Vertical back light module

Abstract

The vertical back light module includes one reflecting plate, one diffusion plate, lamp tubes and one light diverging device. The diffusion plate is set on reflecting plate to form one holding chamber in between for holding the lamp tubes, and the light diverging device is set between the lamp tubes and the diffusion plate. The light diverging device may be one lens assembly including convex lenses corresponding to the lamp tubes separately, or one light conducting plate with refraction index gradually increased from the center to sides, or one prismatic lens.

Description

【Technical field】 [0001] The invention relates to a direct type backlight module. 【Background technique】 [0002] In recent years, with the colorization and enlargement of liquid crystal displays, their application fields are more extensive, such as notebook computers, various desktop computers, and LCD TVs. [0003] Since the liquid crystal display panel itself cannot emit light, it is a passive component and needs to use a light source system, such as a backlight module (Backlight Module), to provide a side light source for it to display screen images. [0004] A prior art direct-type backlight module is shown in FIG. 1. The direct-type backlight module 10 includes a diffuser 11 and a reflector 12, and a chamber 13 is formed between the reflector 12 and the diffuser 11. , a plurality of lamp tubes 14 are arranged in the chamber 13 . The lamp tube 14 is a cold cathode fluorescent lamp (CCFL), and the light emitted by it is diffused by the diffuser plate 11 and then projec...

AI Technical Summary

Problems solved by technology

[0005] Because the light of cold cathode fluorescent lamps is anisotropic, and when the number of lamp tubes 14 is small, due to the high reflection effect of the reflector 12, when the backlight module 10 is turned on, the lamp tubes 14 will diffuse in the space above it. The position facing the lamp tube 14 on the board 11 has a higher brightness, and other positions have a lower brightness, thus reflecting the bright bands of the display, making the display brightness of the liquid crystal panel uneven and causing display defects. Figure 2 shows a schematic diagram of the bright bands. The dotted line in the figure shows the lamp tube located under the diffusion plate 11, and the bright band 15 is the area shown by the solid line in the figure

[0006] In order to eliminate this phenomenon and make the light shine to a larger area, it is necessary to increase the distance between the lamp tube 14 and the diffuser plate 11, which makes the volume of the direct-type backlight module 10 larger, which cannot satisfy thin requirements

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