The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 03, 1995
Filed:
Feb. 06, 1995
Applicant:
Inventors:
Sakae Houryu, Hachiohji, JP;
Kenji Saitoh, Atsugi, JP;
Assignee:
Canon Kabushiki Kaisha, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01B / ; G01N / ;
U.S. Cl.
CPC ...
356401 ; 356375 ; 250548 ;
Abstract
A position detecting system includes a light source for producing a light beam for irradiating a reference mark formed on an object which is relatively displaceable relative to the light beam, a detector for detecting a light quantity distribution of the light from the reference mark, and a circuit for comparing a first light quantity distribution at a first position with a second light quantity distribution at a second position spaced from the first position by a predetermined distance, and for determining a reference position of the object on the basis of the comparison.