Patent · US Active

Projection lens

US7952817B2 · kind B2 · utility

5Cited by
10References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJul 26, 2009
Grant dateMay 31, 2011
Priority date—
Expiry dateAug 10, 2029

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG02B13/16
  • WIPO fieldOptics
  • WIPO sectorInstruments

Abstract

A projection lens includes a first lens group with a negative refractive power, a second lens group with a negative refractive power, and a third lens group with a positive refractive power, wherein the second lens group is disposed between the first lens group and the third lens group. The first lens group includes an aspheric lens. The second lens group includes a first lens and a second lens. The third lens group includes a third lens, a forth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens, and a twelfth lens.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.