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. 12, 2003
Filed:
Mar. 06, 1998
Jürg Fünfschilling, Basel, CH;
Martin Schadt, Seltisberg, CH;
Rolic AG, Zug, CH;
Abstract
A major disadvantage of known reflective displays consists in the fact that they ideally have a switching angle of ±45° in the so-called symmetric mode. With the liquid crystal mixtures known to date, this is not possible without hysteresis effects occurring even at small switching angles and resulting in the switching time being increased to an impermissible extent. The invention relates to a novel reflective, ferroelectric display which can be actuated without DC voltage and has a maximum switching angle &agr; which is ±22.5°. The liquid crystal display according to the invention is distinguished in particular by the fact that a further birefringent element is arranged between the two plates bounding the birefringent liquid crystal layer. In a first category of liquid crystal displays according to the invention, this additional birefringent element is a transparent plate having an optical path difference &Dgr;n·d≈&lgr;/4, which is arranged after the liquid crystal layer in the direction of the light incidence, in particular between said layer and the mirror.