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. 14, 2012
Filed:
Dec. 05, 2008
Masafumi Yokoyama, Itabashi-ku, JP;
Masafumi Yokoyama, Itabashi-ku, JP;
Citizen Holdings Co., Ltd., Tokyo, JP;
Abstract
The present invention is directed to the provision of a liquid crystal Fresnel lens that achieves high focusing performance. The liquid crystal Fresnel lens according to the present invention includes a concentrically segmented ring-shaped electrode group, a common electrode disposed opposite the ring-shaped electrode group, a liquid crystal layer provided between the ring-shaped electrode group and the common electrode, a first lens segment region which includes a first plurality of ring-shaped electrodes from the ring-shaped electrode group, and which forms a first retardation distribution by utilizing the first plurality of ring-shaped electrodes, and a second lens segment region which includes a second plurality of ring-shaped electrodes from the ring-shaped electrode group, the second plurality of ring-shaped electrodes being located outwardly of the first plurality of ring-shaped electrodes, and which forms a second retardation distribution by utilizing the second plurality of ring-shaped electrodes, wherein a Fresnel lens-like retardation distribution is formed across the first and second lens segment regions, and the number of the second plurality of ring-shaped electrodes is made smaller than the number of the first plurality of ring-shaped electrodes.