WO2019153791A1 - Pixel structure, display panel, display apparatus, and display method - Google Patents

Abstract

A pixel structure, a display panel, a display apparatus, and a display method. The pixel structure (10) comprises: a pixel area (101), a non-pixel area (102) positioned at one side of the pixel area (101), a light-splitting component (100), a first waveguide (2), and a second waveguide (3). The light-splitting component (100) is positioned in the non-pixel area (102) and is configured to disperse incident light into a plurality of coloured lights; the first waveguide (2) is positioned in the non-pixel area (102); and the second waveguide (3) is positioned in the pixel area (101). The first waveguide (2) comprises a first end (21) near to the pixel area (101) and the second waveguide (3) comprises a first end (31) near to the non-pixel area (102), the first end (21) of the first waveguide (2) and the first end (31) of the second waveguide (3) being connected; the first waveguide (2) is configured to receive one of the plurality of coloured lights from the light-splitting component (100) and transmit the one of the plurality of coloured lights to the second waveguide (3), and the second waveguide (3) is configured to emit at a predetermined position the one of the plurality of coloured lights transmitted to the second waveguide (3). The pixel structure (10) has a simple structure and does not require a liquid crystal layer, which is beneficial to implementing thin apparatuses. In addition, the rate of light utilisation of the present pixel structure (10) is higher than display panels using a planar grating.

Description

Pixel structure, display panel, display device and display method

The present application claims the priority of the Chinese Patent Application No. 201101136336.9 filed on Feb. 09. 20, the entire disclosure of which is hereby incorporated by reference.

Technical field

At least one embodiment of the present disclosure is directed to a pixel structure, a display panel, a display device, and a display method.

Background technique

Generally, a grating refers to an optical element that enables periodic amplitude modulation of the amplitude or phase of incident light or both. The grating can be classified into a transmissive grating and a reflective grating depending on whether the grating is used for transmitting light or for reflecting light. When multi-color light is incident on the grating, the light of different wavelengths is dispersed after passing through the grating, and the positions of the diffraction spectra of the same level (except the zero order) of different wavelengths do not coincide. Therefore, the grating has a light splitting action and can be used as a light splitting element.

Summary of the invention

At least one embodiment of the present disclosure provides a pixel structure including: a pixel region, a non-pixel region located on one side of the pixel region, a curved grating, a first waveguide, and a second waveguide. A curved grating is located in the non-pixel region and configured to disperse light into a plurality of colored lights; a first waveguide is located in the non-pixel region; and a second waveguide is located in the pixel region. The first waveguide includes a first end adjacent to the pixel region, the second waveguide includes a first end adjacent to the non-pixel region, and the first end of the first waveguide and the second waveguide One end is coupled; the first waveguide is configured to conduct one of the plurality of colored lights into the second waveguide, the second waveguide configured to emit colored light transmitted thereto at a predetermined position.

For example, in a pixel structure provided by an embodiment of the present disclosure, the beam splitting component includes a curved grating.

For example, in a pixel structure according to an embodiment of the present disclosure, a light emitting surface of the curved grating is a concave surface, the concave surface faces the first waveguide; and the first waveguide further includes a second portion away from the pixel region. And transmitting one of a plurality of color lights dispersed via the curved grating to the second end of the first waveguide through the concave surface to cause one of the plurality of color lights to be incident into the first waveguide.

For example, a pixel structure provided by an embodiment of the present disclosure further includes a reflective structure; wherein, a light emitting surface of the curved grating is a concave surface, the concave surface faces the reflective structure; and the first waveguide further includes a distance away from the pixel a second end of the region, the reflective structure configured to reflect one of a plurality of color lights dispersed through the curved grating and emitted through the concave surface to a second end of the first waveguide to cause the plurality of One of the colored lights is incident into the first waveguide.

For example, in a pixel structure provided by an embodiment of the present disclosure, the curved grating is a reflective grating configured to enter and exit light from the same side of the curved grating.

For example, in a pixel structure provided by an embodiment of the present disclosure, the curved grating is a Roland circular grating.

For example, in a pixel structure according to an embodiment of the present disclosure, at least part of the curved grating is a curved blazed grating, and a light emitting surface of the curved blazed grating includes a grating surface having a curved surface and a concave and convex surface located on the grating surface. The concave and convex structure includes a groove surface having an angle with a tangent of the grating surface.

For example, in a pixel structure provided by an embodiment of the present disclosure, the first waveguide further includes a second end away from the pixel region; the beam splitting component includes a plane grating and a lens, and the plane grating is configured to be incident Light is dispersed into a plurality of color lights, and the lens is configured to adjust the plurality of color lights such that one of a plurality of color lights dispersed via the planar grating is incident on the lens and then incident on a second of the first waveguide The end is such that one of the plurality of color lights is incident into the first waveguide.

For example, in a pixel structure provided by an embodiment of the present disclosure, the planar grating includes a planar blazed grating.

For example, in a pixel structure provided by an embodiment of the present disclosure, the first waveguide includes a first portion and a second portion connected in parallel, and an end of the first portion away from the pixel region and the second portion are far away One end of the pixel region is connected, and one end of the first portion adjacent to the pixel region and one end of the second portion adjacent to the pixel region are connected.

For example, in a pixel structure provided by an embodiment of the present disclosure, the first waveguide includes: a first layer, a second layer, and a waveguide layer. a second layer is disposed on the first layer; a waveguide layer is disposed between the first layer and the second layer; a refractive index of a material of the waveguide layer is greater than a refractive index of a material of the first layer And a refractive index of the material of the second layer; one of the plurality of color lights being conducted to the second waveguide via total reflection at the waveguide layer.

For example, in a pixel structure provided by an embodiment of the present disclosure, the waveguide layer is an electro-index change material.

For example, in a pixel structure provided by an embodiment of the present disclosure, the first waveguide is a Bragg-type diffraction grating, and the Bragg-type grating has a period in a direction from the non-pixel region to the pixel region. Varying refractive index.

For example, a pixel structure according to an embodiment of the present disclosure further includes a first electrode, a second electrode, and a third electrode, wherein the first electrode and the third electrode are configured to be in accordance with the first data voltage signal A first portion of a waveguide applies a first electric field; the second electrode and the third electrode are configured to apply a second electric field to the second portion of the first waveguide in accordance with a second data voltage signal.

