CN104360540A - Display device - Google Patents

Abstract

The invention discloses a display device. The display device is used for solving the problems of the existing display devices that the light conversion ratio is low and the display color cast is high. The display device comprises a display panel and a backlight module, wherein the display panel comprises an array substrate, a color film substrate and a liquid crystal layer, wherein the array substrate and the color film substrate are arranged oppositely, and the liquid crystal layer is arranged between the array substrate and the color film substrate; a monochromatic quantum dot film is arranged on one face, opposite to the array substrate, of the color film substrate and comprises a red quantum dot film, a green quantum dot film and a transparent film which correspond to sub-pixels; an upper polarizer layer is arranged between the color film substrate and the liquid crystal layer, and a lower polarizer layer is arranged on one face, which is not adjacent to the liquid crystal layer, of the array substrate. The display panel further comprises orientation layers, wherein the orientation layers are at least arranged between the upper polarizer layer and the liquid crystal layer.

Description

a display device

technical field

The present invention relates to the field of display technology, in particular to a display device.

Background technique

Thin Film Transistor Liquid Crystal Display (TFT-LCD) has the characteristics of small size, low power consumption, and no radiation. It has developed rapidly in recent years and occupies a dominant position in the current flat panel display market. At present, TFT-LCD has been widely used in various large, medium and small-sized products, covering almost the main electronic products in today's information society, such as LCD TV, high-definition digital TV, computer (desktop and notebook), mobile phone, PDA, GPS, car display, projection display, video camera, digital camera, electronic watch, calculator, electronic instrument, meter, public display and virtual display, etc.

The color filter substrate in the display panel of TFT-LCD includes a base substrate, and a color-resist layer and a black matrix located on the base substrate. The color-resist layer includes color resistance of red/green/blue primary colors; When displaying a device, the backlight is generally a white backlight. The white backlight includes mixed light of blue light and yellow light. After being filtered by the color resist layer of the color filter substrate, only the monochromatic light is obtained, and most of the light energy will be lost. Therefore, The conversion rate of the color-resist layer to the backlight is low; at the same time, after the white backlight is filtered by the color-resist layer of the color filter substrate, only each monochromatic light contains unexpected colors, which will lead to a large color shift during display.

Contents of the invention

The object of the present invention is to provide a display device to solve the problems of low light conversion rate and large display color shift in existing display devices.

The purpose of the present invention is achieved through the following technical solutions:

An embodiment of the present invention provides a display device, including a display panel, and a backlight module that provides a blue backlight for the display panel;

The display panel includes an array substrate and a color filter substrate oppositely arranged, and a liquid crystal layer arranged between the array substrate and the color filter substrate;

A monochromatic quantum dot film is provided on the side of the color filter substrate opposite to the array substrate, and the monochromatic quantum dot film includes a red quantum dot film corresponding to the red sub-pixel and a red quantum dot film corresponding to the green sub-pixel arranged in sequence. Green quantum dot film, and a transparent film corresponding to the blue sub-pixel;

An upper polarizing layer is arranged between the color filter substrate and the liquid crystal layer, and a lower polarizing layer is arranged on a side of the array substrate not adjacent to the liquid crystal layer, and the upper polarizing layer is used to make the lower polarizing layer The linearly polarized light passed through the layer continues to reach the monochromatic quantum dot film in the state of linearly polarized light;

The display panel further includes an alignment layer disposed at least between the upper polarizing layer and the liquid crystal layer.

In the embodiment of the present invention, the upper polarizing layer is disposed between the color filter substrate of the display panel and the liquid crystal layer, and the blue backlight first reaches the upper polarizing light after being polarized by the lower polarizing layer. After being analyzed by the upper polarizing layer, it reaches the monochromatic quantum dot film, and the blue backlight reaching the red quantum dot film and the green quantum dot film can be completely converted, thereby improving the light conversion of the color film substrate to the backlight At the same time, based on the complete conversion of the backlight, the transmittance of different pixels of red/green/blue is the same, thereby reducing the problem of large color shift.

Preferably, the absorption axes of the upper polarizing layer and the lower polarizing layer are perpendicular, and the initial display mode of the display panel is a normally black mode; or, the absorption axes of the upper polarizing layer and the lower polarizing layer are parallel , the initial display mode of the display panel is normally white mode. The display panel in the embodiment of the present invention provides normally black and normally white display modes.

