Screen for a free and a restricted viewing mode

US10838133B2 · kind B2 · utility

Assignee

• siOPTICA GmbH · DE

Inventors

• André Heber · Weimar, DE
• Uwe Schroeter · Naschhausen, DE
• Juergen Schwarz · Apolda, DE
• Ambrose Peter Nari · Jena, DE
• Markus Klippstein · Jena, DE
• Stepan Alkhimenko · Jena, DE

Key dates

• Filing date: Jun 2, 2020
• Grant date: Nov 17, 2020
• Expiry date: Jun 2, 2040

Classification

• Technology area (CPC G): Physics
• CPC primary: G02B6/0035
• WIPO field: Electrical machinery, apparatus, energy
• WIPO sector: Electrical engineering

Abstract

A screen with a transmissive image generator with pixels which is operable in at least two operating modes, B1 for a free viewing mode and B2 for a restricted viewing mode, and with an illuminating apparatus comprising a backlight that has a planar extension and radiates light in a restricted angular range, a plate-shaped light guide arranged in front of the backlight and provided with outcoupling elements on one of the large surfaces and/or within its volume, the light guide being transparent to at least 70% of the light emitted by the backlight; and light sources arranged laterally at edges of the light guide. In mode B2, the backlight is switched on and the light sources are switched off, and in mode B1 at least the light sources are switched on. In interaction with the transmissive image generator the illuminating apparatus constitutes an advantageous screen permitting the operating modes.