TWI720883B - An electroluminescent display - Google Patents

Abstract

An electroluminescent display is provided. The electroluminescent display comprises an electroluminescent panel, a color improvement film attached to a light exit surface of the electroluminescent panel, and a circular polarizer attached to a surface of the color improvement film. The color improvement film includes, in order from the side of the circular polarizer, a substrate, a first strip-shaped micro-prism layer, and a first filling layer. The first strip-shaped micro-prism layer has a first refractive index n1 and includes a plurality of first strip-shaped micro-prisms arranged in a first direction formed on the substrate, and each of the first strip-shaped micro-prisms has at least one first inclined light-guide surface, and the first inclined light-guide surface has an included angle θwith a normal direction of a surface of the color improvement film on a cross section perpendicular to the first direction. The first filling layer has a second refractive index n2, and the second refractive index n2 is greater than the first refractive index n1. The first strip-shaped micro-prism layer is gap-filled and planarized with the first filling layer. The electroluminescent display can therefore have a good anti-reflection effect and can improve the hue deviation caused by the reflected light.

Description

Electroluminescent display

The present invention relates to an electroluminescent display, in particular to an electroluminescent display that has a good anti-reflection effect and can improve the problem of the inability to form a purely dark picture due to the deviation of the reflected light hue.

Electroluminescent displays include small-pitch LED displays, mini LED displays, micro LED displays or organic light-emitting diodes Displays (OLED displays) have the advantages of self-luminescence, wide viewing angle, fast response time, high brightness, high contrast, high lumen efficiency, low operating voltage, thin thickness, and flexibility. Therefore, they are used in outdoor information signs and cars. In applications in various scenarios such as display devices or handheld mobile devices, it is foreseeable that they will become mainstream display products.

With the increasing requirements for the dark state hue of the display area of handheld mobile devices such as mobile phones, it is expected that a consistent pure black can be achieved. However, because electroluminescent displays use high-reflectivity reflective electrodes, it is necessary to use the circular polarizer to be installed on the The light-emitting surface of the electroluminescent display is used to solve the problems of the reflection of the reflective electrode on the external ambient light in various bands, which causes the display contrast to decrease and interfere with the image recognition. Therefore, the retardation plate in the circular polarizer must have compensation characteristics for each band. In order to avoid the deviation of reflective hue.

In the conventional non-reflective liquid crystal display, an anti-glare layer or an anti-reflection layer is often provided on the surface to avoid the influence of external ambient light or reduce the reflection of the display surface, and to maintain a consistent reflective hue, and the light guide structure layer is placed on the surface. The surface method of the liquid crystal display solves the grayscale inversion or color shift of the bright state picture, but does not affect the dark state reflective hue.

However, in electroluminescent displays such as organic light-emitting diode displays, in order to better display bright images, the micro-cavity effect between the reflective electrodes is often used to obtain better optical coherence and color purity. After the ambient light of different wavelengths enters the organic light emitting diode display, because the wavelength composition of the ambient light is inconsistent with the luminous intensity combination ratio of the light-emitting sub-pixels of different colors, the hue of the reflected light will be deviated, making the dark black screen not pure black. However, it is difficult to make the bright white picture and the dark black picture have both good chromatic aberration performance. However, the above method of arranging the light guide structure layer on the surface of the liquid crystal display is not suitable for improving the dark-state reflective hue of the electroluminescent display. If the surface of the circular polarizer on the light emitting side of the electroluminescent display has a light guide structure layer, it is easy to split light. More stray light, and the ambient light entering the light guide structure layer is also easy to interfere with the reflected light, multiple repeated refractions cause dispersion and flicker, reduce the anti-reflection effect of the circular polarizer and make the electroluminescent display resolution The display effect is not good, especially for improving the resolution of electroluminescent displays. Compared with liquid crystal displays, the manufacturing process is more difficult. Therefore, it is not advisable to set a light guide structure layer on the surface of the circular polarizing plate of electroluminescent displays at the expense of The resolution is expected to improve the color cast problem.

