US-20260130035-A1 - DISPLAY DEVICE HAVING HIGH COLOR PURITY AND COLOR CONVERSION STRUCTURE THEREOF

US20260130035A1US 20260130035 A1US20260130035 A1US 20260130035A1US-20260130035-A1

Abstract

A display device having a high color purity and a color conversion structure of the display device having the high color purity. The color conversion structure is configured to convert light emitted from a blue light substrate, and includes a color conversion layer, a first filter layer disposed on the color conversion layer, and a second filter layer disposed on the first filter layer. The color conversion layer includes a blue light-transmitting region, a green conversion region, and a red conversion region. The first filter layer includes another blue light-transmitting region that corresponds in position to the blue light-transmitting region. The first and second filter layers can filter blue light of different ratios, so that color purities of red light and green light are enhanced and brightness of the blue light is ensured.

Inventors

ZONG-LIANG CHEN
Yu-Chang Hu
GUAN-YU LI
Hsin-I Lu
Shyi-Ming Pan
Feng-Hui Chuang

Assignees

HARVATEK CORPORATION

Dates

Publication Date: 20260507
Application Date: 20250908
Priority Date: 20241107

Claims (11)

1 . A display device having a high color purity, comprising: a blue light substrate, wherein the blue light substrate includes a first blue light-emitting element, a second blue light-emitting element, and a third blue light-emitting element that are spaced apart from each other; and a color conversion structure including: a color conversion layer disposed on the blue light substrate, wherein the color conversion layer includes a blue light-transmitting region that corresponds in position to the first blue light-emitting element, a green conversion region that corresponds in position to the second blue light-emitting element, and a red conversion region that corresponds in position to the third blue light-emitting element; a first filter layer disposed on the color conversion layer, wherein the first filter layer includes another blue light-transmitting region that corresponds in position to the blue light-transmitting region, and an optical density for each 1 micrometer thickness of the first filter layer within a wavelength range of from 380 nm to 500 nm is from 0.4 to 0.8; and a second filter layer disposed on the first filter layer, wherein an optical density for each 1 micrometer thickness of the second filter layer within the wavelength range of from 380 nm to 500 nm is from 0.8 to 1.2.
2 . The display device according to claim 1 , wherein the color conversion structure includes a patterned metal layer, and the patterned metal layer is disposed on the second filter layer for division of a plurality of sub-pixel units; wherein the first filter layer includes a first blue light-blocking region disposed on at least one side of the another blue light-transmitting region, and the second filter layer includes a second blue light-blocking region; and wherein a blue sub-pixel unit of the plurality of sub-pixel units includes the first blue light-emitting element and the blue light-transmitting region, the another blue light-transmitting region, and the second blue light-blocking region that are sequentially arranged in a direction away from a light-emitting surface of the first blue light-emitting element, a green sub-pixel unit of the plurality of sub-pixel units includes the second blue light-emitting element and the green conversion region, the first blue light-blocking region, and the second blue light-blocking region that are sequentially arranged in a direction away from a light-emitting surface of the second blue light-emitting element, and a red sub-pixel unit of the plurality of sub-pixel units includes the third blue light-emitting element and the red conversion region, the first blue light-blocking region, and the second blue light-blocking region that are sequentially arranged in a direction away from a light-emitting surface of the third blue light-emitting element.
3 . The display device according to claim 2 , wherein the second blue light-blocking region includes a plurality of thick layer regions and a plurality of thin layer regions that are alternately arranged, and a thickness ratio of the plurality of thick layer regions to the plurality of thin layer regions is from 6:1 to 10:1; and wherein the patterned metal layer includes a plurality of metal spacers that respectively correspond in position to the plurality of thin layer regions, and the plurality of thick layer regions are respectively disposed in a plurality of spaces between the plurality of metal spacers.
4 . The display device according to claim 3 , further comprising a transparent cover, wherein the transparent cover covers the color conversion structure, the patterned metal layer is disposed between the second filter layer and the transparent cover, and each of the plurality of metal spacers is interlaid between the transparent cover and a corresponding one of the plurality of thin layer regions.
5 . The display device according to claim 3 , wherein the first filter layer and the second filter layer each contain a yellow pigment, and the yellow pigment is a yellow organic pigment, a yellow inorganic pigment, or a combination thereof.
