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:
Jun. 09, 2009
Filed:
Jan. 04, 2008
Kenzaburo Suzuki, Yokohama, JP;
Kenzaburo Suzuki, Yokohama, JP;
Nikon Corporation, Tokyo, JP;
Abstract
A projector optical system for forming a real image by projecting an image of a display element has, sequentially from a screen side or an observation side, a first lens group having positive refractive power, an aperture diaphragm, a second lens group, and a third lens group having positive refractive power, with a diffractive optical element being provided on at least one of the first lens group and the second lens group which are adjacent to the aperture diaphragm. The projector optical system satisfies:0.05<0.9wherein G is an air gap on the optical axis between the second lens group and the third lens group, and L is a length on the optical axis, from the surface that is closest to the screen side to the display element.