Therefore, the present invention discloses an electroluminescent display, which has a good anti-reflection effect and can avoid the problem of inability to form a purely dark picture due to the color shift of the reflected light, thereby improving the image quality.

In an embodiment of the present invention, the electroluminescent display includes an electroluminescent display panel; a color improving film attached to the light-emitting surface of the electroluminescent display panel, and the color improving film includes a substrate, a The first strip-shaped micro ridge layer has a first refractive index n1, and includes a plurality of first strip-shaped micro ridges extending along a first direction formed on the substrate, each of the first strip-shaped micro ridges The mirror has at least one first light-guiding bevel, each of the first light-guiding bevels forming an angle θ with the normal direction of the color improving film surface on a cross-section perpendicular to the first direction, and a first leveling layer having A second refractive index n2, and the second refractive index n2 is greater than the first refractive index n1, the first leveling layer covers and planarizes the first strip-shaped micro ridge layer, and is disposed adjacent to the electro-excited light The display panel side; and a circular polarizing plate attached to the surface of the substrate of the color improvement film.

In an embodiment of the present invention, the difference between n1 and n2 is not less than 0.1 and not more than 0.3.

In another embodiment of the present invention, the electroluminescent display panel includes a small-pitch light-emitting diode display panel, a sub-millimeter light-emitting diode display panel, a micron light-emitting diode display panel, or an organic light-emitting diode display panel.

In another embodiment of the present invention, the included angle θ between the first light guide inclined surface of the first strip-shaped micro ridges and the normal direction of the color improving film surface is greater than 0° and less than 20°.

In another embodiment of the present invention, the projection width of the first light guide slopes of the first strip-shaped micro ridges on the color improvement film surface is between 0.1 μm and 1.8 μm.

In another embodiment of the present invention, the height of the first strip-shaped microfins is between 0.9 μm and 5 μm.

In another embodiment of the present invention, when the first light guide slopes of the first strip-shaped micro ridges are adjacent to each other, they are directly connected or separated by a distance.

In another embodiment of the present invention, when the adjacent first light guide slopes are separated by a distance, the distance is the shortest distance between the first light guide slopes, and the distance is between 0.4 μm and Between 12.3μm.

In another embodiment of the present invention, the adjacent first light guide slopes are symmetrical or asymmetrical.

In another embodiment of the present invention, the distances between the first light guide slopes are the same or different from each other.

In another embodiment of the present invention, the electroluminescent display further includes a functional coating formed on the surface of the circular polarizing plate, wherein the functional coating can be selected from hard coating, anti-reflection layer, and anti-glare One of or a combination of groups formed by layers.

In another embodiment of the present invention, the surface of the first leveling layer of the color improvement film of the electroluminescent display further includes a plurality of second strip-shaped microspheres arranged along a second direction formed on the first On a leveling layer, the second strip-shaped micro ridges have at least one second light guide slope in a cross section perpendicular to the second direction; and a second leveling layer covers and planarizes the second strip-shaped micro The second leveling layer is adjacent to the side of the electroluminescent display panel with respect to the second strip-shaped micro-rings. Wherein, the second leveling layer has a third refractive index n3, and n1<n2<n3.

In another embodiment of the present invention, the difference between n2 and n3 is not less than 0.1 and not more than 0.3.

In another embodiment of the present invention, the first direction and the second direction intersect at an angle between 0° and 90°.

The above content of the invention aims to provide a simplified summary of the content of the disclosure, so that readers have a basic understanding of the content of the disclosure. This summary is not a complete summary of the present disclosure, and its intention is not to point out important/key elements of the embodiments of the present invention or to define the scope of the present invention. After referring to the following embodiments, those with ordinary knowledge in the technical field to which the present invention belongs can easily understand the basic spirit of the present invention, as well as the technical means and implementation modes adopted by the present invention.

