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:
Nov. 07, 2000
Filed:
Mar. 03, 1998
Makoto Iwaki, Tokyo, JP;
Haruyuki Ohashi, Tokyo, JP;
Asahi Kogaku Kogyo Kabushiki Kaisha, Tokyo, JP;
Abstract
A plastic lens which can be positioned correctly during lens mounting. The plastic lens is used as a pickup lens on an optical head for an optical disk and it has a lens portion in the center with an annular rim formed on the periphery. The rim has two opposed surfaces, one of which provides a reference plane to effect positioning for fixing the plastic lens in a lens holder. The rim has a gate portion which remains to project from the periphery after a molten plastic material was injected through the corresponding channel during molding. The gate portion is cut off by a pair of cutting blades which are moved to come closer to each other in a direction substantially parallel to the optical axis of the lens portion. As the result of the cutting operation, a bur occurs at a distal end of the gate portion and it projects in a direction parallel to a plane orthogonal to the optical axis.