Patent ID: 8023079

Claim:
A liquid crystal display, comprising: a liquid crystal display panel including a first substrate and a second substrate; a liquid crystal layer disposed between the first substrate and the second substrate; a first polarizing plate positioned under the first substrate; a second polarizing plate positioned on the second substrate; and a plurality of reflective coding patterns disposed in a position selected from a group consisting of above the second polarizing plate, between the second polarizing plate and the second substrate, and integrated into the second polarizing plate; wherein the reflective coding patterns include a plurality of cholesteric liquid crystal molecules, and the cholesteric liquid crystal molecules are used to provide an encoded data for a light pen to detect the encoded data from the corresponding cholesteric liquid crystal molecules, wherein said reflective coding patterns are encoded by a coding system including one selected from a group consisting of a hexagonal dot-coding system, a 2-dimensional bar coding system, and a 3-dimensional bar coding system.