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. 17, 2009
Filed:
Mar. 12, 2007
Applicants:
Yi-hao Kang, Hsinchu, TW;
Chao-yi Yeh, Hsinchu, TW;
Inventors:
Yi-Hao Kang, Hsinchu, TW;
Chao-Yi Yeh, Hsinchu, TW;
Assignee:
Young Optics Inc., Hsinchu, TW;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 3/00 (2006.01); G02B 9/00 (2006.01); G02B 13/04 (2006.01);
U.S. Cl.
CPC ...
Abstract
A fixed-focus lens suitable for projecting an image beam from a light valve onto a screen is provided. The fixed-focus lens comprises a first lens group, a second lens group, and a third lens group arranged in sequence. The third lens group is disposed near the light valve. The first lens group having a negative refractive power comprises at least an aspheric lens. The second lens group having a positive refractive power comprises at least a lens. The third lens group having a positive refractive power comprises at least four lenses.