US 11,719,862 B2
Optical lens device for a head-mounted display, and method and mold for producing the same
Li-Jen Hsu, Yilan County (TW); Nan-Hung Kuo, Yilan (TW); Tsung-Hsien Wu, Hsinchu (TW); and Young-Cheng Chou, New Taipei (TW)
Assigned to OPTIVISION TECHNOLOGY INC., Hsinchu (TW)
Filed by Optivision Technology Inc., Hsinchu (TW)
Filed on Dec. 28, 2020, as Appl. No. 17/135,137.
Prior Publication US 2022/0206192 A1, Jun. 30, 2022
Int. Cl. G02B 3/08 (2006.01); G02B 1/04 (2006.01); B29D 11/00 (2006.01); G02B 1/14 (2015.01); B29K 33/00 (2006.01)
CPC G02B 3/08 (2013.01) [B29D 11/00269 (2013.01); G02B 1/041 (2013.01); G02B 1/14 (2015.01); B29K 2033/12 (2013.01)] 11 Claims
OG exemplary drawing
 
1. An optical lens device for a head-mounted display, comprising:
a transparent support substrate; and
a Fresnel lens disposed on said support substrate, and including a central lens element and a plurality of prismatic elements arranged relative to said central lens element in a proximal-to-distal manner, each of said prismatic elements having a base that faces toward said support substrate, and a draft facet and a sloped facet that extend from said base away from said support substrate to intersect with each other to form an apex, each of said prismatic elements having a height that is measured from said base to said apex and that is not greater than 75 μm, said base having a width that is not greater than 250 μm,
wherein each of said prismatic elements has a radius of curvature at said apex that is not greater than 2 μm;
wherein said draft facet of one of said prismatic elements intersects with said sloped facet of an adjacent one of said prismatic elements to form a groove nadir, a radius of curvature at said groove nadir being not greater than 2 μm; and
wherein said Fresnel lens is made from ultraviolet (UV)-curable resin.