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:
Dec. 10, 1985
Filed:
Mar. 26, 1982
Keisuke Kikuchi, Ibaraki, JP;
Takitaro Morikawa, Sayama, JP;
Junichi Shimada, Ibaraki, JP;
Kenjiro Sakurai, Tokyo, JP;
Agency of Industrial Science & Technology, Tokyo, JP;
Ministry of International Trade & Industry, Tokyo, JP;
Abstract
A spherical lens of graded refractive index distribution comprises a core of uneven refractive index of the shape of a sphere or hemisphere and a clad of the shape of a spherical shell and a rod clad, with the two clads disposed on the periphery of the core. By the combination of the core showing negative aberration characteristic and the spherical-shell type clad and the rod clad both showing positive aberration characteristic, there can be formed a lens of corrected aberration. This lens suits combination or integration with other elements and permits easy manufacture of clads. It also provides effective convergence of beams of light desirable for use in an optical pickup, for example.