US 12,253,707 B2
Light guide element and backlight module
Ying-Hsiang Chen, Hsin-Chu (TW); Cheng-Yi Tseng, Hsin-Chu (TW); Chung-Yang Fang, Hsin-Chu (TW); and Ping-Yen Chen, Hsin-Chu (TW)
Assigned to Coretronic Corporation, Hsin-Chu (TW)
Filed by Coretronic Corporation, Hsin-Chu (TW)
Filed on Mar. 13, 2023, as Appl. No. 18/183,118.
Claims priority of application No. 202210305170.5 (CN), filed on Mar. 25, 2022.
Prior Publication US 2023/0305215 A1, Sep. 28, 2023
Int. Cl. F21V 8/00 (2006.01)
CPC G02B 6/0043 (2013.01) 23 Claims
OG exemplary drawing
 
1. A light guide element, comprising
a main body having a bottom surface, a light emitting surface opposite to the bottom surface, and a light incident surface connected between the light emitting surface and the bottom surface;
a plurality of first optical microstructures disposed on the bottom surface, each of the first optical microstructures having a first surface, wherein the first surface is configured to deflect a light beam out of the light emitting surface, a first acute angle is included between the first surface and the bottom surface, the first acute angle is a first angle of the first optical microstructures, and an angle value of the first angle is V1, where V1>0; and
a plurality of second optical microstructures disposed on the bottom surface, at least one of the second optical microstructures disposed between adjacent two of the first optical microstructures, the plurality of second optical microstructures comprising a plurality of sub-optical microstructures, wherein
a projection of each of the sub-optical microstructures on a reference plane perpendicular to the light incident surface has a peak point farthest from the bottom surface and a first valley point and a second valley point closest to the bottom surface, the peak point is located between the first valley point and the second valley point, a height difference between the peak point and one of the first valley point and the second valley point in a z-axis direction perpendicular to the bottom surface is ΔH, a length difference between the peak point and the one of the first valley point and the second valley point in a y-axis direction perpendicular to the light incident surface is ΔL, and a value obtained by tan−1(ΔH/ΔL) is V2, where V2>0 and V2≤0.5·V1 wherein an orthogonal projection of each of the sub-optical microstructures on the bottom surface comprises a curved pattern, the curved pattern comprises a first sub-curved pattern and a second sub-curved pattern respectively protruding toward opposite directions, and the plurality of first sub-curved patterns and the plurality of second sub-curved patterns of the plurality of sub-optical microstructures comprised in each of the second optical microstructures are alternately arranged and are connected to each other.