Display device comprising a light valve unit in conjunction with the fluorescent plate

US4235527A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• Waldemar Greubel · Munich, DE
• Hans Kruger · Birkenfeld, DE

Key dates

• Filing date: Feb 23, 1979
• Grant date: Nov 25, 1980
• Expiry date: Feb 23, 1999

Classification

• Technology area (CPC G): Physics
• CPC primary: G02F1/133617
• WIPO field: Optics
• WIPO sector: Instruments

Abstract

An improved display device having a light valve unit or display and a fluorescent plate characterized by a frame member for holding the light valve unit and fluorescent plate with the exit windows of the fluorescent plate being aligned with the switchable zones of the light valve unit. Preferably, the frame member will pass light which will excite the fluorescent particles of the fluorescent plate but will not allow passage of the fluorescent light so that a high contrast of the display can be obtained. The frame, which is preferably molded of synthetic plastic, can contain fluorescent particles, which emit light at a frequency range that does not impair the optical contrast of the display and which can be utilized to charge a battery for an auxiliary illumination device.