Patent ID: 6594929
Filing Date: 2003-07-22
Classification: F21S,F21V,G09F

Abstract:
A display device which includes a plurality of superimposed light-transmitting walls defining at least one intervening chamber containing two immiscible fluids having different densities and which are visually distinguished by the fluid with the greater density being coloured and the less dense fluid being substantially colourless, in which said walls are mounted for rotation about an axis which is substantially normal to their plane, and said chamber includes means for collecting fluid at one region of said chamber, carrying it to another region of said chamber and releasing the fluid as the walls rotate, in which said chamber is substantially filled with the coloured fluid while leaving a gap adjacent to the top of said chamber, which gap contains the less dense fluid, and in which said means for collecting fluid is arranged to collect the less dense fluid from the top of said chamber and release it in a bottom region of said chamber such that discrete, colourless volumes of the less dense fluid move upwardly through the coloured fluid.