In order to make the description of the disclosure of the present invention more detailed and complete, the following provides an illustrative description for the implementation aspects and specific embodiments of the present invention; this is not the only way to implement or use the specific embodiments of the present invention. The embodiments disclosed below can be combined or substituted with each other under beneficial circumstances, and other embodiments can also be added to an embodiment without further description or description.

In the following description, many specific details will be described in detail so that the reader can fully understand the following embodiments. However, the embodiments of the present invention may be practiced without these specific details. In other cases, in order to simplify the drawings, well-known structures and devices are only schematically shown in the drawings.

First, please refer to FIGS. 1 and 2 together. FIG. 1 shows a cross-sectional view of an electroluminescent display 1 according to an embodiment of the present invention, and FIG. 2 shows an embodiment according to the present invention. A three-dimensional perspective view of the surface structure of the color improving film 3 of the electroluminescent display 1 disclosed in the aspect. The electroluminescent display 1 includes an electroluminescent display panel 2; a color improving film 3 attached to the light-emitting surface of the electroluminescent display panel 2, and the color improving film 3 includes a substrate 31, a first strip shape The microsphere layer 32 has a first refractive index n1, and includes a plurality of first strip-shaped microspheres 321 extending along a first direction formed on the substrate 31, and each of the first strip-shaped microspheres 321 is formed on the substrate 31. 321 has at least one first light guide inclined surface 321a, and each of the first light guide inclined surfaces 321a forms an included angle θ with the normal direction of the film surface of the color improvement film 3 on a cross section perpendicular to the first direction D1 (Y-axis direction), And a first leveling layer 33 having a second refractive index n2, and the second refractive index n2 is greater than the first refractive index n1, the first leveling layer 33 covers and planarizes the first strip-shaped micro-edge The mirror layer 32 is disposed on the side adjacent to the electroluminescent display panel 2; and a circular polarizing plate 4 is attached to the surface of the substrate 31 of the color improvement film 3.

In an embodiment of the present invention, the electroluminescent display panel 2 is, for example, but not limited to, the small-pitch light-emitting diode display panel, sub-millimeter light-emitting diode display panel, micron light-emitting diode display panel, or organic light-emitting diode display panel in the prior art. For light-emitting diode display panels, for self-luminous display panels with highly reflective electrodes and resonant cavity types, or even self-luminous display panels with integrated touch modules, conventional adhesion methods can be used, without the need to change electrical excitation The laminated structure of the light display panel or the change of its packaging process to increase the internal quantum efficiency, additionally attach the color improvement film of the present invention with a micron-level light-guiding strip-shaped micro-rib structure to the surface of the existing electroluminescent display panel, namely It can achieve the effect of not easily generating stray reflected light, maintaining a low degree of reflection and low color shift.

The circular polarizing plate 4 may be, for example, a laminate of a linear polarizing plate and a retardation plate. The suitable linear polarizing plate can be a linear polarizing plate known in the related art without any particular limitation. The linear polarizing plate may include a polymer film having dichroic dyes aligned thereon. The types of polymer films forming linear polarizers are not particularly limited, as long as they can be dyed with dichroic materials such as iodine or can be used as carriers for dichroic materials, and may include, for example, hydrophilic polymer films (such as Polyvinyl alcohol film, ethylene-vinyl acetate copolymer film, ethylene-vinyl alcohol copolymer film, cellulose film and/or partially saponified film) or polyene alignment film (such as dehydrated polyvinyl alcohol film, dechlorinated polyvinyl alcohol) Vinyl alcohol film) or the like. Considering the dyeing affinity for dichroic materials, the polymer film used in a preferred embodiment of the present invention is a polyvinyl alcohol film. The linear polarizing plate can be produced by any method known in the art, for example, can be produced by a coating process, dry stretching or wet stretching, and the sequence or number of the processes is not particularly limited. The retardation plate can be made, for example, by coating a polymerizable liquid crystal material on a transparent polymer film, aligning it in a plane alignment, and then orienting it after heat or light treatment, and can select a single four depending on the retardation value. The half-wave plate, or the laminated quarter-wave plate and half-wave plate composite film, so that the linearly polarized light passing through the linearly polarized plate can be converted into circularly polarized light.

