CN201222148Y - Optical assembly of backlight module - Google Patents

Abstract

The utility model relates to an optical component of a backlight module, which is used in cooperation with a luminous source, wherein the optical component of the backlight module comprises a rectangular light-intensifying light guide plate and a prism sheet arranged on the light-intensifying light guide plate; the surface of the intensifying light guide plate is provided with a plurality of first prism units, the edge lines of the first prism units and the edge lines of the intensifying light guide plate form a preset included angle of non-0 degree, the prism sheet comprises a plurality of second prism units, and the edge lines of the second prism units are not parallel to the edge lines of the first prism units. The utility model discloses an optical assembly of backlight module via the prism piece with the mutual staggered crest line of first prism unit, thereby eliminate the interference ripple (moire) phenomenon of liquid crystal display panel when using.

Description

Optical components of the backlight module

technical field

The utility model relates to an optical component of a backlight module.

Background technique

The scale of the liquid crystal display (LCD) industry is expanding with the needs of consumers and the fierce competition among international manufacturers, so the research and development of related components is becoming more and more important; since LCD is not a self-illuminating display device, it must be achieved with the help of an external light source. Display effect, so the general LCD almost uses the backlight module.

The backlight module mainly provides a uniform and high-brightness light source for the LCD panel, and the basic principle of the backlight module is to convert the commonly used point or line light source into a high-brightness and uniform luminance surface light source product through a simple and effective light mechanism; With the improvement of liquid crystal display manufacturing technology and the trend of large size and low price, the backlight module needs to consider the market requirements of light weight, thinner, low power consumption, high brightness and lower cost.

Generally speaking, backlight modules can be mainly divided into: (1) side-light structure and (2) direct-light structure; in the side-light structure, the light source is a single light source placed on the side, and the light guide plate is Injection molding without printing design, light source design from the side, has the characteristics of light weight, thin, low power consumption, also used as light source for mobile phones, personal digital assistants (PDA), notebook computers and other products.

Referring to FIG. 1 , it is an exploded diagram of a known backlight module 200, which can be applied to a liquid crystal cell (Liquid Crystal Cell) 26, and mainly includes the following units.

(1) Light source 28

It must have the characteristics of high brightness and long life. Currently, there are cold cathode fluorescent tubes and hot cathode fluorescent tubes, light-emitting diodes (LEDs) and electroluminescence (ELs).

(2) Light Guiding Plate (LGP, Light Guiding Plate) 20

Applied to edge-lit backlight modules, it is an important component that affects light efficiency. The light guide plate 20 can be made of polymethyl methacrylate (PMMA) into a plate with a smooth surface by injection molding, and then use a material with high reflectivity and no light absorption to print a circle or a circle on the bottom of the light guide plate by screen printing. The square diffusion point 21 , when the light hits the diffusion point 21 on the bottom surface, the reflected light will diffuse to all angles, destroying the total reflection condition and emitting from the front of the light guide plate, so that the front of the light guide plate emits light evenly.

(3) Reflector (not shown in the figure)

Generally, the reflection plate of the edge-lit backlight module is placed at the bottom of the light guide plate to reflect back the light leaked from the bottom surface of the light guide plate 20 .

(4) Diffusion plate 22

The function of the diffuser is to provide a uniform surface light source for the liquid crystal display.

(5) Prism sheet (also known as brightness enhancement film) 24

The directivity of the light after the light is emitted from the diffuser plate 22 is poor, so the prism sheet 24 must be used to correct the direction of the light. The use efficiency of the light emitted from the diffusion plate 22 is increased. The prism sheet 24 can be made of polyester (Polyester) or polycarbonate (Polycarbonate) as a thin sheet with a thickness of about 150-230mm, and a long strip prism array (Prism) with a predetermined pitch (Pitch) and vertex angle is formed on the surface of the sheet Array), so that it has the effect of concentrating light.

As shown in FIG. 2 , when the light source is guided by the light guide plate 20 , it will be brightened and uniformed by the optical prism sheets 24 and 24 ′ before reaching the liquid crystal unit 26 . If the traveling light interferes when it reaches the liquid crystal cell 26, a moiré phenomenon will occur on the final liquid crystal panel. To solve this problem, the most commonly used method is to properly rotate the two prism sheets 24, 24' to break the regularity of the light path and improve it. However, the disadvantages of this solution are: 1. The two prism sheets 24, 24' will increase the cost; 2. The assembly man-hours increase and assembly tolerances accumulate.

Utility model content

In view of this, the main purpose of the present invention is to provide an optical assembly of a backlight module with low cost and simplified assembly.

