Patent ID: 6597488
Filing Date: 2003-07-22
Classification: G02F

Abstract:
A display device being operated in a reflective mode (L) or in a transmissive mode (R) and having pixel elements (101-104) for modulating light, said pixel elements comprising:a stack of layers including a switchable layer (3) of an optically switchable material which switches the pixel elements (101-104) from a first state to a second state, the second state being different from the first state, the first state and the second state being one of the following states: a reflective state, a transmissive state or an absorbing state; and means for modulating light in the reflective mode (L) by switching from a reflective state to a non-reflective state, and for modulating light in the transmissive (R) mode by switching from a transmissive state to a non-transmissive state, the non-reflective state being the transmissive state or the absorbing state and the non-transmissive state being the reflective state or the absorbing state, the means for modulating light comprising electric switching means (22) for bringing said switchable layer (3) into the transmissive state by applying a surface charge density of substantially âˆ’Q to the switchable layer (3), into the reflective state by applying a surface charge density of substantially +Q to the switchable layer, and into the absorbing state by applying a surface charge density between +0.15 Q and +0.85 Q, respectively, to the switchable layer.