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:
May. 28, 2013
Filed:
Jun. 24, 2010
Tokuji Takizawa, Utsunomiya, JP;
Kazumi Kimura, Toda, JP;
Tokuji Takizawa, Utsunomiya, JP;
Kazumi Kimura, Toda, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
A concave reflection type diffraction optical element used for a Rowland type spectrometer, in which: the Rowland type spectrometer detects wavelengths in a range including a wavelength λor more and a wavelength λor less (λ<λ); the concave reflection type diffraction optical element has a diffractive efficiency D(λ) at a wavelength λ which shows local maximum and maximum value at a wavelength λsatisfying, the concave reflection type diffraction optical element includes a reference surface having an anamorphic shape; and the following condition is satisfied: R>r, where R indicates a meridional line curvature radius of the reference surface and r indicates a sagittal line curvature radius thereof.