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. 16, 1991
Filed:
Dec. 17, 1988
Masanori Iida, Nara, JP;
Kiyokazu Hagiwara, Hirakata, JP;
Hiroyuki Asakura, Osaka, JP;
Minoru Nishioka, Kobe, JP;
Koichi Murase, Neyagawa, JP;
Matsushita Electric Industrial Co., Ltd., Osaka, JP;
Abstract
A diffraction grating has a reflection film formed on a photosensitive layer disposed on a substrate through exposure followed by development and the groove profile thus formed has a configuration distorted from a sinusoidal form because the sensitivity curve of the photosensitive layer is of the second order non-linearity to the exposure amount. With the groove pitch expressed by d, K=2 .pi./d, the coordinate perpendicular to the groove direction taken as x, and the groove profile .eta.(x) expressed as .eta.(x)=h [sin (Kx)+.gamma.sin (2Kz-90.degree.)], the parameters h, .gamma. and .phi. satisfy as follows: