Backlight module

Abstract

The invention relates to a backlight module. The backlight module comprises a light guide plate, a light source, at least one membrane and at least one first adhesion layer, wherein the light guide plate extends along the X axis and the Y axis; the light source is provided with a light emitting face so as to provide light rays towards the light guide plate; the projection of the light emitting face on the X axis has the X axis length of the light emitting face, and the light emitting face is made to horizontally move towards the light guide plate along the Y axis so as to define a halo space; the membranes are arranged on the light guide plate; at least one part of the first adhesion layers is located in an Z axis projection area of the halo space; the first adhesion layers are used for adhering the membranes to the light guide plate; the interval between each first adhesion layer and the light emitting face on the Y axis is 2-3 mm; the projection of the part of each first adhesion layer on the X axis has the X axis length of the first adhesion layer and is smaller than the X axis length of the light emitting face. As the adhesion layers in front of the light emitting face of the light source adhere the optical membranes to the light guide plate, so that the halo phenomenon and the brightness performance are improved.

Description

technical field [0001] The invention relates to a backlight module, in particular to a backlight module for reducing the halo phenomenon on the light output side of a light source. Background technique [0002] With the evolution of technology and the improvement of specifications of notebook computers, luminous keyboards have gradually become the mainstream input devices of notebook computers. Illuminated keyboards are usually composed of an upper key module and a lower backlight module. Luminous brightness remains uniform. [0003] However, if figure 1 As shown, in the front of the light source 1001 of the backlight module in the prior art, usually because the optical film (such as the light-shielding sheet 1002 and / or the reflective sheet 1004) cannot tightly cover the upper / lower surface of the light guide plate 1006, There are gaps 1008 and 1009 between the upper / lower surface of the light guide plate 1006 and the light-shielding sheet 1002 and the reflection sheet 1...

AI Technical Summary

Problems solved by technology

[0003] However, if figure 1 As shown, in the front of the light source 1001 of the backlight module in the prior art, usually because the optical film (such as the light-shielding sheet 1002 and / or the reflective sheet 1004) cannot tightly cover the upper / lower surface of the light guide plate 1006, There are gaps 1008 and 1009 between the upper / lower surface of the light guide plate 1006 and the light-shielding sheet 1002 and the reflective sheet 1004, so that after the light emitted by the light source 1001 enters the light guide plate 1006, it will pass from the light guide plate 1006 adjacent to the gaps 1008 and 1009. / The light guide plate 1006 is lost from the lower surface, which will cause severe halo phenomenon at the gaps 1008 and 1009, which will lead to poor brightness performance of the luminous keyboard

On the contrary, if an adhesive is used to bond the light guide plate and the optical film in a large area to improve the tightness between the two, the light will not be able to flow properly because the refractive index of the adhesive is much higher than that of air. The internal transmission of the light guide plate will cause excessive light leakage on the surface of the light guide plate coated with adhesive, so that the optical brightness that can be output by the light guide plate far away from the light source is significantly reduced

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