For example, a pixel structure provided by an embodiment of the present disclosure further includes a common electrode, a first data line, and a second data line. a common electrode electrically connected to the third electrode; a first data line electrically coupled to the first electrode to be configured to apply the first data voltage signal to the first electrode; and a second data line and the first The two electrodes are electrically connected to be configured to apply the second data voltage signal to the second electrode.

For example, in a pixel structure provided by an embodiment of the present disclosure, the second waveguide includes: a first outer layer, a second outer layer, and a third outer layer; and the second outer layer is opposite to the first outer layer An intermediate layer disposed between the first outer layer and the second outer layer; a material having a refractive index greater than a refractive index of the material of the first outer layer and the second outer layer The refractive index of the material; one of the plurality of color lights entering the middle of the second waveguide via the first waveguide.

For example, in a pixel structure provided by an embodiment of the present disclosure, a first layer of the second waveguide includes a plurality of total reflection subtractive structures, and the plurality of total reflection subtractive structures are configured to be conducted to the second waveguide The colored light in the second layer exits through the plurality of total reflection subtracting structures.

For example, in a pixel structure provided by an embodiment of the present disclosure, the plurality of total reflection subtractive structures are a plurality of grooves distributed in a dot shape.

At least one embodiment of the present disclosure further provides a display panel, which includes any of the pixel structures provided by the embodiments of the present disclosure.

For example, a display panel according to an embodiment of the present disclosure includes a pixel array including a plurality of pixel units; each of the plurality of pixel units includes a plurality of sub-pixel units, and the plurality of sub-pixel units Each of the pixel structures includes the pixel structures of the plurality of sub-pixel units respectively emitting light of different colors.

For example, a display panel according to an embodiment of the present disclosure further includes a backlight configured to emit light emitted to the beam splitting component in the sub-pixel unit.

For example, a display panel according to an embodiment of the present disclosure further includes a light guide plate configured to introduce light emitted by the backlight into the sub-pixel unit and into the curved grating.

At least one embodiment of the present disclosure further provides a display device including any display panel provided by an embodiment of the present disclosure.

At least one embodiment of the present disclosure further provides a display method, which is a method for operating a display device provided by an embodiment of the present disclosure, the method comprising: applying an electric field to the first waveguide; and changing the formation of the electric field by changing The phase of the electrical signal changes the refractive index of the first waveguide to control the gray scale of the pixel unit corresponding to the first waveguide.

DRAWINGS

In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the drawings of the embodiments will be briefly described below. It is obvious that the drawings in the following description relate only to some embodiments of the present disclosure, and are not to limit the disclosure. .

Figure 1A is a schematic view of a curved grating device;

1B is a schematic diagram of calculation of the optical path of the curved grating;

2A is a schematic view showing the structure and principle of a blazed grating;

2B is a schematic view of the situation before and after the diffraction zero-order spectral shift of the blazed grating;

FIG. 3 is a schematic structural diagram of a pixel according to an embodiment of the present disclosure;

4A is a cross-sectional view of a pixel structure taken along line I-I' of FIG. 3;

4B is a schematic view showing diffraction of a light beam incident on a planar grating;

4C is a partial enlarged view of the light-emitting surface of the curved blazed grating of FIG. 4A;

4D is another schematic cross-sectional view of the pixel structure taken along the line I-I' in FIG. 3;

FIG. 5 is a schematic diagram of changing a luminous flux through a first waveguide in a pixel structure according to an embodiment of the present disclosure;

Figure 6A is a schematic cross-sectional view taken along line G-G' in Figure 5;

Figure 6B is another schematic cross-sectional view taken along line G-G' in Figure 5;

Figure 6C is a schematic cross-sectional view along the line G-G' in Figure 5;

Figure 6D is a partial enlarged view of the light exit surface of the planar blazed grating of Figure 6C;

FIG. 7 is a schematic plan view of a display panel according to an embodiment of the present disclosure;

8 is a schematic plan view of a pixel unit of the display panel shown in FIG. 7;

Figure 9A is a schematic cross-sectional view taken along line H-H' in Figure 8;

Figure 9B is another schematic cross-sectional view taken along the line H-H' in Figure 8;

FIG. 10 is a schematic diagram of a display device according to an embodiment of the present disclosure.

Detailed ways

The technical solutions of the embodiments of the present invention will be clearly and completely described in the following with reference to the accompanying drawings. It is apparent that the described embodiments are part of the embodiments of the invention, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the described embodiments of the invention, without departing from the scope of the invention, are within the scope of the invention.

Unless otherwise defined, technical terms or scientific terms used herein shall be taken to mean the ordinary meaning of the ordinary skill in the art to which the invention pertains. The words "first", "second" and similar terms used in the specification and claims of the present invention do not denote any order, quantity, or importance, but are merely used to distinguish different components. The word "comprising" or "comprises" or the like means that the element or item preceding the word is intended to be in the "Inside", "outside", "upper", "lower", etc. are only used to indicate relative positional relationship, and when the absolute position of the object to be described is changed, the relative positional relationship may also change accordingly.

The dimensions of the drawings used in the present disclosure are not strictly drawn in actual scale, and the number of pixel units in the display panel is not limited to the number shown in the figure, and the specific size and number of each structure may be determined according to actual needs. . The drawings in the present disclosure are merely schematic structural views.

The principle of splitting the surface grating is first described below. FIG. 1A is a schematic diagram of a curved grating device, and FIG. 1B is a schematic diagram of calculation of an optical path of a curved grating. Curved gratings are usually made by scribing a series of equal-width equidistant scribe lines on a curved spherical mirror. Compared with planar gratings, surface gratings have both quasi-light and focusing effects in addition to diffraction. Therefore, grating spectra can be generated without adding other optical systems. 1A is a conventional curved grating device. As shown in FIG. 1A, the slit light source S, the curved grating G, and the image-bearing negative film N are all on the same circumference. The diameter of this circle is equal to the radius of curvature of the surface grating, which is often referred to as the Roland circle. Usually, the image is placed on the Roland circle to record the spectrum, because it is theoretically possible to prove that the light emitted by the slit source on the Roland circle is fused by the concave grating (the center of which is tangent to the Roland circle). They will all gather on the Roland Circle.