Preferably, the upper polarizing layer and the lower polarizing layer are polarizing films coated on the color filter substrate and the array substrate respectively, or are respectively arranged on the color filter substrate and the array substrate polarizer. In the embodiment of the present invention, the lower polarizing layer of the upper polarizing layer may be a film layer fixedly arranged on a corresponding substrate, or may be an adjustable polarizer to improve the compatibility of the display panel.

Preferably, the display panel also includes a black matrix, the black matrix is arranged between the upper polarizing layer and the monochromatic quantum dot film; or, the black matrix is arranged between the monochromatic quantum dot film and the between the color filter substrates. In the embodiment of the present invention, the black matrix can block the area between adjacent single-color quantum dot films to prevent color mixing in the display panel.

Preferably, the alignment layer is also arranged between the array substrate and the liquid crystal layer.

Preferably, the red quantum dot film is composed of red quantum dot particles mixed with photoresist, the green quantum dot film is composed of green quantum dot particles mixed with photoresist, and the red quantum dot particles and the green quantum dots The particle diameter ranges from 2 to 6 microns;

The transparent film is composed of transparent organic matter doped scattering particles, and the diameter range of the scattering particles is 2-10 nanometers.

Preferably, the red quantum dot particles and the green quantum dot particles are CdTe particles or CdSe particles.

Preferably, the wavelength range of the emission spectrum of the backlight module is 400-490 nanometers.

The beneficial effects of the embodiments of the present invention are as follows: the upper polarizing layer is arranged between the color filter substrate of the display panel and the liquid crystal layer, and the blue backlight first reaches the The upper polarizing layer, after being analyzed by the upper polarizing layer, reaches the monochromatic quantum dot film, and the blue backlight reaching the red quantum dot film and the green quantum dot film can be completely converted, thereby improving the color film substrate to the backlight. Light conversion rate; at the same time, based on the complete conversion of the backlight, the transmittance of different pixels of red/green/blue is the same, thereby reducing the problem of large color shift.

Description of drawings

FIG. 1 is a hierarchical schematic diagram of a display device provided by an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a display device including a first display panel provided by an embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a second display panel provided by an embodiment of the present invention.

Detailed ways

The implementation process of the embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings. It should be noted that the same or similar reference numerals represent the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the figures are exemplary only for explaining the present invention and should not be construed as limiting the present invention.

Referring to FIG. 1 and FIG. 2, an embodiment of the present invention provides a display device 200, including a display panel 100 and a backlight module 300 providing a blue backlight. The display panel 100 includes an array substrate 1 and a color filter substrate 2 arranged oppositely, and The liquid crystal layer 3 is disposed between the array substrate 1 and the color filter substrate 2 , and the backlight module 300 is disposed on the side of the display panel 100 where the array substrate 1 is located.

A monochromatic quantum dot film 4 is arranged on the opposite side of the color filter substrate 2 to the array substrate 1, and the monochromatic quantum dot film 4 includes a red quantum dot film 41 corresponding to the red sub-pixel and a green quantum dot film 41 corresponding to the green sub-pixel arranged in sequence. A quantum dot film 42 and a transparent film 43 corresponding to the blue sub-pixel. In the embodiment of the present invention, the monochromatic quantum dot film 4 combined with the red quantum dot film 41, the green quantum dot film 42 and the transparent film 43 is used as a color resistance, the red quantum dot film 41 can pass through red light, and the green quantum dot film 42 can transmit green light, and the transparent film 43 can transmit blue light when the backlight is blue light. It should be noted that the quantum dots (Quantum Dots, QD) in the red quantum dot film 41 and the green quantum dot film 42 can also be called nanocrystals. composed of nanoparticles. The particle size of quantum dots is generally between 1 and 20 nm. Since electrons and holes are quantum-confined, the continuous energy band structure becomes a discrete energy level structure with molecular characteristics, and can emit fluorescence after being excited. The emission spectrum of quantum dots can be controlled by changing the size of quantum dots. By changing the size and chemical composition of quantum dots, the emission spectrum can cover the entire visible light region. Taking cadmium telluride (CdTe) quantum dots as an example, when its particle size grows from 2.5nm to 4.0nm, their emission wavelength can be red-shifted from 510nm to 660nm.

