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:
Mar. 26, 2002
Filed:
Jan. 28, 2000
Applicant:
Inventors:
Assignee:
Ricoh Company, Ltd., Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G03B 2/114 ; G02F 1/1335 ; G02F 1/1333 ; G02F 1/03 ; H04N 5/64 ;
U.S. Cl.
CPC ...
G03B 2/114 ; G02F 1/1335 ; G02F 1/1333 ; G02F 1/03 ; H04N 5/64 ;
Abstract
A projector is often positioned so that its optical axis is at an imperfect orthogonal angle with respect to a projection screen. This position causes a keystone distortion as well as imperfect focus in the projected image. To correct these undesirable problems, initially, a lens and/or an image-forming plate is independently repositioned to bring the projected image into focus based upon user input data. The keystone distortion is also corrected by redrawing the image on an image-forming surface based upon additional user input data.