colour filter based on vätskekristaller intended for electronic photography and display

摘要

A liquid crystal switchable colour filter is described. For electronic photography it can be configured to switch between the colours cyan, magenta, and yellow, to get good properties for colour separation. It could alternatively be configured to switch between the colours red, green, blue and colourless for display purposes, e.g. in field sequential colour displays. The filter consists of a stack of plates, the first and seventh plate being polarizers, the second, fourth, and sixth plate being retarder plates (synonym "phase plates" or "birefringent plates") or groups of retarder plates, the third and fifth being liquid crystal panels (cells), that could be a ferroelectric smectic-C cell in the bookshelf geometry, and the eighth plate being a passive colour filter. The optical properties of this plate combination can be optimised by varying the thicknesses of the components and the angles between the optical directions along the plates.