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. 02, 1980
Filed:
Jul. 10, 1979
Applicant:
Inventors:
Assignee:
Hitachi, Ltd., , JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B43L / ;
U.S. Cl.
CPC ...
33 1 / ; 33 2 / ; 33 2 / ; 33 2 / ;
Abstract
A device for the fabrication of a concave diffraction grating wherein grating grooves are mechanically ruled on a spherical surface of a diffraction grating blank and wherein a tool for ruling the grating grooves is reciprocated along the spherical surface of the diffraction grating blank, guided by a cylindrical cam, to form grooves having a uniform sectional shape over their whole area, whereby a concave diffraction grating of high diffraction efficiency and little scattering light is fabricated.