Patent ID: 8427501

Claim:
A method of calibration of a display device by iteration to optimize an electrical control voltage of the display device, the calibration method comprising: iteratively measuring an optical contrast of the display device and calculating an electrical control voltage value, wherein the measurement of the optical contrast and the calculation of the electrical control voltage value are carried out once during each iteration, wherein the optimization of the electrical control voltage is carried out starting from an initial value of the electrical control voltage and ending with a final value of the electrical control voltage, wherein the iterations include an initial calibration step carried out once and comprising calculating a new value (TDP new ) of the electrical control voltage starting from an initial standard value (CO initial ) of the optical contrast and a final standard value (CO final ) of the optical contrast, from a measured value (CO measured ) of the optical contrast, and from a final value (TDP final ) of the control voltage according to: TDP new =TDP final *( [CO measured −CO final ]/ [CO initial− CO final ]), wherein the iterations include at least one calibration refinement step, the calibration refinement step comprising calculating at least one of a subsequent value (TDP subsequent ) of the electrical control voltage starting from a preceding value (TDP preceding ) of the electrical control voltage, from the measured value of the optical contrast, and from a standard final value of the topical contrast and by using a constant (G) according to: TDP subsequent =TDP preceding +round ([ CO final −CO measured ]* G ), an approximation of the final value of the electrical control voltage due to the initial calibration step being higher than the approximation of the final value of the electrical control voltage due to the calibration refinement step.