CN109976037B

CN109976037B - Lateral backlight source and display device thereof

Info

Publication number: CN109976037B
Application number: CN201910270165.3A
Authority: CN
Inventors: 向昌明
Original assignee: TCL Huaxing Photoelectric Technology Co Ltd
Current assignee: TCL Huaxing Photoelectric Technology Co Ltd
Priority date: 2019-04-04
Filing date: 2019-04-04
Publication date: 2021-12-03
Anticipated expiration: 2039-04-04
Also published as: CN109976037A

Abstract

The invention relates to a lateral backlight source and a display device thereof, wherein the lateral backlight source comprises: the device comprises a substrate, a condenser, a diffuse reflection back plate and a double-sided prism diffusion plate. The condenser comprises a support, a light source, a first reflecting piece, a second reflecting piece and a connecting frame. The invention primarily compresses a large-angle lambertian-like light source emitted by an LED into a small angle by using a fiber lens of a condenser; then utilize the breach on the last bottom surface of first reflection piece to pass through the minimum angle light after the primary convergence of fiber lens, utilize first plane of reflection to carry out the primary reflection with the large angle class Lambert light source of fiber lens primary coupling to the second plane of reflection and carry out secondary reflection and finally obtain the emergent light of small angle to avoid using the light guide plate, reduction in production cost has avoided the influence of the thermal warping problem of light guide plate to optical property.

Description

Lateral backlight source and display device thereof

Technical Field

The invention relates to the technical field of display, in particular to a lateral backlight source and a display device thereof.

Background

With the development of liquid crystal display technology, the application field of liquid crystal displays, especially color liquid crystal displays, is also widening. Pulled by the market of liquid crystal displays and the backlight industry, the liquid crystal display displays a splendid scene. Liquid crystal displays are passive light emitting elements and the display screen itself does not emit light but is illuminated by a backlight below it. The backlight source and the liquid crystal display screen are combined together to form the liquid crystal display module.

The so-called BackLight (BackLight) is a light source located behind a Liquid Crystal Display (LCD), and its lighting effect will directly affect the visual effect of the liquid crystal display module (LCM). The backlight source mainly comprises a light source, a light guide plate, an optical film, a plastic frame and the like. The backlight source has the characteristics of high brightness, long service life, uniform light emission and the like. The backlight source is divided into a direct type backlight source and an edge type backlight source according to the distribution position of the light source.

In the direct type backlight, a light source (an LED wafer array) and a printed circuit board are arranged at the bottom of the backlight, and light rays are emitted from the LEDs, pass through a reflector plate at the bottom and then uniformly emitted through a diffusion plate and a brightness enhancement film on the surface.

The edge-lit backlight is a backlight in which linear or point-like light sources are arranged on the side of a specially designed light guide plate. The light guide plate principle is to utilize the interference phenomenon that the distribution of the mesh points at the bottom of the light guide acrylic plate destroys light, and to uniformly convert a linear light source into a surface light source, and the light guide plate has the function of guiding the scattering direction of light, so that the light distribution is more uniform, the shadow of a reflection point cannot be seen from the front, the brightness of the panel is improved, the uniformity of the brightness of the panel is ensured, and the excellent light guide plate has great influence on backlight.

The liquid crystal backlight is a planar uniform lighting device, and cold cathode fluorescent lamps or LED light bars as light sources are arranged on two sides or one side (possibly a long side or a short side) of the whole backlight. The cold cathode lamp tube is a linear light source, the LED is a point light source, and a light guide plate is needed for converting the light source into a surface light source. The light guide plate is generally made of acrylic plastic with high light transmittance, and the surface is very smooth and flat, so that most of the internal light can be regularly and totally reflected on the flat surface of the light guide plate and can not be emitted out of the light guide plate. The bottom of the light guide plate of the liquid crystal display is printed with white dots. At the position where the light guide plate is printed with the mesh points, the light rays are not regularly reflected totally but emitted to the upper part of the light guide plate. Controlling the density of the dots at each position can control how much light is emitted from the light guide plate at that position. The precisely designed mesh points of the light guide plate can enable light rays incident from two sides to be uniformly spread on the whole plane. Optical films are placed above the light guide plate, and the films play a role in homogenizing light and converging large-angle light for front observation and the like.

