A PDP Sub-field Coding Algorithm for the Reduction of Errors due to Line Load Variation

The displayed luminance level of a PDF is different from the intended target level due to the variation of the line load (the number of on-cells in a scan line). The conventional luminance generation algorithm does not take this difference into consideration and, therefore, may deteriorate the display quality. In this paper, an RC circuit model is proposed to analyze the relationship between the displayed luminance level and the line load. The model indicates that the luminance level decreases as the line load increases. The luminance variations depending on the line load are formulated as the third order regression equations for red, green and blue colors, respectively. Based on the equations, this paper proposes a new luminance generation algorithm to reduce luminance errors caused by the variation of the line load. The proposed algorithm performs the conventional algorithm three times with new weight vectors (i.e. the expected luminance levels of sub-fields) adjusted based on the detected error of the previous run of the conventional algorithm. Simulations and experiments with a 50-inch PDF show significant error reduction results including 83.4% improvement of the maximum error with 164,480 test patterns.