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:
Sep. 05, 1989
Filed:
Nov. 21, 1988
Manami Saka, Osaka, JP;
Minolta Camera Kabushiki Kaisha, Osaka, JP;
Abstract
A collimator lens of a single lens type having a convex aspherical surface on the collimated light side and a plane surface on the condensed light side fulfills the following conditions: ##EQU1## wherein f represents a focal length of the collimator lens; t represents an axial distance of the collimator lens; NA represents a numerical aperture of the collimator lens; n represents a refractive index of the collimator lens; r represents a radius of curvature of the convex aspherical surface in the paraxial region. According to the collimator lens of a single lens type thus configurated, short axial distance and light weight can be realized, which makes it possible to be formed by the liquid glass drop method. In addition, the collimator lens of a single lens type which keeps good balance of an axial aberration and an off-axial aberration is obtainable.