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:
Apr. 21, 1998
Filed:
Oct. 29, 1996
Yasunori Ueno, Kawasaki, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Apparatus and methods for measuring refractive power and radius of curvature of a lens are disclosed. The apparatus comprises a refractive-power measurement subsystem in combination with a curvature-radius measurement subsystem. Each subsystem has its own optical axis and includes at least two point sources of light symmetrically situated relative to the respective optical axis in a plane perpendicular to the axis. Light fluxes from the light sources pass through or reflect from, respectively, the subject lens and impinge on a light-position sensor such as a CCD. The optical axes are preferably separate but become coaxial before reaching the light-position sensor. The refractive-index measurement subsystem senses the positions of images of the light sources on the light-position sensor as affected by refraction of light fluxes passing through the subject lens relative to positions of images obtained with no lens is being measured. The curvature-radius measurement subsystem senses the positions of images of the light sources as affected by reflection of light fluxes from the lens surface relative to positions of images obtained when the surface is planar.