Patent ID: 8063897

Claim:
A display device configured to convert input tonal data into a plurality of tonal data, and configured to display said plurality of tonal data during a period while an input tonal data of a one frame is displayed, and having a signal processing circuit configured to process at double speed, through time division of the one frame into a first subframe and a second subframe, said signal processing circuit comprising: a memory configured to store input tonal data of a frame period, said stored input tonal data being read during the first and the second subframe periods; a calculation circuit configured to conduct a calculation, using parameters and subframe tonal data read from said memory, and configured to output a calculated result; a register configured to store a plurality of parameters generated by a parameter generator circuit, and configured to output the parameters; a selector circuit configured to select a parameter among a plurality of parameters output from the register, and configured to output the selected parameter to said calculation circuit; and a sync signal generator circuit configured to be responsive to an input sync signal, configured to output a memory control signal to said memory, configured to output a double-speed sync signal to said calculation circuit, and configured to output a subframe distinguishing signal to said selector circuit; wherein said plurality of tonal data include high tonal data having a higher tone than said input tonal data, and include low tonal data having a lower tone than said input tonal data; wherein in a graph representing output tonal data along a vertical axis and the input tonal data along a horizontal axis, characteristics of said high tonal data are such that the output tonal data has a plurality of bending points and is higher than the input tonal data, and characteristics of said low tonal data are such that the output tonal data has another plurality of bending points and is lower than the input tonal data; wherein a calculation by said calculation circuit uses sets of formulas to make a luminance of output tonal data high during the first subframe period and low during the second subframe period; and wherein each set of formulas represents a broken line shape including a plurality of bending points.