公开(公告)号：US11808612B2

公开(公告)日：2023-11-07

申请号：US17298974

申请日：2019-03-15

Applicant: HARMONIC DRIVE SYSTEMS INC.

Inventor： Shintaro Ueno ,  Yoshinori Shibahara ,  Sadaharu Kanamori

IPC: G01B11/26 ,  G01D5/347 ,  H02K1/22

CPC classification number: G01D5/3473 ,  H02K1/22

Abstract: In this optical rotary encoder, detection tracks of a rotating disc are irradiated with detection light emitted from a light-emitting element. An optical signal obtained via slits in the detection tracks passes through a slit pattern in a fixed slit plate and is received by light-receiving surfaces of a light-receiving element. The slit pattern in the fixed slit plate is formed so as to fit into a range of an effective spot of the detection light. An LED or other light-emitting element that has a small effective spot diameter can be used, which is advantageous in terms of reducing costs and making the device more compact.