The side-in backlight source adopts the optical element of the light guide plate, so that the side-in backlight source can be made very thin, and the thinning development of the LCD display is facilitated. However, due to the introduction of the light guide plate, the LED generates a large amount of heat during the illumination process, so that the temperature in the narrow cavity of the side-in type backlight source is too high, and the warping problem of the light guide plate is further caused, thereby greatly reducing the lighting effect of the existing side-in type backlight source. Further, as the material of the light guide plate ages, it will produce extinction at a specific emission wavelength, which will further affect the display color. And the production cost is increased due to the complicated optical structure. There is therefore a need for a new type of side-entry backlight to ameliorate the above problems.

Disclosure of Invention

The invention aims to provide a lateral-entrance type backlight source and a display device thereof, which can solve the problems of reduced lighting effect, poor display color, high cost and the like in the existing lateral-entrance type backlight source.

In order to solve the above problem, an embodiment of the present invention provides a side-in backlight, which includes a substrate and a light collector disposed on the substrate. Wherein the optical concentrator comprises: the device comprises a support, a light source, a first reflecting piece, a second reflecting piece and a connecting frame. The first reflecting piece is in a round table shape, and the outer side surface of the first reflecting piece is a first reflecting surface; the second reflecting piece is arranged on the bracket, the second reflecting piece is in a round table shape, and the inner side surface of the second reflecting piece is a second reflecting surface; the first reflecting piece is fixed on the second reflecting piece through the connecting frame.

Further, a protruding portion is arranged on the support, a containing groove with an opening in the surface and being recessed downwards is arranged in the protruding portion, and the light source is arranged at the bottom of the containing groove.

Further, the bracket is further provided with an optical fiber lens, and the optical fiber lens is arranged in the accommodating groove.

Further, the first reflecting member, the second reflecting member, the light source and the fiber lens are coaxially arranged.

Further, a notch is formed in the upper bottom surface of the first reflecting member, and the notch and the projection of the light source on the upper bottom surface of the first reflecting member are overlapped.

Further, the composition material of the first reflecting member and the second reflecting member comprises one or more of polycarbonate, polymethyl methacrylate and K9 glass.

Further, the lateral backlight source comprises two substrates, the two substrates are arranged in parallel and opposite to each other, and the two substrates are provided with the light collectors.

Further, the side-in backlight source further comprises a diffuse reflection back plate, and the diffuse reflection back plate is arranged above the substrate.

Further, the side-in backlight source further comprises a double-sided prism diffuser plate disposed below the substrate.

Another embodiment of the present invention further provides a display device, which includes the side-entry backlight according to the present invention.

The invention has the advantages that: the invention relates to a side-entering backlight source and a display device thereof, which firstly utilize a notch on the upper bottom surface of a first reflecting piece to pass light rays with a very small angle which are primarily converged by an optical fiber lens, and utilize an optical fiber lens of a condenser to primarily couple the light rays emitted by an LED, primarily compress a large-angle lambertian light source emitted by the LED into a small angle, primarily reflect the large-angle lambertian light source which is primarily coupled by the optical fiber lens by utilizing a first reflecting surface, secondarily reflect incident light rays by utilizing a second reflecting surface, and finally obtain emergent light with a small angle, thereby avoiding the use of a light guide plate, reducing the production cost and avoiding the influence of the thermal warping problem of the light guide plate on the optical performance. Secondly, diffusing the light incident to the surface along all directions by using a diffuse reflection backboard, so as to play a role of homogenizing the light; utilize two-sided prism diffuser plate to spread the light that incides the surface, avoid the glancing light angle too big and serious fei nieer reflection problem that leads to, increase luminous efficacy, increase light homogeneity.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a side-in backlight of the present invention.

FIG. 2 is a schematic diagram of a concentrator in a side-entry backlight according to the present invention.

FIG. 3 is a schematic view of light rays in a condenser in a side-entry backlight according to the present invention.

