Display device for optically representing information and a method of operation

US4327970A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Guenter Baur · Glückstadt, DE
• Hans Kohlmueller · Erlangen, DE
• Hans Krueger · Munich, DE

Key dates

• Filing date: Mar 17, 1980
• Grant date: May 4, 1982
• Expiry date: Mar 17, 2000

Classification

• Technology area (CPC G): Physics
• CPC primary: G02F1/1506
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

A display device and a method of using the display device characterized by a light trap which includes a member consisting of a material having an index of refraction greater than one and containing fluorescent particles and which light trap collects impinging ambient light by means of fluorescent scattering by the particles and subsequent reflection of the collected light on the boundary surfaces, a plurality of electrodes disposed adjacent the surface of the light trap at selected portions of the surface and a fluid being provided adjacent each of the electrodes so that an application of voltage to selected electrodes causes a precipitate to be formed from the fluid and collected adjacent the selected electrode to create an optical indication and the application of a counter voltage at the selected location causes an erasing of the indication by eliminating the precipitate and placing it back into the fluid. The precipitate may be separated from the fluid by an electrochemical process which may be either a metallic material or an organic electrochromic. The fluid may also be a suspension of particles which particles will be transported to a given location by the application of an…