Liquid crystal writing device

Abstract

Embodiments are disclosed for selectively and partially erasing images from a liquid crystal writing device. A liquid crystal writing device according to some embodiments includes a transparent top layer, a liquid crystal layer including a plurality of liquid crystal cells beneath the transparent top layer, a matrix of electrodes, and a control circuitry. The liquid crystal layer displays an image by switching cells to a reflective state. The writing device detects a mechanical pressure applied on a pressed area, the mechanical pressure indicating a command to erase at least a portion of the image from the pressed area. The control circuitry instructs one or more electrodes from the matrix to apply an erase voltage signal to a portion of the liquid crystal cells that correspond to the pressed area, wherein the erase voltage signal switches the portion of the liquid crystal cells to the scattering state.

What is claimed is: 
     
         1 . An electronic writing device, comprising:
 a transparent top layer;   a liquid crystal layer including a plurality of liquid crystal cells beneath the transparent top layer, the liquid crystal layer configured to display an image by switching one or more of the liquid crystal cells from a scattering state to a reflective state;   a matrix of electrodes configured to supply voltage signals to the liquid crystal cells; and   a control circuitry configured to receive an erase command, the erase command indicating that a touched area of the transparent top layer is touched and instructing to erase at least a portion of the image from the touched area;   wherein the control circuitry is further configured to instruct one or more electrodes from the matrix to apply an erase voltage signal to a portion of the liquid crystal cells that correspond to the touched area, wherein the erase voltage signal switches the portion of the liquid crystal cells to the scattering state.