公开(公告)号：US3578979A

公开(公告)日：1971-05-18

申请号：US3578979D

申请日：1968-12-18

Applicant: TAJIMA SEISAKUSHO KK

Inventor： KAWAGUCHI TOSHIJI ,  TANAKA TAKEO ,  OKADA MASARU

IPC: G01D5/347 ,  G01B11/04 ,  H01J39/02

CPC classification number: G01D5/34715

Abstract: When a scale grid undergoes movement relative to index grids superposed on and adhering to respective photoelectric devices, the resulting variation in a bright-dark pattern formed by the grids is detected by the photoelectric devices and converted into electrical signals, which are processed and digitally displayed or utilized for control of machines and equipment.