Method and apparatus for real-time on-off contrast ratio optimization in liquid crystal displays

A method for providing optimal on-off contrast ratio in a liquid crystal display panel having liquid crystal elements having optical transmission properties dependent upon applied voltage and temperature;

• said method comprising:
• a) applying driving voltage for said liquid crystal display panel voltage,
• b) dividing said voltage according to a voltage divider, an element of said voltage divider comprising a temperature sensing element formed in a pixel element of said liquid crystal display panel responsive to applied voltage and temperature, and outputting a sampled voltage representing a current sensed temperature;
• c) continously differentiating said sampled output voltage and detecting a peak voltage corresponding to a maximum rate of change of said voltage output from said temperature sensing element;
• d) measuring a difference between said peak voltage with a predetermined reference voltage, and outputting a signal representing said difference;
• and
• e) applying heat to said liquid crystal display in accordance with said measured temperature difference.