Abstract: The design of a liquid crystal(LC) device was presented, which could be used to measure and regulate the polarization state of the incident light by only changing the voltage amplitude of the driving signal applied over the patterned electrodes, and simulate the direction orientation distribution in the LC layer of the device. As known, the tilt angle of the LC molecular can be controlled easily. However, it always was ignored that the twist angle could also be electrically controlled. So, the LC material can be used as a variable and rotatable phase retarder, and then the polarization state was regulated after measuring the polarized incident light through the same testing architecture. The direction orientation distribution of the LC layer with the cross-shape electrodes was simulated firstly. Results show that the twist angle can be electrically controlled, and it is achievable to regulate the polarized state of incident light to any desired polarization state.