparent quartz substrate for transmitting the blue LED excitation light.

[0039] On the basis of the above-mentioned embodiment, the RG cut-off type filter structure described in this embodiment includes a full dielectric multilayer film, an isolation layer and a phase change layer arranged in sequence from bottom to top;

[0040] The all-dielectric multilayer film structures corresponding to the red quantum dot sub-pixel and the green quantum dot sub-pixel are identical and connected. The all-dielectric multilayer film may include multiple layers of dielectrics with different refractive indices, different extinction coefficients, different materials or different thicknesses. This embodiment does not limit the number of dielectric layers.

[0041] Based on the above embodiments, Figure 2 As shown, the all-dielectric multilayer film in this embodiment includes a plurality of film layer groups, each of which includes a first film layer 201 and a second film layer 202, wherein the first film layer 201 is located below the second film layer 202;

[0042] The refractive index of the first film layer 201 is greater than a first preset threshold value and the extinction coefficient is less than a second preset threshold value;

[0043] The refractive index of the second film layer 202 is less than or equal to the first preset threshold and the extinction coefficient is less than the second preset threshold.

[0044] The all-dielectric multilayer film structure is (LH)x, where H is the first film layer 201, which is a high refractive index and low extinction coefficient film layer; L is the second film layer 202, which is a low refractive index and low extinction coefficient film layer; and x is the number of film layer group periods.

[0045] Preferably, the high refractive index medium material is one of TiO2, ZnO and ZnS, and the low refractive index material is one of SiO2, Al2O3 and MgF2.

[0046] On the basis of the above-mentioned embodiment, in this embodiment, the number of periods of each film layer group is greater than or equal to 5, and the optical thickness of each film layer is 120 nm±2.5 nm.

[0047] On the basis of the above-mentioned embodiment, in this embodiment, the isolation layer is made of a transparent material and has a refractive index less than a third preset threshold value, and the optical thickness of the isolation layer is greater than 6 um.

[0048] The isolation layer is composed of a low-refractive-index transparent material, and its optical thickness is greater than 6 um.

[0049] This embodiment optimizes the effect by using an isolation layer, so that the filtering spectrum of the device is smooth and efficient, thereby solving the clutter problem caused by the cut-off filter structure.

[0050] Based on the above embodiments, Figure 3 As shown, the phase change layer in this embodiment includes a phase change material 302 and a transparent electrode layer 301 located on both sides of the phase change material.

[0051] The phase change material 302 of the phase change material layer can be converted between crystalline and amorphous states under electrical stimulation or laser stimulation, thereby changing the transmittance of the phase change layer. The two transparent electrode layers 301 sandwiching the phase change material 302 in the phase change layer can control the crystallization state of the phase change material by applying voltage.

[0052] Specifically, a pulse current or laser pulse of medium intensity is applied to the phase change material 302. Under the action of the current or laser pulse, the temperature of the phase change material 302 rises to a temperature range above the crystallization temperature and below the melting temperature and is maintained for a certain period of time. At this time, the crystal lattice is orderly arranged to form a crystalline state, realizing the transition from amorphous to crystalline.

[0053] A short and strong current or laser pulse is applied to the phase change material 302, so that the temperature of the phase change material 302 is raised to above the melting temperature, so that the long-range order of the crystalline state is destroyed. The pulse falling edge is very short, so that the phase change material 302 is quickly cooled to below the crystallization temperature, so that the phase change material 302 is fixed in the amorphous state, and the transition from the crystalline state to the amorphous state is achieved.

[0054] This embodiment filters the complex light emitted by the multicolor quantum dot light-emitting component by the change in transmittance of the phase change material 302 of the phase change layer when it transforms between the amorphous state and the crystalline state, thereby obtaining monochromatic light of the required wavelength and intensity, thereby realizing color display.

[0055] The phase change material 302 may include the following chalcogenides and their alloys, including but not limited to GST, GSST, IST, GeTe, SbTe, BiTe, InSb, InSe, GeSb, SbSe, GaSb, GaSb, GeSbTe, AgInSbTe, InSbTe, AgSbTe, Ag2In4Sb 76 Te 17 (AIST). In addition, the atomic percentages in the above chemical formulas may be variable. The phase change material 302 may further include at least one dopant, such as C, N.

[0056] Preferably, the phase change material is Sb2Te3. At the same thickness, the transmittance change of Sb2Te3 before and after the phase change is the largest, and the phase change temperature of Sb2Te3 is low. The voltage or laser amplitude required for the transition is low and the pulse width is narrow, which is convenient for reducing the energy consumption of the entire device and improving the response speed of the phase change material 302.

[0057] The thickness of the phase change material layer 302 is less than 100nm. Since the increase in the thickness of the phase change material 302 will reduce the transmittance of visible light, and the temperature required for the crystallization of the phase change material 302 is also higher, the more suitable thickness is 30nm. The phase change material 302 of the phase change layer can be driven by laser or voltage. When driven by voltage, the transparent electrode layer 301 on both sides of the phase change material 302 applies voltage to cause the phase change material 302 to undergo phase change.

