公开(公告)号：US20230043860A1

公开(公告)日：2023-02-09

申请号：US17505873

申请日：2021-10-20

Applicant: Union Optech Co., Ltd.

Inventor： Yuancai LI ,  Liwei QUAN ,  Shoulin LI ,  Hao WANG

IPC: G02B13/24 ,  G02B13/00 ,  G03B21/53 ,  H04N9/31

Abstract: Disclosed is an ultra-short focus projecting optical system, which includes a display unit, a first lens group having a positive focus power, a second lens group having a positive focus power, a third lens group having a negative focus power, and an aspherical reflector arranged sequentially along a projection direction. The first lens group includes a first lens, a second lens and a diaphragm arranged sequentially along the projection direction. The first lens is a glass aspherical lens, the second lens is a glass spherical lens, and the first lens and the second lens are bent toward the diaphragm from their respective centers to their respective peripheries. The ultra-short focus projecting optical system and a projection device provided by this application can realize a large aperture and high resolution.