CROSS-REFERENCE TO RELATED APPLICATION

This application is a Section 371 National Phase application of International Application No. PCT/CN2019/074171, filed on 31 Jan. 2019. which has not yet published, and claims priority to Chinese Patent Application No. 201810125358.5 filed on Feb. 7, 2018, the contents of which are incorporated herein in their entireties by reference.

TECHNICAL FIELD

This disclosure relates to the field of display. Particularly, this disclosure relates to a color filter sheet, a production method of a color filter sheet, and a display apparatus.

BACKGROUND ART

With the continuous development of the display technology, the requirements for the image quality of display apparatuses are higher and higher. With respect to a typical display apparatus, full-color display is achieved by a color filter. For example, a liquid crystal display apparatus may comprise a backlight module, an array substrate, a color filter substrate (color filter sheet), and a liquid crystal layer located between the array substrate and the color filter substrate. White light emitted from the backlight module passes through a color filter layer on the color filter substrate to display various colors.

SUMMARY OF THE INVENTION

In one aspect of this disclosure, there is provided a color filter sheet, comprising:

a base substrate;

a first quantum dot light-emitting portion located on the base substrate, wherein the first quantum dot light-emitting portion has a light incident surface facing the base substrate and a light emergent surface departing from the base substrate, the first quantum dot light-emitting portion is configured to emit light having a second wavelength after excitation with light having a first wavelength from the light incident surface,

wherein one of the light incident surface and the light emergent surface of the first quantum dot light-emitting portion is a convex surface.

In some Examples, the color filter sheet further comprises:

a second quantum dot light-emitting portion located on the base substrate, wherein the second quantum dot light-emitting portion has a light incident surface facing the base substrate and a light emergent surface departing from the base substrate, the second quantum dot light-emitting portion is configured to emit light having a third wavelength after excitation with light having a first wavelength from the light incident surface, wherein the third wavelength is different from the second wavelength.

In some Examples, the light incident surface of the first quantum dot light-emitting portion is a convex surface, and the light incident surface of the second quantum dot light-emitting portion is a convex surface.

In some Examples, the light emergent surface of the first quantum dot light-emitting portion is a convex surface, and the light emergent surface of the second quantum dot light-emitting portion is a convex surface.

In some Examples, the color filter sheet further comprises: a transparent portion for transmitting light having a first wavelength located on the base substrate.

In some Examples, the light having the first wavelength is blue light, and one of the light having the second wavelength and the light having the third wavelength is red light and the other one is green light.

In some Examples, a pixel defining layer is present on the base substrate, the first quantum dot light-emitting portion is located in a first opening of the pixel defining layer, and the convex surface of the first quantum dot light-emitting portion has a radius of curvature in a range of 1 to 5 times the length of the first opening.

In some Examples, the second quantum dot light-emitting portion is located in a second opening of the pixel defining layer, and the convex surface of the second quantum dot light-emitting portion has a radius of curvature in a range of 1 to 5 times the length of the second opening.

In some Examples, the color filter sheet further comprises a Bragg reflection layer, wherein the Bragg reflection layer is located between the base substrate and the first quantum dot light-emitting portion, and is configured to at least transmit a part of light having a first wavelength emitted from a light source; and/or configured to at least partially reflect light having a second wavelength emitted from the first quantum dot light-emitting portion toward the Bragg reflection layer.

In some Examples, the color filter sheet further comprises a Bragg reflection layer, wherein the Bragg reflection layer is located between the base substrate and the second quantum dot light-emitting portion, and is configured to at least transmit a part of light having a first wavelength emitted from a light source; and/or configured to at least partially reflect light having a third wavelength emitted from the second quantum dot light-emitting portion toward the Bragg reflection layer.

In another aspect of this disclosure, there is provided a display apparatus, comprising a light source and the color filter sheet of any one of the Examples described above. The light source has a light emergent side facing the base substrate of the color filter sheet, and the light source is configured to emit light having the first wavelength.

In still another aspect of this disclosure, there is provided a production method of a color filter sheet, comprising:

providing a first quantum dot ink comprising a first quantum dot and a first resin, wherein the first quantum dot is configured to emit light having a second wavelength after excitation with light having a first wavelength;

providing a base substrate and forming a pixel defining layer on the base substrate;

inkjet-printing the first quantum dot ink onto a first opening of the pixel defining layer to form a first quantum dot ink layer having a printed surface; and

drying the first quantum dot ink layer with the printed surface facing down to form a first quantum dot light-emitting portion in which the printed surface is a convex surface.

In some Examples, the method further comprises:

providing a second quantum dot ink comprising a second quantum dot and a second resin, wherein the second quantum dot is configured to emit light having a third wavelength after excitation with light having a first wavelength, wherein the third wavelength is different from the second wavelength; and

inkjet-printing the second quantum dot ink onto a second opening of the pixel defining layer to form a second quantum dot ink layer having a printed surface; and

drying the second quantum dot ink layer with the printed surface of the second quantum dot ink facing down to form a second quantum dot light-emitting portion in which the printed surface is a convex surface.

In some Examples, the method further comprises:

forming a transparent portion for transmitting light having a first wavelength in a third opening of the pixel defining layer.

In some Examples, a step of spin drying is used in the drying, and the spin drying has a spin speed of 10 rpm to 1000 rpm, a drying temperature of 20° C. to 160° C., and a drying time of 1 minute to 60 minutes.

In some Examples, the convex surface of the first quantum dot light-emitting portion has a radius of curvature in a range of 1 to 5 times the length of the first opening.

In some Examples, the convex surface of the second quantum dot light-emitting portion has a radius of curvature in a range of 1 to 5 times the length of the second opening.

In some Examples, the first quantum dot ink has a viscosity of 5-20 cPs and a surface tension of 20-40 dynes.

In some Examples, the second light-emitting quantum dot ink has a viscosity of 5-20 cPs and a surface tension of 20-40 dynes.

