Optical lens
AssigneeRays Optics Inc.
InventorsBing-Ju Chiang, Yuan-Hung Su, Kuo-Chuan Wang
Life of this patent
Estimating the term…
Abstract
An optical lens includes a first lens group having negative refractive power, a second lens group having positive refractive power, and an aperture stop disposed between the first lens group and the second lens group. A total number of lenses of the two lens groups is less than 9. The first lens group has at least three lenses with refractive power and at least one aspheric lens. The second lens group has at least three lenses with refractive power and at least one aspheric lens. The first lens group includes a lens having positive refractive power and an Abbe number of smaller than 20.
Claims18
An optical lens, comprising:
- a first lens group with negative refractive power comprising at least three lenses with refractive powers, the at least three lenses with refractive powers including at least one aspheric lens, and the first lens group having a lens with positive refractive power and an Abbe number of smaller than 20;
- a second lens group with positive refractive power comprising at least three lenses with refractive powers, the at least three lenses with refractive powers including at least one aspheric lens, and a total number of lenses in the first lens group and the second lens group being less than 9, wherein each of the first lens group and the second lens group comprises a lens having a refractive index variation as a function of temperature (dn/dt) of smaller than −80 ×10−6 K−1;
- and
- an aperture stop disposed between the two lens groups.
Dependencies are inferred from the claim text.