Abstract: A multicolor display device having seven illuminated optically stable states includes three triads of associated electro-optical components. In each triad, a light sensor is electrically coupled with a display light emitting diode and auxiliary light emitting diode. An optical feedback is established in each triad between the auxiliary light emitting diode and the light sensor tending to maintain its associated display light emitting diode either in the illuminated or extinguished condition. Light signals of respectively different colors emitted by three display light emitting diodes are blended to obtain a composite light signal of a color in accordance with the conditions of respective display light emitting diodes.

Abstract: A timepiece with variable color digital display indicates time in digital format and in a color variable in accordance with the output of a transducer. In the preferred embodiment, the color of the timepiece display is controlled, either in a plurality of steps or substantially continuously, in accordance with the functioning of a heart beating within the body of a timepiece user.

Abstract: A variable color display device comprising a plurality of display areas arranged in a pattern. Each display area includes a plurality of light emitting areas for emitting light signals of respectively different colors. Each light emitting area has a plurality of branches projecting thereof and interleaved with like branches of the other light emitting areas. The light signals of different colors emitted therefrom are substantially superimposed upon one another to mix the colors without the need for an optical coupling element.