Optical: systems and elements – Lens – With variable magnification
Reexamination Certificate
2007-07-17
2009-02-24
Mack, Ricky (Department: 2873)
Optical: systems and elements
Lens
With variable magnification
C359S690000
Reexamination Certificate
active
07495842
ABSTRACT:
To provide a compact, high-performance zoom lens having a small lens aperture for enlarging an image from a light valve such as a DMD for forming an image by changing a reflecting direction of light and projecting the image so enlarged on to a screen or the like, the zoom lens includes, in order from a magnifying side, a first lens group having a positive or negative refractive power as a whole, a second lens group having a negative refractive power as a whole and a third lens group having a positive refractive power as a whole, wherein changing the magnification of a whole lens system thereof is attained by configuring such that while a magnification varying operation is in effect, the first lens group is left fixed, and the second lens group and the third lens group are made to move on the optical axis.
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“Digital Micromirror Device” downloaded from Wikipedia, the free encyclopedia, http://en.wikipedia.org/wiki/digital—micromirror—device., downloaded Jan. 3, 2008, 2 pages.
“DMD (Digital Micro-Mirror Device)”, About.com: Home Theater http://hometheater.about.com/od/televisionbasics/g/dmddef.htm?p=1, downloaded Jan. 3, 2008, 1 page.
“Thefreedictionary.com” Digital micromirror device—encyclopedia article about Digital micr . . . http://encyclopedia.thefreedictionary.com/p.Digital+micromirror+device, downloaded Jan. 3, 2008, 2 pages.
Kawakami Etsuro
Tejima Yasuyuki
Casio Computer Co. Ltd.
Frishauf Holtz Goodman & Chick P.C.
Greece James R
Mack Ricky
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