6 . The display device according to claim 5 , wherein the first filter layer and the second filter layer are each formed by a photosensitive resin composition that contains the yellow pigment, a thickness of the first filter layer is within a range of from 1.6 μm to 2.5 μm, and a thickness of the plurality of thick layer regions in the second filter layer is within a range of from 0.6 μm to 1 μm; wherein, based on a total weight of the photosensitive resin composition forming the first filter layer being 100 wt %, a content of the yellow pigment in the photosensitive resin composition forming the first filter layer is from 40 wt % to 60 wt %; and wherein, based on a total weight of the photosensitive resin composition forming the second filter layer being 100 wt %, a content of the yellow pigment in the photosensitive resin composition forming the second filter layer is from 10 wt % to 30 wt %.
7 . A color conversion structure for converting light emitted from a blue light substrate, the blue light substrate including a first blue light-emitting element, a second blue light-emitting element, and a third blue light-emitting element that are spaced apart from each other, and the color conversion structure comprising: a color conversion layer disposed on the blue light substrate, wherein the color conversion layer includes a blue light-transmitting region that corresponds in position to the first blue light-emitting element, a green conversion region that corresponds in position to the second blue light-emitting element, and a red conversion region that corresponds in position to the third blue light-emitting element; a first filter layer disposed on the color conversion layer, wherein the first filter layer includes another blue light-transmitting region that corresponds in position to the blue light-transmitting region, and an optical density for each 1 micrometer thickness of the first filter layer within a wavelength range of from 380 nm to 500 nm is from 0.4 to 0.8; and a second filter layer disposed on the first filter layer, wherein an optical density for each 1 micrometer thickness of the second filter layer within the wavelength range of from 380 nm to 500 nm is from 0.8 to 1.2.
8 . The color conversion structure according to claim 7 , wherein the color conversion structure includes a patterned metal layer, and the patterned metal layer is disposed on the second filter layer for division of a plurality of sub-pixel units; wherein the first filter layer includes a first blue light-blocking region disposed on at least one side of the another blue light-transmitting region, and the second filter layer includes a second blue light-blocking region; and wherein a blue sub-pixel unit of the plurality of sub-pixel units includes the first blue light-emitting element and the blue light-transmitting region, the another blue light-transmitting region, and the second blue light-blocking region that are sequentially arranged in a direction away from a light-emitting surface of the first blue light-emitting element, a green sub-pixel unit of the plurality of sub-pixel units includes the second blue light-emitting element and the green conversion region, the first blue light-blocking region, and the second blue light-blocking region that are sequentially arranged in a direction away from a light-emitting surface of the second blue light-emitting element, and a red sub-pixel unit of the plurality of sub-pixel units includes the third blue light-emitting element and the red conversion region, the first blue light-blocking region, and the second blue light-blocking region that are sequentially arranged in a direction away from a light-emitting surface of the third blue light-emitting element.
9 . The color conversion structure according to claim 8 , wherein the second blue light-blocking region includes a plurality of thick layer regions and a plurality of thin layer regions that are alternately arranged, and a thickness ratio of the plurality of thick layer regions to the plurality of thin layer regions is from 6:1 to 10:1; and wherein the patterned metal layer includes a plurality of metal spacers that respectively correspond in position to the plurality of thin layer regions, and the plurality of thick layer regions are respectively disposed in a plurality of spaces between the plurality of metal spacers.
10 . The color conversion structure according to claim 9 , wherein the first filter layer and the second filter layer each contain a yellow pigment, and the yellow pigment is a yellow organic pigment, a yellow inorganic pigment, or a combination thereof.
11 . The color conversion structure according to claim 10 , wherein the first filter layer and the second filter layer are each formed by a photosensitive resin composition that contains the yellow pigment, a thickness of the first filter layer is within a range of from 1.6 μm to 2.5 μm, and a thickness of the plurality of thick layer regions in the second filter layer is within a range of from 0.6 μm to 1 μm; wherein, based on a total weight of the photosensitive resin composition forming the first filter layer being 100 wt %, a content of the yellow pigment in the photosensitive resin composition forming the first filter layer is from 40 wt % to 60 wt %; and wherein, based on a total weight of the photosensitive resin composition forming the second filter layer being 100 wt %, a content of the yellow pigment in the photosensitive resin composition forming the second filter layer is from 10 wt % to 30 wt %.

