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:
Jul. 07, 1981
Filed:
Mar. 20, 1979
Eric Saurer, Bevaix, CH;
Fereydoun Gharadjedaghi, Neuchatel, CH;
Claude Laesser, La Chaux-de-fonds, CH;
Rene Viennet, Neuchatel, CH;
Yves Ruedin, Saint-Blaise, CH;
Ebauches S.A., Neuchatel, CH;
Abstract
Electro-optic passive display cell constituted by a layer of a mixture of a nematic liquid crystal having a positive dielectric anisotropy, an optically active compound and dichroic molecules. The inner faces of the plates of the cell are covered with alignment layers such that, in the area situated outside the display zones or segments, the layer of the mixture has a homeotropic structure in its whole thickness. Opposite the segments the cell is arranged in such a way that the layer of the mixture has a helicoidal structure so that incident light is absorbed in these zones when the segments are not activated and that the layer of the mixture is orientated according to a homeotropic structure under the action of an electric field. Thus, when the cell is at rest, all its segments are visible. The display is effected by 'cancelling' or 'effacing' the segments which must not appear, so that only the non activated segments remaining visible in dark on a clear or transparent background.