As shown in FIG. 1B, G _j , G _j+1 represent the position of two adjacent grating scribe lines, d is the grating constant of the curved grating, C is the center of the curved grating, S is the light source, and P is the position of the diffraction image. . The rays SG _j and SG _j+1 of wavelength λ emitted by S are diffracted by the curved grating and focused on point P. The position of the P point satisfies the condition that the light intensity is extremely large. Let SE = SG _j , PF = PG _j , and according to the diffraction maximum condition, the optical path difference of the two beams of light incident on the adjacent two reticle wavelengths is λ is an integer multiple of the wavelength:

Kλ=(SG _j +G _j P)-(SG _j +1+G _j+1 P)

=(SE+FP)-(SG _j+1 +G _j+1 P)

=G _j+1 E+G _j+1 F

=G _j G _j+1 sinα+G _j G _j+1 sinβ

=d(sinα+sinβ)

That is, the grating equation kλ=d(sinα+sinβ) of the curved grating is obtained (k=0, ±1, ±2...), where k is the series. According to the above grating equation, each level of the spectrum has a certain position, and the image-forming film can be placed on the corresponding circumference according to the required wavelength band.

The specifics of the blazed grating are described below. 2A is a schematic diagram showing the structure and principle of a blazed grating, and FIG. 2B is a schematic diagram of the front and back of the diffraction zero-order spectrum of the blazed grating. As shown in Figure 2A, the blazed grating is typically a reflective grating. The grooved surface of the blazed grating is not parallel to the grating surface, and has an angle γ therebetween, which can greatly separate the zero-order main maximum of the single groove surface diffraction from the zero-order main body of the interference generated between the plurality of groove surfaces. Thereby, the light energy is greatly transferred from the interference zero-order main and concentrated to a certain level of the spectrum. Taking light with an incident angle of i=γ (that is, perpendicular to the groove surface) and a wavelength of λ as an example, the first-order spectrum of the wavelength λ greatly coincides with the zero-order main of the single-slot diffraction, and this level of spectrum will obtain the largest. brightness. And because the groove width a ≈ d of the blazed grating, the spectrum of other orders of the wavelength λ (including the zero order) almost coincides with the minimum position of the diffraction of the single groove surface, so that the intensity of these orders of the spectrum is small, and Most of the energy is transferred and concentrated on the level 1 spectrum. Therefore, by using the blazed grating, the diffraction zero-order spectrum can be moved to the position of the interference level 1 spectrum, as shown in FIG. 2B, thereby performing the splitting, thereby making full use of the energy of the diffraction zero-order spectrum.

At least one embodiment of the present disclosure provides a pixel structure including: a pixel region, a non-pixel region located on one side of the pixel region, a curved grating, a first waveguide, and a second waveguide. The curved grating is located in the non-pixel region and is configured to disperse light into a plurality of color lights; the first waveguide is located in the non-pixel region; and the second waveguide is located in the pixel region. The first waveguide includes a first end adjacent to the pixel region, the second waveguide includes a first end adjacent to the non-pixel region, and the first end of the first waveguide is coupled to the first end of the second waveguide; the first waveguide is configured to be One of the colored lights is conducted into the second waveguide, and the second waveguide is configured to emit the colored light transmitted thereto at a predetermined position.

Illustratively, FIG. 3 is a schematic diagram of a pixel structure according to an embodiment of the present disclosure, and FIG. 4A is a cross-sectional view of the pixel structure along the line I-I' in FIG. FIG. 5 is a schematic diagram of changing the luminous flux through the first waveguide in a pixel structure shown in FIGS. 3 and 4A. For example, each sub-pixel unit of a pixel array according to an embodiment of the present disclosure adopts the pixel structure.

3 and 4A, the pixel structure 10 includes a pixel region 101, a non-pixel region 102 on one side of the pixel region 101, a spectroscopic component 100, a first waveguide 2, and a second waveguide 3. The beam splitting assembly 100 is located in the non-pixel region 102 and is capable of receiving incident light from the light source S and dispersing the incident light into a plurality of color lights, such as primary color light, for example, the plurality of color lights including red light, green light or blue light. The first waveguide 2 is located in the non-pixel region 102, and the second waveguide 3 is located at least in the pixel region 101. For example, in FIG. 4A, the entire second waveguide 3 is located in the pixel region 101. For example, in other embodiments, a portion of the second waveguide 3 can be located within the non-pixel region 102. The first waveguide 2 includes a first end 21 adjacent to the pixel region 101, and the second waveguide 3 includes a first end 31 adjacent to the non-pixel region 102, the first end 21 of the first waveguide 2 and the first end 31 of the second waveguide 3 connection. By properly designing the position of the first waveguide 2, the first waveguide 2 can receive one of the plurality of color lights obtained after being split by the beam splitting assembly 100, and conduct one of the received plurality of color lights to the second waveguide 3. in. Light incident into the second waveguide 3 is conducted to respective positions of the pixel region via the second waveguide 3, and the second waveguide 3 is disposed to be capable of emitting color light guided thereto at a predetermined position, thereby realizing a display function of the pixel structure.

It should be noted that the predetermined position is a light-emitting area designed on the light-emitting side of the pixel area according to actual requirements, for example, an exit point arranged in an array.

For example, the beam splitting assembly 100 includes a curved grating 1. As shown in FIG. 3 and FIG. 4A, the first waveguide 2 is capable of receiving one of a plurality of color lights obtained after being split by the curved grating 1, and transmitting one of the received plurality of color lights to the second waveguide 3. Thereby achieving display. Compared with the use of a planar grating (for example, a planar sinusoidal grating), the curved grating used in the pixel structure has a collecting effect, which can improve the utilization efficiency of light and is advantageous for achieving a better display effect. Moreover, the structure of the pixel structure is simple, and it is not necessary to provide, for example, a liquid crystal layer to realize a light valve function, which is advantageous for realizing a thin display device.

For example, as shown in FIG. 4A, the light-emitting surface 103 of the curved grating 1 is a concave surface that faces the first waveguide 2. The first waveguide 2 further includes a second end 22 remote from the pixel region 101, and one of a plurality of color lights dispersed via the curved grating 1 is incident through the concave surface to the second end 22 of the first waveguide 2 to cause one of the plurality of color lights to be incident Into the first waveguide 2. For example, the curved grating 1 is a Roland circular grating. According to the spectroscopic principle of the above-mentioned curved grating, the position of each spectrum of the desired wavelength is determined according to the grating equation and the required wavelength band, for example, a higher-order first-order spectrum can be selected. The light incident surface of the first waveguide 2 near the first end of the curved grating may be disposed on a corresponding circumference of the Roland circle of the curved grating. The light of the desired wavelength may be light of a desired wavelength, and may be, for example, any of red, green, and blue light.

