Patent ID: 7986316
Filing Date: 2011-07-26
Classification: G09G

Abstract:
1. Method for power level control in a display device having a plurality of luminous elements corresponding to the pixels of an input picture, wherein the time duration of a video frame is divided into a plurality of subfields during which each luminous element can be activated for light emission in small pulses, called hereinafter sustain pulses, corresponding to a subfield code word representative of the video level of the corresponding pixel, wherein a set of power level modes is provided for subfield coding wherein to each power level mode a characteristic subfield organization belongs, the subfield organizations being variable in respect to the number of sustain pulses during a frame, comprising a step for determining an average power value which is characteristic for the picture to be displayed, and transforming the average picture power value into a first number of sustain pulses a step for measuring the frame frequency of the input picture, transforming the frame frequency of the input picture into a maximum allowed number of sustain pulses and a sustain gain, and multiplying the first number of sustain pulses by said sustain gain for delivering a second number of sustain pulses and a step for selecting a minimum number of sustain pulses between said second number of sustain pulses and said maximum allowed number of sustain pulses for transforming minimum pulses into a power level mode.