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:
Oct. 22, 2002
Filed:
Jun. 29, 2001
Applicant:
Inventors:
Noboru Ebizuka, Yokohama, JP;
Masanori Iye, Tokyo, JP;
Koji Sugioka, Wako, JP;
Toshikazu Ebisuzaki, Wako, JP;
Assignee:
Riken, Saitama, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B 5/04 ;
U.S. Cl.
CPC ...
G02B 5/04 ;
Abstract
In order to provide a grism wherein even if the vertex angle of a prism increases, it does not exceed its critical angle, besides, which can elevate its efficiency, and mass-production of which is possible, whereby reduction in cost of which can be realized. The grism comprises a first prism having a high refractive index, a second prism having a high refractive index, and a volume phase grating used for a diffraction grating; and the vertex angle of the first prism being opposed to the vertex angle of the second prism so as to sandwich the volume phase grating between the first prism and the second prism.