The components in the figure are identified as follows:

100. side-in backlight

1. Substrate 2 concentrator

3. Diffuse reflection backboard 4 and double-sided prism diffusion plate

21. Support 22, light source

23. Fiber lens 24, first reflector

25. Second reflecting member 26, connecting frame

241. First and

second reflection surfaces

251 and 251

Detailed Description

The following detailed description of the preferred embodiments of the present invention is provided to enable those skilled in the art to make and use the present invention in a complete manner, and is provided for illustration of the technical disclosure of the present invention so that the technical disclosure of the present invention will be more clearly understood and appreciated by those skilled in the art how to implement the present invention. The present invention may, however, be embodied in many different forms of embodiment, and the scope of the present invention should not be construed as limited to the embodiment set forth herein, but rather construed as being limited only by the following description of the embodiment.

The directional terms used in the present invention, such as "up", "down", "front", "back", "left", "right", "inner", "outer", "side", etc., are only directions in the drawings, and are used for explaining and explaining the present invention, but not for limiting the scope of the present invention.

In the drawings, structurally identical elements are represented by like reference numerals, and structurally or functionally similar elements are represented by like reference numerals throughout the several views. In addition, the size and thickness of each component shown in the drawings are arbitrarily illustrated for convenience of understanding and description, and the present invention is not limited to the size and thickness of each component.

When certain components are described as being "on" another component, the component can be directly on the other component; there may also be an intermediate component disposed on the intermediate component and the intermediate component disposed on another component. When an element is referred to as being "mounted to" or "connected to" another element, they are directly "mounted to" or "connected to" the other element or "mounted to" or "connected to" the other element through an intermediate element.

Example 1

As shown in fig. 1, the side-in backlight of the present embodiment includes two substrates 1, a light collector 2, a diffuse reflection back plate 3, and a double-sided prism diffuser plate 4. Wherein the two substrates 1 are arranged parallel to each other; the condenser 2 is disposed on the substrate 1.

As shown in fig. 2, wherein the condenser 2 comprises: a bracket 21, a light source 22, a fiber lens 23, a first reflector 24, and a second reflector 25.

As shown in fig. 2, a protrusion is disposed on the bracket 21, wherein a receiving groove with an open surface and a downward recess is disposed in the protrusion, the light source 22 is disposed at the bottom of the receiving groove, and the fiber lens 23 is disposed in the receiving groove. Wherein the first reflector 24, the second reflector 25, the light source 22 and the fiber lens 23 are coaxially arranged. Therefore, the light rays are reflected in the condenser for multiple times, and the light condensing effect is realized.

As shown in fig. 2, the first reflector 24 has a truncated cone shape, and an outer side surface of the first reflector 24 is a first reflecting surface 241; the second reflecting member 25 is disposed on the bracket 21, the second reflecting member 25 is in a truncated cone shape, and an inner side surface of the second reflecting member 25 is a second reflecting surface 251; the first reflector 24 is fixed to the second reflector 25 by the connecting frame 26, wherein the connecting frame 26 is made of a material with excellent light transmittance, so that the light reflected by the second reflecting surface 251 can pass through. Wherein, the upper bottom surface of the first reflector 24 is provided with a notch, and the notch and the projection of the light source 22 on the upper bottom surface of the first reflector 24 are mutually overlapped. Therefore, the small-angle light emitted by the light source 22 can penetrate through the fiber lens 23 and then directly exit through the notch.

As shown in fig. 3, the light emitted from the light source 22 is divided into two parts, one part is the small-angle light after the primary coupling by the fiber lens 23 directly emitted through the notch on the upper bottom surface of the first reflector 24; the other part is that the large-angle lambertian light source after being primarily coupled by the fiber lens 23 is primarily compressed into a small angle to be primarily reflected on the first reflecting surface 241, then the first reflecting surface 241 reflects the light to the second reflecting surface 251 for secondary reflection, and finally the light is converted into small-angle light to be emitted, so that a large glancing light emitting area is obtained, a light guide plate is avoided, the production cost is reduced, and the influence of the thermal warping problem of the light guide plate on the optical performance is avoided.

The light source 22 may be an LED chip, and thus the formed light source 22 is more efficient, more stable, and has excellent tolerance and high brightness of emitted light.