In an embodiment of the present invention, the material of the substrate 31 of the color improvement film 3 may be polyethylene terephthalate (PET), polycarbonate (PC), cellulose triacetate (TAC), polymethyl Methyl acrylate (PMMA) or cyclic olefin polymer (COP), and its thickness can range from 30 μm to 300 μm.

In an embodiment of the present invention, the first stripe-shaped micro-fin layer 32 can be formed on the substrate 31 by first embossing a first curable resin (not shown) with a first refractive index n1, and then Obtained by curing again. Then, a second curable resin (not shown) having a second refractive index n2 is filled on the surface of the first strip-shaped microfin layer 32 and planarized to form the first leveling layer 33. The curable resin and the second curable resin may be a photo-curable resin or a heat-curable resin, the first refractive index n1 and the second refractive index n2 can be selectively between 1.4 and 1.7, and the first refractive index n1 and the first refractive index n1 and the second refractive index n2 can be selectively between 1.4 and 1.7. The difference of the second refractive index n2 is not less than 0.1 and not more than 0.3. The first curable resin and the second curable resin (not shown) can be, for example, acrylic resin, silicone resin, polyurethane resin, epoxy resin, or a combination thereof.

Please also refer to FIG. 3, which shows a cross-sectional view of the color improvement film 3 according to an embodiment of the present invention. In another embodiment of the present invention, the angle θ between the first light guide inclined surface 321a of the first strip-shaped micro ridges 321 and the film surface normal of the color improvement film 3 is greater than 0° and less than 20°, and each The projection width w of a first light guide inclined surface 321a on the film surface of the color improvement film 3 is between 0.1 μm and 1.8 μm. Under the condition that the first refractive index n1 of the first strip-shaped microscopic layer 32 is smaller than the second refractive index n2 of the first filling layer 33, the external light can be allowed to enter the circular polarizing plate 4 and then pass through the low refractive index The first strip-shaped micro-ridge layer 32 passes through the relatively high refractive index first filling layer 33, so it is not easy to generate additional stray light total reflection interference and reduce the resolution, and the first strip-shaped micro-ridges When the first light guide inclined surface 321a of the mirror 321 is in the range of the included angle θ , for the higher intensity of perpendicularly incident external light after being refracted by the first light guide inclined surfaces 321a to degrade and disperse and homogenize, the circular polarizing plate can still be used 4 At the same time, most of the reflected light generated by the first stripe-shaped microscopic layer 32 in the color improvement film 3 is filtered out to maintain a dark black image. In addition, after the direct light emitted by the electroluminescent display panel 2 with high coherence and no color shift passes through the first light guide inclined surface 321a of the color improvement film 3, it will not be directly refracted, and will cause a reduction in the first place. Less total reflection, and then refracted by the interface between the first stripe-shaped micro ridge layer 32 and the first leveling layer 33, so that direct light can be transmitted to a larger viewing angle, and it is not easy to lose too much brightness, and can be The projection width w and angle θ of the first light guide inclined surface 321a on the film surface of the color improvement film 3 control the ratio of light refraction and total reflection to match different types of electroluminescent display panels to make the electroluminescent display panel 2 emit The light coherence will not be reduced to obtain good optical effects and maintain good contrast.

