Electrophoretic image display device

• Main Authors: DALISA, A.L, SEYMOUR, R.J
• Format: Patent
• Language: English; French; German
• Published: 11.02.1981
• Subjects: CINEMATOGRAPHY; DEVICES OR ARRANGEMENTS, THE OPTICAL OPERATION OF WHICH ISMODIFIED BY CHANGING THE OPTICAL PROPERTIES OF THE MEDIUM OF THEDEVICES OR ARRANGEMENTS FOR THE CONTROL OF THE INTENSITY,COLOUR, PHASE, POLARISATION OR DIRECTION OF LIGHT, e.g.SWITCHING, GATING, MODULATING OR DEMODULATING; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; FREQUENCY-CHANGING; HOLOGRAPHY; MAGNETOGRAPHY; NON-LINEAR OPTICS; OPTICAL ANALOGUE/DIGITAL CONVERTERS; OPTICAL ELEMENTS, SYSTEMS, OR APPARATUS; OPTICAL LOGIC ELEMENTS; OPTICS; PHOTOGRAPHY; PHYSICS; TECHNIQUES OR PROCEDURES FOR THE OPERATION THEREOF

A light transmissive electrophoretic image display device is provided, which device comprises a light transmissive first panel element (34) and a light transmissive second panel element (24). A light transmissive first electrode (44) and a light transmissive second electrode (70) are disposed on the opposing surfaces of the first and second panel element (34, 24) respectively. A light transmissive fluid 68 containing colloidal particles (76) having a charge of one polarity is held between the plate elements (34, 24). The refractive indices of the fluid (68) and the particles (76) differ from each other and the second panel element (24) has a refractive index greater than the refractive index of the fluid (68). Illumination (26) received in the second panel element (24) is totally internally reflected at the regions free of particles (76) and illumination (26) is coupled into the device at the regions (80) where particles (76) are present. The device can also be used in a reflective mode in order to provide projection of the image formed by the device to a viewing screen.