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:
Sep. 22, 2020
Filed:
Oct. 26, 2017
Olympus Corporation, Hachioji-shi, Tokyo, JP;
Koji Matsumoto, Tokyo, JP;
OLYMPUS CORPORATION, Tokyo, JP;
Abstract
An interference fringe generating optical system generates an interference fringe, and a magnifying optical system magnifies the interference fringe and projects the interference fringe on an object surface. The magnifying optical system includes an incident-side lens group on the side where a light beam forming the interference fringe is incident and an exit-side lens group on the side where the light beam is emitted and the interference fringe is projected towards the object surface. The expression f1/f2>3 holds, where f1 is the focal length of the incident-side lens group, and f2 is the focal length of the exit-side lens group. The incident-side and exit-side lens groups each have a positive refractive power. The expression xd/(f1+f2)<2 is satisfied, where xd is the distance from the exit-side principal point of the incident-side lens group to the incident-side principal point of the exit-side lens group.