In another embodiment of the present invention, the height h of each of the first strip-shaped micro ridges 321 is between 0.9 μm and 5 μm, and the first guides of the first strip-shaped micro ridges 321 When the light inclined surfaces 321a are adjacent, they are directly connected or separated by a distance g. When the adjacent first light guiding inclined surfaces 321a are separated by a distance g, the distance g is the shortest between the first light guiding inclined surfaces 321a. The distance is not limited to the distance between the top or bottom of the individual first strip-shaped micro ridges 321, and the distance g is preferably between 0.4 μm and 12.3 μm, so as to provide a certain amount on the first light guide inclined surface 321a Under the function of light splitting and light guiding, it can still have a uniform visual effect. In addition, the height h of the first strip-shaped micro ridges 321, the distance g between two adjacent first light guide slopes 321a, and the included angle θ between the first light guide slopes 321a and the normal line of the film surface can be displayed by different electric excitation lights. The pixel arrangement, pixel size, overall requirements or product design requirements of the panel are independently set to all or part of the same repeating unit. Therefore, the adjacent first light guide slopes 321a can be symmetrical or asymmetrical. The distance g between the first light guide slopes 321a may be the same or different from each other.

4, in another embodiment of the present invention, the electroluminescent display 11 further includes a functional coating 6 formed on the surface of the circular polarizer 4, wherein the functional coating 6 can be selected as a hard coating One or a combination of a group consisting of a layer, an anti-reflection layer, and an anti-glare layer.

Please refer to FIGS. 5 and 6 together. FIG. 5 shows a three-dimensional perspective view of an electroluminescent display 12 according to another embodiment of the present invention, and FIG. 6 shows another perspective view according to the present invention. A three-dimensional perspective view of the surface structure of the color improving film 5 of the electroluminescent display 12 disclosed in an embodiment. The electroluminescent display 12 includes an electroluminescent display panel 2; a color improving film 5 attached to the light-emitting surface of the electroluminescent display panel 2. The color improving film 5 includes a substrate 51 and a first strip The micro-ribbed layer 52 includes a plurality of first strip-shaped micro-ribbed 521 extending along a first direction D1 (Y-axis direction) formed on the substrate 51, and a first leveling layer 53, covering and flat The first strip-shaped micro-element layer 52 is formed, and is disposed on the side adjacent to the electroluminescent display panel 2; and a circular polarizing plate 4 is attached to the surface of the substrate 51 of the color improvement film 3. In addition, the surface of the first leveling layer 53 of the color improvement 5 of the electroluminescent display 12 further includes a plurality of second strip-shaped micro ridges 531 arranged along a second direction D2 (X-axis direction). On a leveling layer 53, the second strip-shaped micro ridges 531 have at least one second light guide slope 531a in a cross section perpendicular to the second direction D2; and a second leveling layer 54 covers and planarizes the The second strip-shaped micro ridges 531, the second filling layer 54 is adjacent to the electroluminescent display panel 2 relative to the second strip-shaped micro ridges 531. Wherein, the first strip-shaped micro ridge layer 52 near the substrate 51 has a first refractive index n1, the first leveling layer 53 has a second refractive index n2, and the second leveling layer 54 has a third The refractive index is n3, and n1<n2<n3. Since the refractive index of these multilayer structures changes according to the direction of the incident light, it is not easy to reflect light from entering the external light, and can further improve the light expansion angle and color uniformity of the display light emitted by the electroluminescent display panel 2.

In another embodiment of the present invention, the second leveling layer 54 may be a third curable resin (not shown) having a third refractive index n3 to fill the surface of the second strip-shaped micro-shaped ridges 531 and make The second leveling layer 54 is formed by planarization, the third refractive index n3 can be selectively between 1.4 and 1.7, and the difference between n2 and n3 is not less than 0.1 and not more than 0.3. The third curable resin may be a photo-curable resin or a heat-curable resin, and may be, for example, acrylic resin, silicone resin, polyurethane resin, epoxy resin, or a combination thereof.