In addition, the curved grating can have a larger spectroscopic wavelength range relative to the planar grating. Fig. 4B is a schematic view showing diffraction of a light beam incident on a planar grating. As shown in Figure 4B, the grating equation can usually be expressed as:

Kλ=d(sini+sinθ)(k=0,±1,±2...) (1)

In the formula (1), k is a series, i is an incident angle, θ is a diffraction angle, and λ is a wavelength of incident light. For example, light from the light source enters the pixel structure through the light guide plate. When light from the light guide plate is incident on the grating in parallel, for example, light from the light guide plate is collimated light, and is incident perpendicularly to the grating, then i=0, sini=0 Therefore, λ ≤ d / k, that is, the wavelength range in which the planar grating can achieve the splitting is λ ≤ d / k. In this case, when the same light is incident on the curved grating, since the sini + sin θ ≤ 2, the surface grating can achieve the wavelength range of λ ≤ 2d / k. Therefore, the curved grating can have a larger spectral range with respect to the planar grating, enabling a higher color gamut.

For example, the curved grating 1 is a reflective grating configured to enter and exit light from the same side of the curved grating 1. For example, incident light is incident from the light-emitting surface 103 side of the curved grating 1, and is reflected and emitted from the light-emitting surface 103 side. That is, the light incident side and the light exiting side of the reflective grating are the same side. When a transmissive curved grating is used, the loss of light is large during transmission. Compared with the transmission type curved grating, when the reflective curved grating is used, the loss of light is small, so that the utilization of light can be further improved, the energy consumption is reduced, and a better display effect is achieved.

For example, in one embodiment, the curved grating 1 may be a curved blazed grating, and the illuminating surface of the blazed grating includes a grating surface having a curved surface and a concave-convex structure on the grating surface. 4C is a partial enlarged view of the light exit surface of the blazed grating of FIG. 4A. As shown in FIG. 4C, the light-emitting surface 103 of the curved grating 1 has the concave-convex structure 1031 of the surface of the blazed grating, that is, the curved grating 1 is a curved blazed grating, which realizes the combination of the curved grating and the planar blazed grating, which is equivalent to the usual planar blazed grating. Bend at the same curvature. The light-emitting surface 103 includes a curved surface 1033 and a concave-convex structure 1031. The concave-convex structure 1031 includes a groove surface 1032 having an angle γ with a tangent to the grating surface 1033. Generally, for a sinusoidal grating, the diffraction zero-order main maximum and the interference zero-order main maximum position are coincident, and the splitting cannot be achieved, while the diffraction zero-order main maximum and the interference zero-order main maximum light power are the highest, and the light energy is the highest. The loss is greater. According to the structure and principle of the above blazed grating, the curved grating 1 is designed as a blazed grating, and the diffraction zero-order spectrum can be moved to the position of the interference level 1 spectrum to realize the splitting, thereby making full use of the higher energy of the diffraction zero-order spectrum, and further Improve the light utilization of the pixel structure.

For example, in the pixel structure shown in FIGS. 3 and 4A, the first waveguide 2 includes a first portion 201 and a second portion 202 in parallel, an end of the first portion 201 of the first waveguide 2 remote from the pixel region 101 and the first waveguide An end of the second portion 202 of the second portion 202 remote from the pixel region 101 is connected, and an end of the first portion 201 of the first waveguide 2 adjacent to the pixel region 101 is connected to an end of the second portion 202 of the first waveguide 2 adjacent to the pixel region 101. For example, referring to FIG. 5, the light incident end C of the first waveguide 2 receives color light from a curved grating, and the color light is split into two light beams, namely, a light beam A and a light beam B, respectively, via the first portion 201 of the first waveguide 2, respectively. The second portion 202 of the first waveguide 2 is conducted, and the two beams are combined to form a light beam at the light exit end D of the first waveguide 2.

For example, the intensity of the light emitted through the light-emitting end D of the first waveguide 2 and the control light flux can be controlled by controlling the interference between the light beam A and the light beam B, thereby realizing the display gray scale of the pixel region, that is, the brightness of the light exiting. Referring to FIGS. 3, 4A and 5, for example, the pixel structure 10 further includes a first electrode 801, a second electrode 802, and a third electrode 803. The first electrode 801 and the third electrode 803 are configured to apply a first electric field to the first portion 201 of the first waveguide 2 located therebetween according to the first data voltage signal. The second electrode 802 and the third electrode 803 are configured to apply a second electric field to the second portion 202 of the first waveguide 2 located therebetween in accordance with the second data voltage signal. For example, referring to FIG. 3, for the pixel structure 10, a common electrode 5, a first data line 601, and a second data line 602 are also provided to provide a common voltage, a first data voltage, and a second data voltage, respectively. For example, the common electrode 5 is coupled to a common voltage terminal to obtain a common voltage signal, and the first data line 601 and the second data line 602 are coupled to the data driving circuit to obtain a first data voltage signal and a second data voltage signal. The common electrode 5 is electrically connected to the third electrode 803 to provide a common voltage signal to the third electrode 803; the first data line 601 is electrically connected to the first electrode 801 to provide a first data voltage signal to the first electrode 801; The data line 602 is electrically coupled to the second electrode 803 to provide a second data voltage signal to the second electrode 802. The superposition of the beam A and the beam B at the light-emitting end D of the first waveguide 2 corresponds to the superposition of two monochromatic light waves. When the phases of the first data voltage signal and the second data voltage signal are changed, the refractive index of the first portion 201 of the first waveguide 2 and the second portion 202 of the first waveguide 2 may be changed. The phase of the first data voltage signal and the second data voltage signal may be controlled to be different such that the refractive indices of the first portion 201 of the first waveguide 2 and the second portion 202 of the first waveguide 2 become different, thereby causing the beam A and the beam B produces an optical path difference. Therefore, when the beam A and the beam B reach the light-emitting end D of the first waveguide 2, the phases of the two are different, and there is a phase difference. For example, if the amplitudes of the beam A and the beam B are equal, according to the superposition principle, the light intensity I after the superposition of the beam A and the beam B is:

