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. 22, 2004
Filed:
Oct. 23, 2001
Sony Corporation, Tokyo, JP;
Abstract
The present invention provides an optical switch for making part of incident light, which has been made incident on an optical waveguide, selectively emergent to a light emergence portion provided outside the optical waveguide. The optical switch includes a liquid crystal device for selective emergence of the incident light. An arbitrary layer of the liquid crystal device is set such that letting &Dgr;n be a difference between a refractive index n of the optical waveguide and a refractive index n of the arbitrary layer of the liquid crystal device, “d” be a thickness of the arbitrary layer, and &lgr; be a wavelength of the incident light, the values of &Dgr;n, “d”, and &lgr; satisfy a condition of 2.20×10 ≦|&Dgr;n·d·&lgr; |≦3.03×10 . With this optical switch, the uniformity of a light emergence efficiency can be easily realized by making use of a small change region in which the light emergence efficiency is not largely varied. The present invention also provides a display unit using the optical switches.