In order to achieve the above-mentioned purpose, the optical assembly of the backlight module of the present utility model includes a light-increasing light guide plate of a rectangular plate, and a prism sheet located on the light-enhancing light guide plate; the light-enhancing light guide plate has a plurality of first prism units on its surface, In addition, the ridgeline of the first prism unit and the sideline of the light-enhanced light guide plate form a predetermined angle other than 0 degrees, and the prism sheet includes a large number of second prism units, and the ridgeline of the second prism unit and the The ridgelines of the first prism units are not parallel.

It can be seen from the above technical solutions that in the optical assembly of the backlight module of the present invention, the plurality of first prism units have been fabricated on the light-enhancing light guide plate, and the prism sheet is located on the light-enhancing light guide plate, and the prisms of the first prism units The extending direction of the line is not parallel to the extending direction of the ridge line of the second prism unit. Therefore, the optical assembly of the backlight module of the present invention is equivalent to provide two prism sheets that are staggered on the ridge line, so that the interference ripple (Morie) phenomenon can be eliminated under the manufacturing process that simplifies the assembly, and the cost can be reduced and the simplification can be achieved. The effect of assembly.

Description of drawings

FIG. 1 is an exploded schematic diagram of a known backlight module;

FIG. 2 is an exploded schematic view of some optical components of another known backlight module;

3 is an exploded schematic diagram of an optical assembly using the backlight module of the present invention;

FIG. 4 is a partially enlarged view of the light-enhancing light guide plate in the optical assembly of the backlight module of the present invention.

Explanation of reference signs

Backlight module 200

Light guide plate 20 Light source 28

Diffusion Point 21 Diffusion Plate 22

Prism sheet 24, 24' liquid crystal unit 26

Optical components 100

Enhanced light guide plate 10 First prism unit 11

Prism sheet 12 Second prism unit 13

LCD unit 16

First Direction S1 Second Direction S2

Scheduled angle A

Detailed ways

Please refer to FIG. 3 , which is an exploded view of an optical assembly using the backlight module of the present invention. The optical assembly 100 of the present invention is used on a backlight (not shown in the figure) to provide a surface light source for a liquid crystal unit 16 . The optical assembly 100 includes a light-enhancing light guide plate 10 and a prism sheet 12 disposed thereon. The enhanced light guide plate 10 is a rectangular plate. The enhanced light guide plate 10 has a plurality of first prism units 11 on its surface. These first prism units 11 are parallel to each other and have a predetermined distance and apex angle.

Please refer to FIG. 4 , which is a partially enlarged view of the light-enhancing light guide plate 10 in the optical assembly of the backlight module of the present invention. The ridge line of each first prism unit 11 extends along the first direction S1, and the first direction S1 and one side of the light enhancement light guide plate 10 form a predetermined angle A that is not 0 degrees (that is, neither parallel nor perpendicular to the increase angle). any side of the light guide plate 10), wherein the predetermined included angle A is 1-89 degrees.

Continue referring to FIG. 3 , the prism sheet 12 is located on the light-increasing light guide plate 10 and includes a plurality of second prism units 13; moreover, in order to eliminate the interference ripple (Morie) phenomenon, the ridge extension direction of these second prism units 13 (the second prism unit 13 The second direction S2) is not parallel to the extending direction of the ridgelines of the first prism units 11 (the first direction S1).

In the optical assembly of the backlight module of the present utility model, the plurality of first prism units 11 have been fabricated on the light enhancement light guide plate 10, and the prism sheet 12 is located on the light enhancement light guide plate 10; and the prisms of the first prism units 11 The extending direction of the line is not parallel to the extending direction of the ridge line of the second prism unit 13 . Therefore, the optical assembly of the backlight module of the present invention equivalently provides two prism sheets offset from each other on the ridge line, thereby eliminating the interference moire phenomenon under the manufacturing process of simplifying assembly.

The light-increasing light guide plate 10 in the above-mentioned optical assembly can be made of polymethyl methacrylate (PMMA) by injection molding, for example, and the prism sheet 12 can be made of polyester (Polyester) or polycarbonate (Polycarbonate). But the patent scope of the present utility model is not limited to the above-mentioned specific materials.

Claims (2)

1. An optical component of a backlight module used in conjunction with a light source, characterized in that the optical component includes: The enhanced light guide plate is a rectangular plate and includes a plurality of first prism units on its surface, the ridges of the first prism units form a predetermined angle other than 0 degrees with the sidelines of the enhanced light guide plate; and The prism sheet is located on the light-increasing light guide plate and includes a plurality of second prism units, the ridgelines of the second prism units are not parallel to the ridgelines of the first prism units. 2. The optical component of the backlight module according to claim 1, wherein the predetermined included angle is 1-89 degrees.

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