Light switching device
First Claim
Patent Images
1. Display device (20) being operable in a reflective mode (L) or in a transmissive mode (R) and having pixel elements for modulating light, each of said pixel elements comprising:
- a stack of layers including a switchable layer (3) of an optically switchable material that switches the pixel elements 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 or scattering 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 or scattering state or the absorbing state, the means for modulating light comprising for each pixel element a first series connection of two complementary switches (31,32) between two voltage connections (35,36), the common point of said series connection being connected to a first connection (13) of the pixel element an intermediate voltage being provided to a second connection (11) of the pixel element, the complementary switches being controlled by storage means (33), the display device comprising further means(22, 23, 34) for controlling the storage means.
1 Assignment
0 Petitions
Accused Products
Abstract
In an active matrix display (20) comprising pixels based on switching mirror display elements (30) the driving circuit provides continous current in two directions (charge/discharge) and prevents device degradation
12 Citations
9 Claims
-
1. Display device (20) being operable in a reflective mode (L) or in a transmissive mode (R) and having pixel elements for modulating light, each of said pixel elements comprising:
-
a stack of layers including a switchable layer (3) of an optically switchable material that switches the pixel elements 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 or scattering 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 or scattering state or the absorbing state,the means for modulating light comprising for each pixel element a first series connection of two complementary switches (31,32) between two voltage connections (35,36), the common point of said series connection being connected to a first connection (13) of the pixel element an intermediate voltage being provided to a second connection (11) of the pixel element, the complementary switches being controlled by storage means (33), the display device comprising further means(22, 23, 34) for controlling the storage means. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9)
-
Specification