Global Patent Index - EP 0857318 A1

EP 0857318 A1 19980812 - A LIGHT VALVE

Title (en)

A LIGHT VALVE

Title (de)

LICHTVENTIL

Title (fr)

MODULATEUR DE LUMIERE

Publication

EP 0857318 A1 19980812 (EN)

Application

EP 96937482 A 19961023

Priority

  • IE 9600067 W 19961023
  • IE 950825 A 19951023

Abstract (en)

[origin: WO9715861A1] A light valve (2) for framing a transparency on an overhead projector when the transparency is arranged in both portrait and landscape orientations comprises a liquid crystal display panel (3). Electrodes (30 and 31) are formed on a front side (27) and electrodes (32 and 33) are formed on a rear side (28) of the panel (3). The electrodes (30 to 33) define three rows (35a, 35b, 35c) of pixels (34) and a plurality of columns (36) of pixels (34). The light valve (2) may be operated with all the pixels (34) in the centre row (35b) operating in light transmitting mode and the pixels (34) in the side rows (35a, 35c) in light scattering mode for forming two side frames for partially framing the transparency (4) in portrait orientation. For framing the transparency in landscape orientation, a plurality of columns (36a) of pixels (34) on either side of the X-axis (25) are operated in light transmitting mode, and pixels (34) in columns (36b) adjacent the top and bottom of the light valve (2) are operated in light scattering mode for forming a top and bottom frame for the transparency in landscape mode.

IPC 1-7

G02F 1/1343; G03B 21/132

IPC 8 full level

G02F 1/1343 (2006.01); G03B 21/132 (2006.01)

CPC (source: EP)

G02F 1/134309 (2013.01); G03B 21/132 (2013.01)

Citation (search report)

See references of WO 9715861A1

Designated contracting state (EPC)

DE ES FR GB IE IT

DOCDB simple family (publication)

WO 9715861 A1 19970501; AU 7503796 A 19970515; EP 0857318 A1 19980812

DOCDB simple family (application)

IE 9600067 W 19961023; AU 7503796 A 19961023; EP 96937482 A 19961023