I=4I ₀ cos ² (δ/2) (2)

In the formula (2), I ₀ is the light intensity of a single beam, and δ is the phase difference when the two light waves reach the light-emitting end D of the first waveguide 2 and are superimposed. It can be seen from the formula (2) that the light intensity after superposition is determined by the phase difference δ. When δ=±2mπ (m=0, 1, 2...), I=4I ₀ , the superposed light intensity is the strongest, that is, the light intensity of the second waveguide 3 incident to the pixel region through the first waveguide 2 is the strongest; When δ=±(m+1/2)2π(m=0,1,2...), I=0, the light intensity after superposition is the weakest, and the luminous flux is zero, that is, no light is incident on the pixel through the first waveguide 2. a region, thereby realizing a dark state display; when the phase difference δ is between the above-mentioned value that makes the light intensity strongest and the value that makes the light intensity the weakest, the superimposed light intensity is between the minimum and maximum values of the light intensity between. Therefore, the light flux conducted to the pixel region via the first waveguide can be controlled by controlling the phases of the first data voltage signal and the second data voltage signal, thereby controlling the display gray scale.

For example, Fig. 6A is a schematic cross-sectional view taken along line G-G' in Fig. 5. As shown in FIG. 6A, the first waveguide 2 includes a first layer 2001, a second layer 2002, and a waveguide layer 2003. The second layer 2002 of the first waveguide 2 is disposed on the first layer 2001 of the first waveguide 2. The waveguide layer 2003 of the first waveguide 2 is disposed between the first layer 2001 of the first waveguide 2 and the second layer of the first waveguide 2. The refractive index of the material of the waveguide layer 2003 of the first waveguide 2 is greater than the refractive index of the material of the first layer 2001 of the first waveguide 2 and the refractive index of the material of the second layer 2002 of the first waveguide 2, so that the incident to the first The colored light in the waveguide layer 2002 of a waveguide 2 is totally reflected to the second waveguide 3 in the waveguide layer 2002 of the first waveguide 2.

For example, the material of the waveguide layer 2003 of the first waveguide 2 is an electro-index change material. For example, the electrorefractive index changing material may be an inorganic electrorefractive index changing material or an organic electrorefractive index changing material. The electroless refractive index change material may be, for example, tungsten trioxide (WO ₃ ), titanium oxide (TiO ₂ ), molybdenum trioxide (MoO ₃ ), vanadium pentoxide (V ₂ O ₅ ), nickel oxide (NiO), or the like. The organic electro-refractive index-changing material may be, for example, a viologen compound, a tetrathiafulvalene or a metal phthalocyanine compound, or the like, or a conductive polymer electro-refractive index-changing material such as polythiophene and a derivative thereof, Conductive polyacetylene and the like. For example, the material of the first layer 2001 of the first waveguide 2 and the second layer 2002 of the first waveguide 2 may be a low refractive index material magnesium fluoride, porous silica or fluorosilicon oxide or the like. Of course, the material of the waveguide layer of the first waveguide is not limited to the above-listed types, and the embodiment of the present disclosure does not limit this.

It should be noted that, in other embodiments of the present disclosure, the first waveguide may not be a three-layer structure. For example, the first waveguide may comprise an inner layer and an outer layer encasing the inner layer, ie a fiber-like structure. The refractive index of the material of the inner layer is greater than the refractive index of the material of the outer layer. The material of the inner layer is, for example, the above-described electrorefractive index changing material.

For example, as shown in FIG. 4A, the second waveguide 3 includes a first outer layer 301, a second outer layer 302, and an intermediate layer 303. The second outer layer 302 is opposite the first outer layer 301; the intermediate layer 303 is disposed between the first outer layer 301 and the second outer layer 302. Also, the refractive index of the material of the intermediate layer 303 is greater than the refractive index of the material of the first outer layer 301 and the refractive index of the material of the second outer layer 302. Thus, the color light conducted in the first waveguide 2 enters the intermediate layer 303 and can be conducted in the intermediate layer 303 in the form of total reflection to various positions of the pixel region.

For example, the first outer layer 301 includes a plurality of total reflection abatement structures 12 disposed at different locations. The plurality of total reflection subtractive structures 12 are configured to emit colored light that is conducted into the intermediate layer 303 via the plurality of total reflection subtracting structures 12. For example, the predetermined position described above is the position at which the total reflection reducing structure 12 is disposed. For example, the plurality of total reflection subtracting structures may be a plurality of grooves distributed in a dot shape. These grooves are disposed at the interface between the intermediate layer 303 and the first outer layer 301, such that the incident angle of light incident on the interface can be changed, destroying the total reflection condition, thereby causing at least partial incidence to the grooves. Light exits from the intermediate layer 303 to the first outer layer 301, and then exits from the first outer layer 301, thereby effecting display. Of course, the total reflection mitigation structure may also be a structure other than the groove, for example, it may be a bump, a light-receiving grating, etc., and the embodiment of the present disclosure does not limit this.

It should be noted that the color light entering the first waveguide after being split by the curved grating may be any wavelength of light, and may be any one of red, green, and blue light, for example. Illustratively, for example, the color light is red light, and the pixel area of the pixel structure displays a red color.

For example, as shown in FIG. 3, the first waveguide 2 further includes a third portion 203, and the third portion 203 of the first waveguide 2 is in direct contact with the second waveguide 3 near the first end 31 of the second waveguide 3 to reduce light loss. And, the width of the first end 31 of the first waveguide 2 is substantially equal to the width L of the second waveguide 3. In this way, the color light conducted in the first waveguide 2 can be more directly transmitted to the respective positions of the first end 31 of the second waveguide 3, thereby being more directly transmitted to the respective positions of the pixel region 101, which is advantageous for reducing the path of the colored light. Improve the efficiency of light utilization.

