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:
Aug. 09, 2022
Filed:
Feb. 03, 2020
Canon Kabushiki Kaisha, Tokyo, JP;
Seiji Nakahara, Sakura, JP;
CANON KABUSHIKI KAISHA, Tokyo, JP;
Abstract
In order to provide an optical system to be installed in a projection system which is capable of allowing a patient to view a clear image in a diagnostic imaging apparatus, the optical system according to the present invention includes a Fresnel lens having a base material and a plurality of annular sections arranged around a center axis on a reference surface of the base material, and a deflection element configured to deflect light from the Fresnel lens. In a cross section including the center axis, an inclination angle of the annular sections to the reference surface changes asymmetrically between from a middle point of one and other ends of the Fresnel lens to the one end and from the middle point to the other end.