Backlight unit used for local light adjustment and luminous flux control member

Abstract

A backlight unit capable of suppressing a white spot phenomenon by uniformly diffusing light emitted from a light source is provided. The backlight unit includes a light guide plate including a firstmain surface and a second main surface facing the first main surface, a concave light receiving part formed on the first main surface, a light quantity adjusting concave part formed on the second mainsurface, and a light quantity adjusting sheet on the light quantity adjusting concave part and the second main surface therearound. The backlight unit includes a substrate provided with a plurality of light emitting elements; a plurality of light beam control parts arranged on the substrate in a manner of being corresponding to the light emitting elements and transmitting light dispersed by the light source to the upper part uniformly; and a shielding film disposed between the luminous flux control members and reflecting at least a part of light emitted by the luminous flux control members.

Description

technical field [0001] The present invention relates to a backlight unit and a light beam control component for local dimming, and more specifically, to a backlight unit and a light beam control component with a wide light diffusion area and capable of local dimming. Background technique [0002] Unlike OLEDs, which emit light by themselves, displays that do not emit light themselves, like LCDs, are supplied with light from a backlight unit located behind the display. [0003] Backlight units using LEDs are roughly classified into edge type and direct type according to the installation position of the LED light source. [0004] As for the direct-type backlight unit, a reflective sheet is provided on the upper part of the substrate (for example, PCB) on which a plurality of LED arrays composed of a plurality of LEDs are arranged, and a light guide member, a diffusion sheet, Prism sheet and protective sheet. The substrate (for example, PCB), reflection sheet, light guide mem...

AI Technical Summary

Problems solved by technology

[0006] However, in the direct type backlight unit, since the LED is located directly below the light irradiation area in the screen display area of ​​the liquid crystal display device LCD, the position of the LED in the corresponding light irradiation area is displayed more clearly than other areas. Bright white spot (White spot) phenomenon

Therefore, in the case of the direct type backlight unit, there is a limitation that in order to suppress the white point phenomenon and diffuse the light emitted from the LED to the light irradiation area sufficiently and uniformly, it is necessary to provide The air gap (Air gap) for light diffusion, the design of increasing the thickness of the light guide member, etc., and there is also a limitation in making the thickness of the backlight unit ultra-thin

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