For example, in another embodiment, the first portion 201 of the first waveguide 2 and the second portion 202 of the first waveguide 2 may comprise a Bragg-type diffraction grating. Figure 6B is a schematic illustration of another first waveguide. As shown in FIG. 6B, for example, the first waveguide may include an inner layer and an outer layer 18 encasing the inner layer, ie, an optical fiber-like structure. The refractive index of the material of the inner layer of the first waveguide is greater than the refractive index of the material of the outer layer 18 of the first waveguide. The material of the inner layer of the first waveguide is, for example, the above-described electrorefractive index changing material. For example, the inner layer 17 of the first waveguide is a Bragg-type grating. The Bragg-type grating has a periodically varying refractive index in a direction from the non-pixel region 102 to the pixel region 101, and the period is T. One period T of the Bragg-type grating includes a first portion 1701 and a second portion 1702 having different refractive indices. By designing the parameters of the Bragg grating, such parameters include, for example, the first portion 1701 of one period of the Bragg grating and the refractive index of the second portion 1702 of one period of the Bragg grating, the first portion 1701 of one period of the Bragg grating, and one period of the Bragg grating The width of the second portion 1702, etc., can be designed as needed by those skilled in the art. The desired color light can be transmitted through the Bragg grating to the second waveguide 3 of the pixel structure 10. The use of the Bragg grating to selectively color light enables narrowing of the band edge of the color light entering the second waveguide 3, thereby facilitating the improvement of the color gamut of the display.

Figure 4D is a cross-sectional view of another pixel structure taken along line I-I' of Figure 3. As shown in FIG. 4D, the pixel structure 10 differs from the pixel structure shown in FIG. 4A in that it further includes a reflective structure 4. The light exit surface 103 of the curved grating 1 is a concave surface facing the reflective structure 4, and the reflective structure 4 is configured to reflect one of the plurality of color lights dispersed through the curved grating 1 to the second end of the first waveguide 2 away from the pixel region 101. 22 such that one of the plurality of color lights is incident into the first waveguide 2. The reflective structure 4 can be, for example, a reflective sheet. For example, the reflecting surface of the reflective structure 4 facing the curved grating 1 is concave, so as to have a collecting effect, which is advantageous for improving the utilization of light. The other structure of the pixel structure shown in FIG. 4D is the same as that shown in FIG. 4A, please refer to the above description.

Fig. 6C is another schematic cross-sectional view taken along the line G-G' in Fig. 5. In another implementation of the present disclosure, for example, as shown in FIG. 6C, the first waveguide 2 further includes a second end 21 away from the pixel region 101; the beam splitting assembly 100 includes a planar grating 20 and a lens 30, the planar grating 20 being configured to be incident The light is dispersed into a plurality of color lights, and the lens 30 is configured to adjust the plurality of color lights such that one of the plurality of color lights dispersed via the planar grating 20 is emitted through the lens 30 and then incident on the second end 22 of the first waveguide 2 to One of a plurality of color lights is incident into the first waveguide 2. For example, lens 30 is an optical lens that enables quasi-light and focusing of multiple color lights, and those skilled in the art can select a suitable lens 30 based on the spectrum produced by the planar grating selected. The embodiment shown in Fig. 6C can achieve the same or similar technical effects as the previously described embodiments, please refer to the previous description.

For example, in the embodiment illustrated in Figure 6C, the planar grating 20 includes a planar blazed grating, such as at least a portion of the planar grating 20 being a planar blazed grating. Figure 6D is a partial enlarged view of the light exit surface of the planar blazed grating of Figure 6C. As shown in FIG. 6D, a portion of the light-emitting surface 200 of the planar grating 20 has a concave-convex structure of the surface of the blazed grating, and the concave-convex structure includes a groove surface having an angle γ with the grating surface. Generally, for a sinusoidal grating, the diffraction zero-order main maximum and the interference zero-order main maximum position are coincident, and the splitting cannot be achieved, while the diffraction zero-order main maximum and the interference zero-order main maximum light power are the highest, and the light energy is the highest. The loss is greater. It can be known from the structure and principle of the above blazed grating that at least part of the planar grating 20 is designed as a blazed grating to enable the diffraction zero-order spectrum to move to the position of the interference level 1 spectrum to realize the splitting, thereby making full use of the higher energy of the diffraction zero-order spectrum. , can further improve the light utilization efficiency of the pixel structure.

An embodiment of the present disclosure further provides a display panel, which includes any of the pixel structures provided by the embodiments of the present disclosure. The display panel provided by the embodiment of the present disclosure has a simple structure, and it is not necessary to provide, for example, a liquid crystal layer to realize a light valve function, which is advantageous for thinning of the display panel. Moreover, the display panel of this embodiment has higher light utilization efficiency, correspondingly consumes less energy, and has a better energy efficiency ratio than a display panel using a planar grating.

FIG. 7 is a schematic plan view of a display panel according to an embodiment of the present disclosure. As shown in FIG. 7, the display panel 15 includes a pixel array including a plurality of pixel units 14 arranged in an array. FIG. 8 is a plan view showing a pixel unit 14 of the display panel 15 shown in FIG. As shown in FIG. 8 , for example, each of the plurality of pixel units 14 includes a plurality of sub-pixel units, each of the plurality of sub-pixel units including any one of the pixel structures provided by the embodiments of the present disclosure. The pixel structure respectively emits light of different colors. For example, the different colored lights can be combined to form white light. For example, each pixel unit 14 includes three sub-pixel units, which are a first sub-pixel unit 901, a second sub-pixel unit 902, and a third sub-pixel unit 903, respectively, a first sub-pixel unit 901, a second sub-pixel unit 902, and The pixel structures in the third sub-pixel unit 903 respectively emit light of different colors. For example, the first sub-pixel unit 901 is a red sub-pixel unit, wherein a pixel region of the pixel structure emits red light; the second sub-pixel unit 902 is a green sub-pixel unit, wherein a pixel region of the pixel structure emits green light; The sub-pixel unit 903 is a blue sub-pixel unit in which a pixel region of the pixel structure emits blue light. In this way, the light of these different colors is combined to obtain a plurality of colors required for display, whereby the display panel 15 can realize color display.

As shown in FIG. 8, in this embodiment, the three sub-pixel units 901/902/903 of each pixel unit 14 share the same common electrode 5, for example, can be respectively connected to different first data lines 601 and second data. Line 602 is further coupled to the data drive circuit to receive the respective first data voltage signal and second data voltage signal during operation.

