Patent ID: 8456383
Filing Date: 2013-06-04
Classification: G09G

Abstract:
1. A method for controlling a liquid crystal segment display, wherein alternating control signals are applied to said segment display so as to control opacity of the segment display, the method comprising determining a value of a supply voltage of a power source by comparison with a reference value, adapting using a logical circuit, the shape of at least certain of said signals according to the determined value of the supply voltage so as to compensate at least partially for variation in the supply voltage to provide a more uniform opacity of the segment display, the adapting comprising when the determined value of the supply voltage exceeds a determined threshold, adding further pulses to an alternating control signal applied to a front electrode and to an alternating control signal applied to a back electrode of inactive segments of the segment display so as to reduce the cycle ratio of a resulting voltage, and, when the determined value of the supply voltage goes below a second determined threshold, adding further pulses to an alternating control signal applied to a front electrode and to an alternating control signal applied to a back electrode of active segments of the segment display so as to increase the cycle ratio of the resulting voltage.