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:
Nov. 01, 2016
Filed:
Jan. 15, 2015
Nobuyuki Arai, Kanagawa, JP;
Nobuyuki Arai, Kanagawa, JP;
RICOH COMPANY, LTD., Tokyo, JP;
Abstract
An optical projection system enlarges an image on an image display element and projects the enlarged image onto a screen. The system includes the image display element, a first optical system including lens groups arranged in order from an image display element side, a lens barrel holding the lens groups, and a free-form surface lens rotationally asymmetric and made from plastic, and a second optical system including a curved mirror disposed after the first optical system, wherein the free-form surface lens is formed to decrease in thickness from an intersection point between a surface of the free-form surface lens and an optical axis of the first optical system to an outer periphery of the lens along a line extending to the outer periphery.