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:
Jan. 07, 1986
Filed:
Jan. 20, 1984
Yoshiyuki Asahara, Tokyo, JP;
Hiroshi Sakai, Tokyo, JP;
Seiichi Shingaki, Tokyo, JP;
Shigeaki Ohmi, Saitama, JP;
Hoya Corporation, Tokyo, JP;
Abstract
A process for the production of a slab-shaped lens having a gradient of refractive index only in the direction of thickness thereof is described, comprising stuffing a solution of dopant into micropores of a plate-shaped porous glass product with or without a heat-resistant film covered on both side surfaces thereof; unstuffing a part of the dopant to form a gradient of dopant concentration in the glass product; precipitating the dopant in the micropores; drying the porous glass product to evaporate the solvent remaining in the micropores; collapsing the micropores by applying a heat treatment to form a gradient of refractive index in the plate-shaped glass product; and when the side surfaces are not covered with the film, cutting off both side end portions of the plate-shaped glass product.