Patent ID: 6243069
Filing Date: 2001-06-05
Classification: G02F,G09G,H04N

Abstract:
A liquid crystal display device with a function of reading a picture comprising:a plurality of source lines for transferring a picture signal;a plurality of gate lines for transferring a scanning signal which are provided in a crossing direction with said source lines;a pixel electrode which is provided corresponding to each crossing section of the source lines and the gate lines;a first transistor which is connected to the source lines and the gate lines as well as each of the pixel electrodes;an opposite electrode which is provided opposite to the pixel electrode;a liquid crystal which is provided between the pixel electrode and the opposite electrode; anda photo detector for detecting a quantity of a reflected light from an original which is provided corresponding to each of the pixel electrodes;fiber comprising:a second transistor which is connected to said source lines and said gate lines as well as one end of the photo detector; andthe other end line which is connected to the other end of the photo detector;said liquid crystal display device with a function of reading a picture wherein:a threshold value of a gate voltage in said first transistor and a threshold value of a gate voltage in said second transistor are determined so that at least only the second transistor can be made an ON state.