An upper polarizing layer 6 is disposed between the color filter substrate 2 and the liquid crystal layer 3, and a lower polarizing layer 7 is disposed on a side of the array substrate 1 that is not adjacent to the liquid crystal layer 3, and the upper polarizing layer 6 is used to transmit the lower polarizing layer 7. The linearly polarized light continues to reach the monochromatic quantum dot film 4 in the state of linearly polarized light. It should be noted that the upper polarizing layer 6 must be arranged between the color filter substrate 2 and the liquid crystal layer 3, that is, the upper polarizing layer 6 is located in front of the monochromatic quantum dot film 4 in the optical path from the backlight to the output of the display panel. The reason is that : The upper polarizing layer 6 is located behind the monochromatic quantum dot film 4 in the optical path from the backlight to the output of the display panel 100, then during the display process of the display panel 100, the lower polarizing layer 7 polarizes the backlight to obtain linearly polarized light, if the linear polarization When light reaches the monochromatic quantum dot film 4 without passing through the upper polarizing layer 6, it will be scattered by the monochromatic quantum dot film to form elliptically polarized light, which will be blocked after reaching the upper polarizing layer 6, resulting in a display panel 100 Therefore, the upper polarizing layer 6 must be located in front of the monochromatic quantum dot film 4 in the light path from the backlight to the display panel.

The display panel 100 further includes an alignment layer 8 disposed at least between the upper polarizer and the liquid crystal layer 3 . Of course, in order to better align the liquid crystal molecules in the liquid crystal layer 3 , the alignment layer 8 can also be arranged between the array substrate 1 and the liquid crystal layer 3 as shown in FIG. 2 , and details will not be repeated here.

In the embodiment of the present invention, the upper polarizing layer 6 is arranged between the color filter substrate 2 and the liquid crystal layer 3 of the display panel 100, and the blue backlight is polarized by the lower polarizing layer 7 and first reaches the upper polarizing layer 6, and then is polarized by the upper polarizing layer. 6 After the polarization analysis reaches the monochromatic quantum dot film 4, the blue backlight reaching the red quantum dot film and the green quantum dot film can be completely converted, thereby improving the light conversion rate of the color film substrate 2 to the backlight; at the same time, based on the backlight Complete conversion, different pixels of red/green/blue have the same transmittance, thus reducing the problem of large color cast.

Preferably, the absorption axes of the upper polarizer layer 6 and the lower polarizer layer 7 are perpendicular or parallel, and when the absorption axes of the upper polarizer layer 6 and the lower polarizer layer 7 are perpendicular, a normally black display mode is provided; the upper polarizer layer 6 and the lower polarizer layer When the absorption axes of the polarizing layer 7 are parallel, a normally white display mode is provided.

Preferably, the upper polarizing layer 6 and the lower polarizing layer 7 are polarizing films coated on the color filter substrate 2 and the array substrate 1 respectively, that is, the upper polarizing layer 6 and the lower polarizing layer 7 are respectively formed on the color filter substrate 2 and the array substrate. The film layer on the substrate 1 is fixed on the color filter substrate 2 and the array substrate 1. This structure is conducive to reducing the thickness of the display panel; or the upper polarizing layer 6 and the lower polarizing layer 7 are respectively arranged on the color filter substrate 2 and the array substrate 1. The polarizers on the array substrate 1, that is, the upper polarizer layer 6 and the lower polarizer layer 7 are polarizers that can be separated from the color filter substrate 2 and the array substrate 1 respectively, and this structure facilitates separate preparation and assembly.

Preferably, the display panel 100 further includes a black matrix 9 disposed between the upper polarizing layer 6 and the monochromatic quantum dot film 4 , such as the first display panel 100 in the display device 200 shown in FIG. 2 . In the embodiment of the present invention, the black matrix 9 can block the area between adjacent single-color quantum dot films 4 to prevent color mixing in the display panel.

Preferably, the black matrix 9 can also be arranged between the monochromatic quantum dot film 4 and the color filter substrate 2, such as the second display panel 100 shown in FIG. 3 (the reference numerals are the same as those in FIG. 2 ). In the embodiment of the present invention, during the manufacturing process, the black matrix 9 is located at the end position from the backlight to the light output of the display panel, which is beneficial to shielding the wiring and can avoid color mixing between adjacent single-color quantum dot films 4 to the greatest extent.