[0058] The transmittance of the phase change layer in the RG cutoff filter structure varies greatly in different states. The phase change material 302 is stable in the crystalline and amorphous states, so the voltage or laser can be removed when the phase change material 302 is in a stable state, so the power consumption of the entire display device during the display process is very low.

[0059] The phase change material 302 switches between the crystalline state and the amorphous state very quickly, that is, the time required for a single pixel to change from dark to bright or from bright to dark is very short, about less than 100ns, which fully meets the requirements in various scenarios.

[0060] Based on the above embodiment, the present embodiment also includes a crossbar control structure, wherein the crossbar control structure includes a plurality of first electrodes arranged in parallel and a plurality of second electrodes arranged in parallel, wherein the plurality of first electrodes and the plurality of second electrodes are perpendicular and intersecting to form a cross point array, and each cross point in the cross point array is provided with a light modulation pixel unit.

[0061] The first electrode in the crossbar control structure can be a horizontal electrode, and the second electrode can be a vertical electrode. Multiple horizontal electrodes and multiple vertical electrodes form a crossbar array, and there is a light modulation pixel unit in the middle of each crossbar. Figure 4 shown.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A phase change display device based on a cut-off phase change filter structure, characterized in that: include: A pixelated RGB backlight light-emitting component, comprising an LED excitation light source, a diffusion plate, a pixelated quantum dot layer and a black photoresist, wherein the LED excitation light source, the diffusion plate and the pixelated quantum dot layer are arranged in sequence from bottom to top, the black photoresist and the pixelated quantum dot layer are located on the same layer, the pixelated RGB backlight light-emitting component is used to emit RGB light of pixel points and prevent light from being emitted from non-pixel areas, and the pixelated red quantum dots and the pixelated green quantum dots in the pixelated quantum dot layer cover the left portion of the diffusion plate; A cut-off phase change filter structure is located on the pixelated RGB backlight source light-emitting component, and the cut-off phase change filter structure includes an RG cut-off filter structure and a B filter structure. The RG cut-off filter structure is used to filter out the residual blue light in the pixel points of the red and green pixelated backlight sources, and the B filter structure is used to filter the light of the pixel points of the blue pixelated backlight source to retain the blue light. The B filter structure includes an isolation layer and a phase change layer. The B filter structure is extended and covers on the RG cut-off filter structure. The B filter structure filters the light to retain the blue light, red light and green light.

2. The phase change display device based on the cut-off phase change filter structure according to claim 1, characterized in that: The wavelength of the LED excitation light source is 450nm±10nm.

3. The phase change display device based on the cut-off phase change filter structure according to claim 1, characterized in that: The pixelated quantum dot layer includes pixelated red quantum dot sub-pixels, green quantum dot sub-pixels, and blue LED sub-pixels.

4. The phase change display device based on the cut-off phase change filter structure according to claim 3, characterized in that: The region of the blue LED sub-pixel in the pixelated quantum dot layer includes a transparent quartz substrate for transmitting the blue LED excitation light.

5. The phase change display device based on the cut-off phase change filter structure according to claim 3, characterized in that: The RG cut-off filter structure includes a full dielectric multilayer film, an isolation layer and a phase change layer arranged in sequence from bottom to top; The all-dielectric multilayer film structures corresponding to the red quantum dot sub-pixel and the green quantum dot sub-pixel are identical and connected.

6. The phase change display device based on the cut-off phase change filter structure according to claim 5, characterized in that: The all-dielectric multilayer film includes a plurality of film layer groups, each of which includes a first film layer and a second film layer, wherein the first film layer is located below the second film layer; The refractive index of the first film layer is greater than a first preset threshold value and the extinction coefficient is less than a second preset threshold value; The refractive index of the second film layer is less than or equal to the first preset threshold value, and the extinction coefficient is less than the second preset threshold value.

7. The phase change display device based on the cut-off phase change filter structure according to claim 6, characterized in that: The number of periods of each film layer group is greater than or equal to 5, and the optical thickness of each film layer is 120nm±2.5nm.

8. The phase change display device based on the cut-off phase change filter structure according to claim 5, characterized in that: The isolation layer is made of a transparent material and has a refractive index less than a third preset threshold value. The optical thickness of the isolation layer is greater than 6 um.

9. The phase change display device of the cut-off phase change filter structure according to claim 5, characterized in that: The phase change layer includes a phase change material and a transparent electrode layer located on both sides of the phase change material.

10. The phase change display device based on a cut-off phase change filter structure according to any one of claims 1 to 9, characterized in that: It also includes a crossbar control structure, which includes a plurality of first electrodes arranged in parallel and a plurality of second electrodes arranged in parallel, wherein the plurality of first electrodes and the plurality of second electrodes are perpendicular and intersecting to form a cross-point array, and each cross-point in the cross-point array is provided with a light modulation pixel unit.

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