In another embodiment of the present invention, the first direction D1 and the second direction D2 intersect at an angle between 0° and 90°. Further depending on the application requirements of different electroluminescent displays 12, the relative angles of the first light guide slopes 521a of the first strip-shaped micro-beams 521 and the second light guide slopes 531a of the second strip-shaped micro-beams 531 are adjusted. , So that the light expansion direction can be adjusted, and because of the double light guide slope total reflection surface, the light expansion angle can be larger. For the light beams that pass through the first strip-shaped micro ridges 521 or the second strip-shaped micro ridges 531, or the interference pattern generated by the pixel array of the electro-excited light display panel 2, the angle can also be used Adjust and avoid affecting the display quality. Optionally, the first direction D1 in which the first strip-shaped micro-ribs 521 extend or the second direction D2 in which the second strip-shaped micro-ribos 531 extend can be aligned with the absorption axis (not shown) of the circular polarizer 4 (Shown) parallel, but not limited to this.

Please also refer to FIG. 7, which shows a cross-sectional view of a light color improvement structural film 5 according to another embodiment of the present invention. In another embodiment of the present invention, the angle θ 2 between the second light guide inclined surface 531a of the second strip-shaped micro ridges 531 and the film surface normal of the color improving film 5 is greater than 0° and less than 20°, and The projection width w2 of each second light guide inclined surface 531a on the film surface of the color improvement film 5 is between 0.1 μm and 1.8 μm, and the height h2 of each of the second strip-shaped micro ridges 531 is between 0.9 Between μm and 5 μm, the second light guide slopes 531a of the second strip-shaped micro ridges 531 are directly connected or separated by a gap g2 when they are adjacent. When the adjacent second light guide slopes 531a are adjacent When separated by a gap g2, the gap g2 is the shortest distance between the second light guide slopes 531a, and is not limited to the top or bottom distance of the individual second strip-shaped micro ridges 531, and the gap g2 It is preferably between 0.4 μm and 12.3 μm, so that the second light guide slope 531a provides a certain light splitting and light guiding effect, and it can still have a uniform visual effect. In addition, the height h2 of the second strip-shaped micro ridges 531, the distance g2 between the two adjacent second light guide slopes 531a, and the angle θ 2 between the second light guide slopes 531a and the normal line of the film surface, can be seen by different electric excitation lights. The pixel arrangement, pixel size, overall requirements or product design requirements of the display panel are independently set to all or part of the same repeating units. Therefore, the adjacent second light guide slopes 531a may also be symmetrical or non-symmetrical. Symmetrically, the distance g2 between the second light guide inclined surfaces 531a may be the same or different from each other.

In another embodiment of the present invention, the structural dimensions such as the height and spacing of the first strip-shaped micro-ribs 521 and the second strip-shaped micro-ribs 531 may be the same or different.

The following examples are used to further illustrate the present invention, but the present invention is not limited thereto.

Example

Example 1

In the electroluminescent display disclosed in this embodiment 1, the electroluminescent display panel used is an organic light-emitting diode display panel (model: Samsung Tab S2, purchased from Taiwan), which is sequentially mounted on the electroluminescent display panel The color improvement film and the circular polarizer are superimposed on the adhesive layer. The first strip-shaped micro-shaped layer of the color improving film has a plurality of first strip-shaped micro-shaped beams arranged along the first direction. The height of the first strip-shaped micro-shaped beams is 5.0 μm, and the distance between adjacent first strip-shaped micro-shaped beams is 1.2 μm. To 4.8μm, the angle between each first light guide slope of the first strip-shaped micro ridges and the normal line of the color improvement film is an asymmetrical design of 12.5° and 15° staggered arrangement, the first The projection width of the light guide slope on the color improvement film surface is 1.1 μm to 1.3 μm, the first refractive index n1 of the first strip-shaped micro ridge layer is 1.51, and the second refraction of the first leveling layer The rate n2 is 1.61.

