US 12,216,257 B2
Plastic light-folding element, imaging lens assembly module and electronic device
Pei-Chi Chang, Taichung (TW); Wei-Chun Lo, Taichung (TW); Po-Lun Hsu, Taichung (TW); Lin-An Chang, Taichung (TW); and Ming-Ta Chou, Taichung (TW)
Assigned to LARGAN PRECISION CO., LTD., Taichung (TW)
Filed by LARGAN PRECISION CO., LTD., Taichung (TW)
Filed on Jan. 14, 2022, as Appl. No. 17/575,713.
Claims priority of provisional application 63/145,049, filed on Feb. 3, 2021.
Prior Publication US 2022/0244507 A1, Aug. 4, 2022
Int. Cl. G02B 13/00 (2006.01); B29C 45/00 (2006.01); B29D 11/00 (2006.01)
CPC G02B 13/0065 (2013.01) [G02B 13/007 (2013.01); B29C 2045/0027 (2013.01); B29D 11/0074 (2013.01)] 16 Claims
OG exemplary drawing
 
1. A plastic light-folding element, comprising:
an incident surface configured to let an imaging light enter the plastic light-folding element;
an exit surface configured to let the imaging light exit the plastic light-folding element;
at least one reflective surface configured to fold the imaging light;
at least one connecting surface connected to the incident surface, the exit surface and the at least one reflective surface; and
at least one gate vestige structure disposed on the at least one connecting surface;
wherein each of the incident surface, the exit surface and the at least one reflective surface comprises an optical portion and an arc step structure, each of the arc step structures is disposed on a periphery of each of the optical portions, and an arc is formed by each of the arc step structures centered on each of the optical portions;
wherein an area of the at least one gate vestige structure on the at least one connecting surface is Ag, a total area of the at least one connecting surface is At, a step height of each of the arc step structures is h, and the following conditions are satisfied:
33%≤Ag/At≤90%; and
0.003 mm≤h≤0.17 mm.