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:
Feb. 06, 2018
Filed:
Jun. 02, 2017
Seiko Epson Corporation, Tokyo, JP;
Naoto Takehana, Matsumoto, JP;
Nobutaka Minefuji, Azumino, JP;
SEIKO EPSON CORPORATION, Tokyo, JP;
Abstract
A projector used a projection lens to enlarge and project image light generated by image generator. When it is assumed that the on-optical-axis position of a lens surface where the maximum of light ray passage ranges (effective diameter) is minimized in the projection lens is a minimum diameter position, a stop is provided on a lens shifted from the minimum diameter position toward the light exiting side. The lens on which the stop is provided is a lens (for example, fourth lens closest to minimum diameter position) that satisfies 0.8φ≦φ≦φ, where φrepresents the light flux diameter on a surface where the on-axis light flux diameter is maximized, and φis the diameter of the stop.