Full color reflective display with multichromatic sub pixels

Abstract

A full color, reflective display having superior saturation and brightness is achieved with a novel display element comprising multichromatic elements. In one embodiment a capsule includes more than three species of particles which differ visually. One embodiment of the invention employs three sub-pixels, each sub-pixel comprising capsules including three species of particles which differ visually. Another embodiment of the invention employs color filters to provide different visual states to the user. The display element provides a visual display in response to the application of an electrical signal to at least one of the capsules.

1 . A color reflective electronic display comprising at least two microcells each containing at least two particles and not having any suspending fluid, the microcells being disposed adjacent a color filter. 
     
     
         2 . A display according to  claim 1  in combination with at least one electrode. 
     
     
         3 . A display according to  claim 2  having a plurality of electrodes arranged to drive the display using a passive matrix addressing scheme. 
     
     
         4 . A display according to  claim 2  further comprising at least one thin film transistor arranged to control the potential of the at least one electrode. 
     
     
         5 . A display according to  claim 4  further comprising a flexible substrate on which the thin film transistor is disposed. 
     
     
         6 . A display according to  claim 1  wherein the at least two microcells are formed by photolithography. 
     
     
         7 . A display according to  claim 1  wherein the at least two microcells are formed by embossing a plastic substrate. 
     
     
         8 . A color reflective electronic display comprising at least one pixel having a plurality of sub-pixels, wherein at least one of the sub-pixels is capable of displaying three colors. 
     
     
         9 . A display according to  claim 8  wherein said at least one sub-pixel comprises an electrophoretic medium comprising first and second types of electrically charged particles bearing charges of opposite polarity and differing in at least one optical characteristic. 
     
     
         10 . A display according to  claim 9  wherein said at least one sub-pixel has a viewing surface and is capable of being driven to a first optical state, in which the first type of particles are disposed adjacent the viewing surface and the second type of particles are disposed spaced from the viewing surface, a second optical state, in which the second type of particles are disposed adjacent the viewing surface and the first type of particles are disposed spaced from the viewing surface, and a third optical state in which both the first and second types of particles are disposed spaced from the viewing surface. 
     
     
         11 . A display according to  claim 10  wherein the first and second types of particles are disposed in a colored fluid, and the third optical state displays the color of the colored fluid. 
     
     
         12 . A display according to  claim 10  wherein said at least one sub-pixel further comprises a third type of particles, the third type of particles being substantially uncharged and differing from the first and second types of particles in at least one optical characteristic, and wherein the third optical state displays the optical characteristic of the third type of particles. 
     
     
         13 . A display according to  claim 10  wherein said at least one sub-pixel further comprises a colored member disposed on the opposed side of the sub-pixel from the viewing surface, and wherein the third optical state displays the optical characteristic of the colored member.