Preferably, the red quantum dot film 41 is composed of red quantum dot particles mixed with photoresist, the green quantum dot film 42 is composed of green quantum dot particles mixed with photoresist, and the diameter range of red quantum dot particles and green quantum dot particles is 2 ~6 microns; the transparent film 43 is composed of transparent organic matter doped with scattering particles, the diameter of the scattering particles ranges from 2 to 10 nanometers, the heat dissipation particles can be organic or inorganic, and materials with a refractive index no greater than or much smaller than the transparent organic matter are selected .

Preferably, the red quantum dot particles and the green quantum dot particles are CdTe particles or CdSe particles.

Preferably, the wavelength range of the emission spectrum of the backlight module 300 is 400-490 nanometers.

The beneficial effects of the embodiment of the present invention are as follows: in the display device 200, the backlight module 300 provides a blue backlight, so that the light transmittance of each sub-pixel is the same, thereby reducing color shift; on the other hand, the upper polarizing layer 6 Set between the color filter substrate 2 and the liquid crystal layer 3, the backlight is polarized by the lower polarizing layer 7 and first reaches the upper polarizing layer 6, and after being analyzed by the upper polarizing layer 6, reaches the monochromatic quantum dot film 4, the monochromatic quantum dot film 4 Realize the function of color resistance, and at the same time, the linearly polarized light is excited and emits scattered light, which can convert all the blue backlight, thereby improving the light conversion rate.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalent technologies, the present invention also intends to include these modifications and variations.

Claims (8)

1. A display device, characterized in that it comprises a display panel, a backlight module that provides a blue backlight for the display panel; The display panel includes an array substrate and a color filter substrate oppositely arranged, and a liquid crystal layer arranged between the array substrate and the color filter substrate; A monochromatic quantum dot film is provided on the side of the color filter substrate opposite to the array substrate, and the monochromatic quantum dot film includes a red quantum dot film corresponding to the red sub-pixel and a red quantum dot film corresponding to the green sub-pixel arranged in sequence. Green quantum dot film, and a transparent film corresponding to the blue sub-pixel; An upper polarizing layer is arranged between the color filter substrate and the liquid crystal layer, and a lower polarizing layer is arranged on a side of the array substrate not adjacent to the liquid crystal layer, and the upper polarizing layer is used to make the lower polarizing layer The linearly polarized light passed through the layer continues to reach the monochromatic quantum dot film in the state of linearly polarized light; The display panel further includes an alignment layer disposed at least between the upper polarizing layer and the liquid crystal layer. 2. The display device according to claim 1, wherein the absorption axes of the upper polarizing layer and the lower polarizing layer are perpendicular, and the initial display mode of the display panel is a normally black mode; or, the The absorption axes of the upper polarizing layer and the lower polarizing layer are parallel, and the initial display mode of the display panel is normally white mode. 3. The display device according to claim 2, wherein the upper polarizing layer and the lower polarizing layer are polarizing films coated on the color filter substrate and the array substrate respectively, or are respectively set Polarizers on the color filter substrate and the array substrate. 4. The display device according to any one of claims 1 to 3, wherein the display panel further comprises a black matrix, and the black matrix is arranged between the upper polarizing layer and the monochromatic quantum dot film or, the black matrix is arranged between the monochromatic quantum dot film and the color filter substrate. 5. The display device according to any one of claims 1 to 3, wherein the alignment layer is further disposed between the array substrate and the liquid crystal layer. 6. The display device according to claim 1, wherein the red quantum dot film is composed of red quantum dot particles mixed with photoresist, and the green quantum dot film is composed of green quantum dot particles mixed with photoresist , the diameter range of the red quantum dot particles and the green quantum dot particles is 2-6 microns; The transparent film is composed of transparent organic matter doped scattering particles, and the diameter range of the scattering particles is 2-10 nanometers. 7. The display device according to claim 6, wherein the red quantum dot particles and the green quantum dot particles are CdTe particles or CdSe particles. 8 . The display device according to claim 1 , wherein the light emitting spectrum of the backlight module has a wavelength range of 400-490 nanometers.