Wherein the first reflecting surface 24 and the second reflecting surface 25 are made of one or more materials selected from Polycarbonate (PC), polymethyl methacrylate (PMMA) and K9 glass. The first reflecting surface 24 and the second reflecting surface 25 formed by the method have high light transmittance and good ultraviolet resistance effect.

Wherein, 1 number of the optical collectors 2 can be arranged on the substrate 1, and 2 or more optical collectors 2 can also be arranged. The number of concentrators 2 can thus be determined on a case-by-case basis, thereby controlling production costs.

Wherein the diffuse reflection back plate 3 is arranged above the two substrates 1; the constituent material of the diffuse reflection back plate 3 includes one or more of Polycarbonate (PC), polymethyl methacrylate (PMMA) and K9 glass. Therefore, the light incident to the surface of the diffuse reflection backboard 3 is diffused along all directions, and the effect of uniform light emitting is achieved.

The double-sided prism diffusion plate 4 and the diffuse reflection back plate 3 are arranged below the two substrates 1 in parallel; the double-sided prism diffusion plate 4 is made of one or more of Polycarbonate (PC), polymethyl methacrylate (PMMA) and K9 glass. Therefore, the large-angle light rays incident to the surface of the double-sided prism diffusion plate 4 are refracted for many times through the two prism surfaces to become small-angle light rays, the problem of Fresnel reflection caused by the emergence of the large-angle light rays is avoided, the light energy loss is avoided, the light emitting efficiency is improved, and the light uniformity is improved.

Another embodiment of the present invention further provides a display device, which includes the side-in backlight 100 of the present invention.

The side-in backlight and the display device thereof provided by the invention are described in detail above. It should be understood that the exemplary embodiments described herein should be considered merely illustrative for facilitating understanding of the method of the present invention and its core ideas, and not restrictive. Descriptions of features or aspects in each exemplary embodiment should generally be considered as applicable to similar features or aspects in other exemplary embodiments. While the present invention has been described with reference to exemplary embodiments, various changes and modifications may be suggested to one skilled in the art. It is intended that the present invention cover the modifications and variations of this invention provided they come within the spirit and scope of the appended claims and their equivalents and improvements made thereto.

Claims

1. A side-entry backlight, comprising: the two substrates are oppositely arranged and are parallel to each other, and condensers are arranged on the two substrates;

the condenser includes:

a support;

a light source mounted on the bracket;

the first reflecting piece is in a round table shape, and the outer side surface of the first reflecting piece is a first reflecting surface;

the second reflecting piece is arranged on the bracket, the second reflecting piece is in a round table shape, and the inner side surface of the second reflecting piece is a second reflecting surface;

the first reflecting piece is fixed on the second reflecting piece through the connecting frame; and

the first reflecting piece, the second reflecting piece, the light source and the fiber lens are coaxially arranged;

a notch is formed in the upper bottom surface of the first reflecting piece, and the notch and the projection of the light source on the upper bottom surface of the first reflecting piece are mutually overlapped;

wherein, a part of light emitted by the light source is small-angle light, and the small-angle light is primarily coupled by the fiber lens and directly emitted out through a gap on the upper bottom surface of the first reflecting piece;

the other part of light emitted by the light source is large-angle lambertian-like light rays, the large-angle lambertian-like light rays are subjected to primary coupling through a fiber lens and are primarily compressed into small angles to be primarily reflected on the first reflecting surface, and then the first reflecting surface reflects the light rays to the second reflecting surface for secondary reflection;

the side-entry backlight further comprises:

the diffuse reflection back plate is arranged above the two substrates;

and the double-sided prism diffusion plate is arranged below the two substrates.

2. The lateral backlight according to claim 1, wherein the bracket has a protrusion, wherein the protrusion has a receiving groove with an opening on a surface and a recess downward, and the light source is disposed at a bottom of the receiving groove.

3. The side-entry backlight of claim 2, wherein the fiber lens is disposed in the receiving groove.

4. The edge-lit backlight of claim 1, wherein the first and second reflectors are formed from a material comprising one or more of polycarbonate, polymethyl methacrylate, and K9 glass.

5. A display device comprising the side-entry backlight of claim 1.