Fig. 9A is a schematic cross-sectional view taken along line H-H' of Fig. 8. As shown in FIG. 8 and FIG. 9A , the display panel 15 includes a first substrate 701 and a second substrate 702 opposite to the first substrate 701 . The pixel structure is located between the first substrate 701 and the second substrate 702. The first waveguide 2, the first electrode 801, the second electrode 802, and the third electrode 803 are disposed on a side of the first substrate 701 facing the second substrate 702, and the second waveguide 3 is located on the first substrate 701 and the second substrate 702. between. The curved grating 1 is disposed on a side of the second substrate 702 facing the first substrate 701.

Fig. 9B is another schematic cross-sectional view taken along the line H-H' in Fig. 8. As shown in FIGS. 8 and 9B, the pixel structure is located between the first substrate 701 and the second substrate 702. The curved grating 1, the first waveguide 2, the first electrode 801, the second electrode 802, and the third electrode 803 are disposed on a side of the first substrate 701 facing the second substrate 702, and the reflective structure 4 is located on the surface of the second substrate 702. One side of the first substrate 701. For example, a light transmissive layer 19 is disposed between the second substrate 702 and the first waveguide 2 to have a suitable distance between the first waveguide 2 and the second substrate 702 as needed. The second waveguide 3 is located between the first substrate 701 and the second substrate 702.

For example, the display panel 15 further includes a backlight 11 that is, for example, a surface light source, and is configured such that the emitted incident light is incident on the spectroscopic component 1 in the sub-pixel unit at a specific position. For example, when the display panel 15 includes the pixel structure as shown in FIG. 4A, incident light from the light source is incident to the curved grating 1 in the sub-pixel unit at a specific position. For example, when the display panel 15 includes a pixel structure as shown in FIG. 6C, incident light from the light source is incident on the planar grating 20 in the sub-pixel unit at a specific position.

For example, the display panel 15 further includes a light guide plate 13. The light incident surface of the light guide plate 13 faces the light exit surface of the backlight 11, and the light emitted by the backlight 11 is conducted in the light guide plate 11 in the form of total reflection. A second total reflection subtracting structure 19 is disposed on the light-emitting surface of the light guide plate, and the second total reflection subtracting structure 19 is located at a position corresponding to the light-splitting structure 100 of each sub-pixel unit to destroy the total reflection condition, so that the light is in the total reflection subtracting structure 19 The position is emitted to enter each sub-pixel unit and is incident on the curved grating 1. The total reflection reducing structure 19 may be, for example, a groove or a rib located on the interface between the light-emitting surface of the light guide plate 13 and the second substrate 702. 9A and 9B illustrate the first sub-pixel unit 901 as an example. It should be noted that the backlights in FIG. 9A and FIG. 9B are side-entry light sources. In other examples, a direct-type light source may be disposed at a position corresponding to the curved grating of each sub-pixel unit, and the direct-type light source may be matched with the light guide plate. Light is incident on the curved grating without being incident on other locations of the pixel unit.

An embodiment of the present disclosure further provides a display device, which includes any display panel provided by an embodiment of the present disclosure. FIG. 10 is a schematic diagram of a display device according to an embodiment of the present disclosure. As shown in FIG. 10, the display device 16 includes a display panel 15, which is any display panel provided by the embodiments of the present disclosure. The display device 16 may further include other components and circuits and the like that cooperate with the display panel 15 to implement a display function, such as a power supply circuit, a data driving circuit, a signal decoding circuit, a controller, etc., and these components and circuits may be implemented in a conventional manner. The disclosed embodiments do not limit this. The display device 16 can be, for example, a mobile phone, a tablet computer, a television, a display, a notebook computer, a digital photo frame, a navigator, or the like, with any display product or component. The display device provided by the embodiment of the present disclosure has a simple structure, and it is not necessary to provide, for example, a liquid crystal layer to realize a light valve function, which is advantageous for thinning of the display device. Moreover, compared with a display device using a planar grating, the display panel has a higher light utilization rate, correspondingly consumes less energy, and has a better energy efficiency ratio.

An embodiment of the present disclosure further provides a display method, which is a method for operating a display device provided by an embodiment of the present disclosure, the method comprising: applying an electric field to a first waveguide by changing an electrical signal forming the electric field The phase changes the refractive index of the first waveguide to control the gray scale of the pixel unit corresponding to the first waveguide.

For example, the description will be made by taking each pixel unit of the display device including the pixel structure shown in FIGS. 3 and 4A as an example. Light emitted from the backlight is incident on the curved grating 1 via the light guide plate. For example, in each pixel unit, the color light that is incident on the first waveguide 2 after being split by the curved grating 1 in the first sub-pixel unit is red light, and the second sub-pixel unit is split by the curved grating 1 and then incident on the first waveguide. The color light of 2 is green light, and the color light that is incident on the first waveguide 2 through the curved grating 1 in the third sub-pixel unit is blue light. The first sub-pixel unit will be described below as an example. As shown in FIG. 5, in the first sub-pixel unit, the light incident end C of the first waveguide receives red light from the curved grating, and the red light is split into two light beams: a light beam A and a light beam B, respectively. The first portion 201 of the first waveguide 2 and the second portion 202 of the first waveguide 2 are conducted, and the two beams combine to form a light beam at the light exit end D of the first waveguide 2.

For example, the intensity of light emitted through the light-emitting end D of the first waveguide 2 can be controlled by controlling the interference between the light beam A and the light beam B, and the light flux can be controlled, thereby realizing the display gray scale of the pixel region. Referring to FIG. 3, FIG. 4A and FIG. 5, a common voltage signal is supplied to the third electrode 803 through the common electrode 5, a first data voltage signal is supplied to the first electrode 801 through the first data line 601, and a first data voltage signal is supplied through the second data line 602. The second electrode 802 provides a second data voltage signal. The superposition of the beam A and the beam B at the light-emitting end D of the first waveguide 2 corresponds to the superposition of two monochromatic light waves. When the phases of the first data voltage signal and the second data voltage signal are changed, the refractive index of the first portion 201 of the first waveguide 2 and the second portion 202 of the first waveguide 2 can be changed. The phase of the first data voltage signal and the second data voltage signal may be controlled to be different such that the refractive indices of the first portion 201 of the first waveguide 2 and the second portion 202 of the first waveguide 2 become different, thereby causing the beam A and the beam B produces an optical path difference. Therefore, when the beam A and the beam B reach the light-emitting end D of the first waveguide 2, the phases of the two are different, and there is a phase difference. According to the above-described monochromatic light superposition principle, the amount of red light conducted to the pixel region via the first waveguide can be controlled by controlling the phases of the first data voltage signal and the second data voltage signal. Similarly, in the second sub-pixel unit and the third sub-pixel unit, the amount of green light and blue light conducted to the pixel region via the first waveguide can be separately controlled by the same method. Thereby, the display gray scale of the display unit can be controlled. By controlling the color display state of the display device of each display unit.

