Patents Examined by K. F. Hantis - Justia Patents Search

Patents Examined by K. F. Hantis

Method of positioning a wafer with respect to a focal plane of an optical system

Patent number: 5268744

Abstract: A method of positioning a surface of a wafer with respect to a focal plane of an optical system is disclosed.

Type: Grant

Filed: April 4, 1991

Date of Patent: December 7, 1993

Assignee: Canon Kabushiki Kaisha

Inventors: Tetsuya Mori, Akiyoshi Suzuki