Example 2

In the electroluminescent display disclosed in the second embodiment, the electroluminescent display panel used is an organic light-emitting diode display panel (model: Samsung Tab S2, purchased from Taiwan), which is sequentially mounted on the electroluminescent display panel The color improvement film and the circular polarizer are superimposed on the adhesive layer. The first strip-shaped micro-shaped layer of the color improvement film has a plurality of first strip-shaped micro-shaped beams arranged along the first direction. The height of the first strip-shaped micro-shaped beams is 5.0 μm, and the distance between adjacent first strip-shaped micro-shaped beams is 1.4 μm. To 5.7μm, the angle between each first light guide inclined surface of the first strip-shaped micro ridges and the normal line of the color improvement film is 6.5° and 11.5° staggered asymmetrical design, the first The projection width of the light guide slope on the color improvement film surface is 0.6μm to 1.0μm, the first refractive index n1 of the first strip-shaped micronip layer is 1.51, and the second refraction of the first leveling layer The rate n2 is 1.61.

Comparative example

Comparative example 1

Comparative Example 1 uses the same electroluminescent display panel and color improvement film disclosed in Example 1, but its configuration is to sequentially superimpose the circular polarizer and the color improvement film on the electroluminescent display panel in an external paste manner, so that The color improvement film is directly located on the outermost side of the display side.

Comparative example 2

Comparative Example 2 uses the same electroluminescent display panel and color improvement film disclosed in Example 2, but its configuration is to sequentially superimpose the circular polarizing plate and the color improvement film on the electroluminescent display panel in an external paste manner, so that The color improvement film is directly located on the outermost side of the display side.

Please refer to Table 1 for reference. Table 1 shows the Konica Minolta CM-700d used to measure the above-mentioned embodiment and comparative example on a dark black screen. For the reflected light irradiated by the D65 light source close to natural light, SCE (Specular Component Excluded) is used. ) Mode is the reflectivity measured separately for the reflected light of different wavelengths, and in the CIE 1976 (L*a*b*) color space coordinates, the light intensity and color conversion coordinates of the reflected light are compared with the pure black reference point The hue difference value △E is used to evaluate whether the pure black performance of the dark state picture has no color difference. Table 1: The reflectance and hue difference of reflected light of different wavelengths

It can be seen from the measurement data in Table 1 that in the configuration of Comparative Example 1 and Comparative Example 2, the reflectance of each wavelength is significantly higher than that of Example 1 and Example 2, and the dark state of Example 1 and Example 2 Compared with the pure black reference point, the hue difference value ΔE is also smaller. Therefore, the structure of the electroluminescent display of Example 1 and Example 2 can greatly reduce the degree of color shift caused by reflected light, and at the same time The anti-reflection effect of the circular polarizer and the effect closer to the pure black phase are maintained. Among them, the color improvement film structure size matched with the organic light-emitting diode display panel tested in Embodiment 2 is better.

Although the present invention has been disclosed in the above embodiments, it is not intended to limit the present invention. Anyone familiar with the art can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, the protection of the present invention The scope shall be subject to the definition of the attached patent application scope.

1, 11, 12: electroluminescent display

2: Electroluminescent display panel

3, 5: Color improvement film

31, 51: substrate

32, 52: The first stripe-shaped micro-coil layer

321, 521: The first strip of micro

321a, 521a: first light guide slope

531a: The second light guide slope

33, 53: the first leveling layer

4: Circular polarizing plate

531: The second strip of micro-snakes

54: second leveling layer

6: Functional coating

D1: First direction

D2: second direction

w, w2: projection width

h, h2: height

θ 、 θ 2: included angle

g, g2: spacing

FIG. 1 shows a cross-sectional view of an electroluminescent display according to an embodiment of the present invention.

FIG. 2 is a three-dimensional perspective view of the surface structure of the color improving film disclosed according to an embodiment of the present invention.

FIG. 3 shows a cross-sectional view of the color improvement film according to an embodiment of the present invention.

FIG. 4 shows a cross-sectional view of an electroluminescent display according to another embodiment of the present invention.

FIG. 5 shows a three-dimensional perspective view of an electroluminescent display according to another embodiment of the present invention.

