摘要 |
<p>The invention relates to a light filter for use in front of a camera lens or a light projector. The light filter comprises two transparent plates (15, 17, 19) which are movable relative to one another and define between them a chamber (7, 9, 11) filled with a coloured fluid. By varying the separation between the plates, the effective density of the filter can be varied between zero and full saturation. If three filters of different primary colours are arranged in line, the hue and saturation of light given off by a projector (1) can be varied at will.</p> |