Backlight module and liquid-crystal display device

Abstract

The invention provides a backlight module and a liquid-crystal display device. A light-emitting device can be applied to a lateral-entrance backlight module without a light guide plate. The backlight module comprises an LED (Light-Emitting Diode) light source for providing backlight and an optical lens for aligning and emitting LED backlight within a certain angle. The optical lens comprises a bottom surface, a cambered surface opposite to the bottom surface, a vertical surface which is positioned on the two sides of the cambered surface and is connected with the connected with the cambered surface, and a slope which is connected with the bottom surface and the vertical surface, wherein the cambered surface, the vertical surface and the slope are all used for emitting the backlight provided by the LED light source. By adopting the novel optical device provided by the application, most backlight which is originally emitted from the near light side of the LED light source can reach the distance light side of the LED light source after being aligned at a certain degree and is emitted from one end of the distance light side, so that uniform light emitting in a display area is realized.

Description

technical field [0001] The invention relates to the field of liquid crystal television backlights, in particular to a backlight module and a liquid crystal display device. Background technique [0002] Existing backlight modules can be divided into direct-type and side-type backlight modules. In side-type backlight modules, since the LED light source is located at the edge of the backlight module, it is necessary to add a light guide plate so that part of the light path is in the light guide plate. Total reflection occurs on the surface, and at the same time, dots are set on the lower surface of the light guide plate to control the reflection angle of the light path, and then convert the point / line light source on the side into a uniform surface light source; however, adding a light guide plate also makes the process of side-type backlight modules more difficult. big. First of all, because the light guide plate is significantly affected by temperature, the optical structure...

AI Technical Summary

Problems solved by technology

[0002] Existing backlight modules can be divided into direct-type and side-type backlight modules. In side-type backlight modules, since the LED light source is located at the edge of the backlight module, it is necessary to add a light guide plate so that part of the light path is in the light guide plate. Total reflection occurs on the surface, and at the same time, dots are set on the lower surface of the light guide plate to control the reflection angle of the light path, and then convert the point / line light source on the side into a uniform surface light source; however, adding a light guide plate also makes the process of side-type backlight modules more difficult. Big

First of all, because the light guide plate is significantly affected by temperature, the optical structure processing of the light incident surface is very complicated; secondly, the lower surface of the light guide plate needs to be provided with dots for changing the reflection angle of the light path, and the design and printing process of the dots are relatively complicated. Moreover, the use of ink printing will also cause color cast phenomenon; at the same time, the setting of the light guide plate may also cause reliability problems, such as the problem of abrasion during the vibration test, the problem of crowded lamps in the high temperature test, etc.

[0003] However, in the side-lit backlight module, if the light guide plate is not used, most of the light paths of the backlight emitted by the LED light source will exit from the near light end of the light source, and only a few light paths can reach the far light end, resulting in near The light path at the light end is concentrated and the brightness is high, while the light path at the far light end is less and the brightness is darker, so the point / line light source emitted by the LED light source cannot be effectively converted into a uniform surface light source

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