FIG. 6 is a three-dimensional perspective view of the surface structure of the color improving film disclosed according to another embodiment of the present invention.

FIG. 7 shows a cross-sectional view of a color improving film according to another embodiment of the invention.

1: Electroluminescent display

2: Electroluminescent display panel

3: Color improvement film

31: substrate

32: The first stripe-shaped micro-sharp layer

321: The first strip of micro-fin

321a: The first light guide slope

33: The first leveling layer

4: Circular polarizing plate

Claims (14)

An electroluminescence display, comprising: an electroluminescence display panel; a color improvement film attached to the light-emitting surface of the electroluminescence display panel, the color improvement film comprising: a substrate; The layer has a first refractive index n1, and includes a plurality of first strip-shaped micro-ribs extending along a first direction formed on the substrate, and each of the first strip-shaped micro-ribos has at least one first Light guide slopes, each of the first light guide slopes forms an angle θ with the normal direction of the color improving film surface on the cross section perpendicular to the first direction; and a first leveling layer having a second refractive index n2 , And the second refractive index n2 is greater than the first refractive index n1, the first leveling layer covers and planarizes the first strip-shaped microscopic layer, and is disposed on the side adjacent to the electroluminescent display panel; and a circle The polarizing plate is attached to the surface of the substrate of the color improvement film. The electroluminescent display according to claim 1, wherein the difference between n1 and n2 is not less than 0.1 and not more than 0.3. The electroluminescent display according to claim 1, wherein the electroluminescent display panel includes a small-pitch light-emitting diode display panel, a sub-millimeter light-emitting diode display panel, a micron light-emitting diode display panel, or an organic light-emitting diode Display panel. The electroluminescent display according to claim 1, wherein the angle θ between the first light guide inclined surface of the first strip-shaped micro ridges and the normal direction of the color improving film surface is greater than 0° and less than 20°. The electroluminescent display according to claim 1, wherein the projection width of the first light guide inclined surface of each of the first strip-shaped microspheres on the color improvement film surface is between 0.1 μm and 1.8 μm . The electroluminescent display according to claim 1, wherein the height of each of the first strip-shaped micro ridges is between 0.9 μm and 5 μm. The electroluminescent display according to claim 1, wherein when the first light guide slopes of the first strip-shaped micro ridges are adjacent to each other, they are directly connected or separated by a distance. The electroluminescent display according to claim 7, wherein when the adjacent first light guide slopes are separated by a distance, the distance is the shortest distance between the first light guide slopes, and the distance is between Between 0.4μm and 12.3μm. The electroluminescent display according to claim 7, wherein the adjacent first light guide slopes are symmetrical or asymmetrical. The electroluminescent display according to claim 7, wherein the distances between the first light guide slopes are the same or different from each other. The electroluminescent display according to claim 1, further comprising a functional coating formed on the surface of the circular polarizing plate, wherein the functional coating can be selected from a hard coating, an anti-reflection layer, and an anti-glare layer One or a combination of groups. The electroluminescent display according to claim 1, wherein the surface of the first leveling layer of the color improvement film further includes a plurality of second strip-shaped micro ridges arranged in a second direction formed on the first filling layer On the flat layer, each of the second strip-shaped micro ridges has at least one second light guide inclined surface, and each of the second light guide inclined surfaces is aligned with the normal line of the color improving film surface on the cross section perpendicular to the second direction The direction forms an included angle θ 2 , and the color improvement film further includes a second leveling layer covering and flattening the second strip-shaped micro ridges. The second leveling layer is relative to the second strip-shaped micro ridges. Adjacent to the electroluminescent display panel side; wherein, the second filling layer has a third refractive index n3, and n1<n2<n3. The electroluminescent display according to claim 12, wherein the difference between n2 and n3 is not less than 0.1 and not more than 0.3. The electroluminescent display according to claim 12, wherein the first direction and the second direction intersect at an angle between 0° and 90°.

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