US 12,007,084 B2
Natural light homogenization lighting device and method based on free-form surface and sawtooth grating
Jian Liu, Harbin (CN); Xumin Ding, Harbin (CN); Xinwei Wang, Harbin (CN); and Chenguang Liu, Harbin (CN)
Assigned to GLORY LIGHT TECHNOLOGY CO., LTD., Harbin (CN)
Filed by GLORY LIGHT TECHNOLOGY CO., LTD., Harbin (CN)
Filed on Jan. 10, 2023, as Appl. No. 18/095,398.
Claims priority of application No. 202210028328.9 (CN), filed on Jan. 11, 2022.
Prior Publication US 2023/0220967 A1, Jul. 13, 2023
Int. Cl. F21S 11/00 (2006.01); F21V 5/02 (2006.01)
CPC F21S 11/002 (2013.01) [F21S 11/007 (2013.01); F21V 5/02 (2013.01)] 5 Claims
OG exemplary drawing
 
1. A natural light homogenization lighting device, comprising a front surface array and a rear surface array,
wherein the front surface array is a free-form surface array, the rear surface array is a sawtooth surface array, and the free-form surface array is configured to collect outdoor natural light, and to transmit the outdoor natural light to the sawtooth surface array through an intermediate medium; and
wherein the sawtooth surface array is configured to deflect the incident natural light to an indoor space after the outdoor natural light is refracted by an inclined surface;
wherein the lens form of the free-form surface array is a convex free-form surface or a concave free-form surface, the convex free-form surface or concave free-form surface faces the incident direction of natural light, and the normal of the lens surface forms an acute angle to the incident angle of natural light;
for the convex free-form surface, an expression of the thickness d 1 at different positions x1 and y1 is

OG Complex Work Unit Math
wherein n represents the refractive index, r represents the radius of curvature at the vertex of the convex free-form surface, ϑ3 represents a surface-type inclination angle of the convex free-form surface, which makes the light propagate in the horizontal direction through refraction, and the radius of curvature is 1-5 times the minimum spacing between the free-form surface and the sawtooth grating; for the concave free-form surface, an expression of the thickness d2 at different positions x1 and y1 on the concave free-form surface array is

OG Complex Work Unit Math
where n represents the refractive index, r represents the radius of curvature at the vertex of the concave free-form surface, and ϑ3 represents a surface-type inclination angle of the concave free-form surface, which makes the light propagate in the horizontal direction through refraction, and the radius of curvature is 1-5 times the minimum spacing between the free-form surface and the sawtooth grating.