The above is only an exemplary embodiment of the present invention, and is not intended to limit the scope of the present invention. The scope of the present invention is defined by the appended claims.

Claims (24)

A pixel structure comprising: a pixel region and a non-pixel region located on one side of the pixel region; a light splitting component, located in the non-pixel area and configured to disperse incident light into a plurality of color lights; a first waveguide located in the non-pixel region; a second waveguide located in the pixel area; Wherein the first waveguide includes a first end adjacent to the pixel region, the second waveguide includes a first end adjacent to the non-pixel region, a first end of the first waveguide and the second waveguide a first end connection; the first waveguide configured to receive one of the plurality of color lights from the beam splitting component and to conduct one of the plurality of color lights into the second waveguide, the second waveguide configuration And emitting one of the plurality of color lights conducted into the second waveguide at a predetermined position. The pixel structure of claim 1 wherein said beam splitting component comprises a curved grating. The pixel structure according to claim 2, wherein a light exit surface of the curved grating is a concave surface, the concave surface faces the first waveguide; and the first waveguide further includes a second end away from the pixel region, via One of the plurality of color lights dispersed by the curved grating is emitted through the concave surface and then incident on the second end of the first waveguide such that one of the plurality of color lights is incident into the first waveguide. The pixel structure according to claim 2, further comprising a reflective structure; wherein a light exiting surface of the curved grating is a concave surface, the concave surface facing the reflective structure; and the first waveguide further comprises a distance away from the pixel region At both ends, the reflective structure is configured to reflect one of a plurality of color lights dispersed through the curved grating and emitted through the concave surface to a second end of the first waveguide to cause one of the plurality of color lights Incident into the first waveguide. The pixel structure according to any one of claims 2 to 4, wherein the curved grating is a reflective grating configured to enter and exit light from the same side of the curved grating. A pixel structure according to any of claims 2-5, wherein the curved grating is a Roland circular grating. The pixel structure according to any one of claims 2-6, wherein at least part of the curved grating is a curved blazed grating, and a light-emitting surface of the curved blazed grating comprises a grating surface having a curved surface and a grating surface located on the grating surface a concave-convex structure; the concave-convex structure includes a groove surface having an angle with a tangent of the grating surface. The pixel structure of claim 1 wherein said first waveguide further comprises a second end remote from said pixel region; The beam splitting assembly includes a planar grating configured to disperse incident light into a plurality of colored lights, and a lens configured to adjust the plurality of colored lights to be dispersed by the planar grating One of the colored lights is emitted through the lens and then incident on the second end of the first waveguide such that one of the plurality of colored lights is incident into the first waveguide. The pixel structure of claim 8 wherein said planar grating comprises a planar blazed grating. A pixel structure according to any of claims 1-9, wherein said first waveguide comprises a first portion and a second portion in parallel, One end of the first portion remote from the pixel region and one end of the second portion remote from the pixel region are connected, and an end of the first portion adjacent to the pixel region and the second portion are adjacent to the One end of the pixel area is connected. The pixel structure of any of claims 1-10, wherein the first waveguide comprises: level one; a second layer disposed on the first layer; a waveguide layer disposed between the first layer and the second layer; Wherein the refractive index of the material of the waveguide layer is greater than the refractive index of the material of the first layer and the refractive index of the material of the second layer; One of the plurality of color lights is conducted to the second waveguide via total reflection at the waveguide layer. The pixel structure according to claim 11, wherein the material of the waveguide layer is an electro-refractive index changing material. The pixel structure according to any one of claims 1 to 11, wherein said first waveguide comprises a Bragg-type diffraction grating, said Bragg-type grating having a direction along a direction from said non-pixel region to said pixel region The refractive index of the period changes. The pixel structure according to any one of claims 10-13, further comprising a first electrode, a second electrode, and a third electrode, wherein The first electrode and the third electrode are configured to apply a first electric field to the first portion of the first waveguide according to the first data voltage signal; The second electrode and the third electrode are configured to apply a second electric field to the second portion of the first waveguide in accordance with a second data voltage signal. The pixel structure of claim 14, further comprising: a common electrode electrically connected to the third electrode; a first data line electrically coupled to the first electrode to be configured to apply the first data voltage signal to the first electrode; a second data line electrically coupled to the second electrode to be configured to apply the second data voltage signal to the second electrode. The pixel structure of any of claims 1-15, wherein the second waveguide comprises: First outer layer; a second outer layer opposite the first outer layer; An intermediate layer disposed between the first outer layer and the second outer layer; Wherein the refractive index of the material of the intermediate layer is greater than the refractive index of the material of the first outer layer and the refractive index of the material of the second outer layer; One of the plurality of color lights enters the middle of the second waveguide via the first waveguide. The pixel structure of claim 16 wherein the first layer of the second waveguide comprises a plurality of total reflection subtractive structures configured to conduct a third to the second waveguide The colored light in the layer exits through the plurality of total reflection subtractive structures. The pixel structure according to claim 17, wherein the plurality of total reflection subtracting structures are a plurality of grooves distributed in a dot shape. A display panel comprising the plurality of pixel structures of any of claims 1-18. The display panel of claim 19, comprising: a pixel array comprising a plurality of pixel units; Wherein each of the plurality of pixel units includes a plurality of sub-pixel units, each of the plurality of sub-pixel units including the pixel structure, the pixel structures in the plurality of sub-pixel units respectively emitting different colors Light. The display panel according to claim 19 or 20, further comprising: a backlight configured to emit light emitted to the beam splitting component in the sub-pixel unit. The display panel according to any one of claims 19-21, further comprising: a light guide plate configured to introduce light emitted by the backlight into the sub-pixel unit and incident on the beam splitting assembly. A display device comprising the display panel of any of claims 19-22. A display method, applicable to the method of operating the display device of claim 23, comprising: Applying an electric field to the first waveguide; The refractive index of the first waveguide is changed by changing the phase of the electrical signal forming the electric field to control the gray scale of the pixel unit corresponding to the first waveguide.

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