Patent Number: 6,169,636

Title: Focus corrector for zoom projection lenses used with pixelized panels

Abstract: A zoom projection lens for use with pixelized panels is provided. The projection lens has a negative/positive (retrofocus) form, with the positive lens unit (U2) having two positive subunits (U2.sub.S1, U2.sub.S2). The image (screen) side subunit (U2.sub.S1) serves as focus corrector for the lens, i.e., after zooming, this subunit is moved to adjust the focus of the lens. Compared to moving the negative unit (U1), this approach achieves better aberration correction and involves moving less mass through smaller distances.

Inventors: Kreitzer; Melvyn H. (Cincinnati, OH)

Assignee: U.S. Precision Lens Incorporated

International Classification: G02B 13/16 (20060101); G02B 13/22 (20060101); G02B 015/14 ()

Expiration Date: 01/02/2018