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. 21, 2002
Filed:
Jan. 31, 2001
Keiji Osawa, Tokyo, JP;
Nikon Corporation, Tokyo, JP;
Abstract
Light emitted from a taking lens enters a first birefringent plate la to be spatially divided along a first direction extending perpendicular to the direction in which the light advances to achieve two separate rays L and L . The vibrational planes of the two light fluxes L and L emitted from the first birefringent plate are converted to a circularly polarized light by a phase plate . The two light fluxes L ′ and L ′ emitted from the phase plate are each spatially divided into two by a second birefringent plate along a second direction extending perpendicular to the first direction to achieve four separate rays L , L , L and L , to be guided to an imaging plane of an imaging device . At least either the first birefringent plate or the second birefringent plate is constituted of lithium niobate, rutile. Chilean nitrate, or the like.