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:
Jun. 02, 2020
Filed:
Mar. 23, 2018
Canon Kabushiki Kaisha, Tokyo, JP;
Mikio Kobayashi, Utsunomiya, JP;
Reona Ushigome, Saitama, JP;
Canon Kabushiki Kaisha, Tokyo, JP;
Abstract
A diffractive optical elementincludes a first diffraction grating, a second diffraction grating, filmsformed between the first diffraction gratingand the second diffraction grating. The DOEsatisfies a conditional expression of n<n<n, where nis an average refractive index of filmsformed between grating wall surfacesand grating wall surfacesat a wavelength of 550 nm, nis a refractive index of the first diffraction gratingat a wavelength of 550 nm, and nis a refractive index of the second diffraction gratingat a wavelength of 550 nm. The filmsand filmsthat are formed between grating surfacesand grating surfacessatisfy a predetermined relationship.