Description

CROSS-REFERENCE TO RELATED PATENT APPLICATION This application claims the benefit of priority to Taiwan Patent Application No. 113142634, filed on Nov. 7, 2024. The entire content of the above identified application is incorporated herein by reference. Some references, which may include patents, patent applications and various publications, may be cited and discussed in the description of this disclosure. The citation and/or discussion of such references is provided merely to clarify the description of the present disclosure and is not an admission that any such reference is “prior art” to the disclosure described herein. All references cited and discussed in this specification are incorporated herein by reference in their entireties and to the same extent as if each reference was individually incorporated by reference. FIELD OF THE DISCLOSURE The present disclosure relates to a field of display devices, and more particularly to a display device having a high color purity and a color conversion structure thereof. BACKGROUND OF THE DISCLOSURE With the development of technology, latest display techniques have achieved significant improvement in terms of display image quality, color performance, energy consumption, etc. In various display technologies, mini light-emitting diodes (mini LEDs), micro LEDs, or organic light-emitting diode (OLEDs) have been considered key technologies in next-generation display. An LED display is a display device that uses an array of light-emitting diodes integrated on a substrate as display pixels. In a common approach, a quantum dot material is applied to a color filter for cooperation with a blue LED backlight module, and a full color display can be achieved by photoluminescence. For example, in the structure of an existing quantum dot color filter (QDCF), a red filter unit includes red quantum dots and can emit red light after being excited by blue light, a green filter unit includes green quantum dots and can emit green light after being excited by the blue light, and a blue filter unit is formed by a transparent polymer material to allow the blue light to pass through. However, blue light from a blue LED cannot be 100% converted into the red light and the green light by the quantum dots. The blue light partially passes through the red filter unit and the green filter unit, so that a color purity of the red light and that of the green light are not high. Furthermore, if a driving current of the blue LED is large, the blue light may easily be too strong in a region where the blue filter unit is located, thereby resulting in a bluish overall display effect. SUMMARY OF THE DISCLOSURE In response to the above-referenced technical inadequacies, the present disclosure provides a display device having a high color purity and a color conversion structure thereof. The color conversion structure of the present disclosure is configured to convert light emitted from a blue light substrate, and can effectively reduce negative influences of background blue light on a display color. In order to solve the above-mentioned problems, one of the technical aspects adopted by the present disclosure is to provide a display device having a high color purity. The display device includes a blue light substrate and a color conversion structure. The blue light substrate includes a first blue light-emitting element, a second blue light-emitting element, and a third blue light-emitting element that are spaced apart from each other. The color conversion structure includes a color conversion layer, a first filter layer, and a second filter layer. The color conversion layer is disposed on the blue light substrate, and includes a blue light-transmitting region that corresponds in position to the first blue light-emitting element, a green conversion region that corresponds in position to the second blue light-emitting element, and a red conversion region that corresponds in position to the third blue light-emitting element. The first filter layer is disposed on the color conversion layer, and includes another blue light-transmitting region that corresponds in position to the blue light-transmitting region. The second filter layer is disposed on the first filter layer. An optical density for each 1 micrometer thickness of the first filter layer within a wavelength range of from 380 nm to 500 nm is from 0.4 to 0.8, and an optical density for each 1 micrometer thickness of the second filter layer within the wavelength range of from 380 nm to 500 nm is from 0.8 to 1.2. In order to solve the above-mentioned problems, another one of the technical aspects adopted by the present disclosure is to provide a color conversion structure for converting light emitted from a blue light substrate. The blue light substrate includes a first blue light-emitting element, a second blue light-emitting element, and a third blue light-emitting element that are spaced apart from each other. The color conversion structure includes a col