Display device, display device drive method, and computer program

A driving method for a display device, the display device having a display unit in which pixels which have light emitting elements that self-emit light according to an electric current amount and pixel circuits for controlling an electric current applied to the light emitting elements according to video signals, scanning lines which supply selection signals for selecting the pixels that are caused to emit light to the pixels in a predetermined scanning cycle, and data lines which supply the video signals to the pixels are arranged into a matrix pattern, the driving method comprising the steps of:

• inputting video signals having linear characteristic and calculating an average value of signal levels of the video signals in each of the pixels;
• storing the average values calculated at the average value calculating step;
• judging whether a still image is displayed on the display unit by dividing the display unit into a plurality of regions and judging whether a still image is displayed on each of the plurality regions based on a difference between the average value stored at the average value storing step and a last average value;
• storing a value for respective regions of the plurality of regions;
• when it is judged that a still image is displayed on a respective one of the plurality of regions, increasing the value by a first predetermined amount;
• when it is judged that a moving image is displayed on the respective one of the plurality of regions, decreasing the value by a second predetermined amount;
• when it is judged that a still image is displayed on the display unit as a result of the judgment at the still image judging step, calculating coefficients for reducing luminance of an image displayed on the display unit based on the value;
• and
• multiplying the video signals by the coefficients calculated at the coefficient calculating step,
• wherein when it is judged that the still image is displayed on at least one of the plurality of regions, it is judged that the still image is displayed on the entire screen, and wherein coefficients for reducing luminance for the respective one of the plurality of regions is decreased as the value is increased beyond a first threshold, and coefficients for reducing luminance for the entire screen are decreased as the value is increased beyond a second threshold which is higher than the first threshold.

A non-transitory computer readable storage medium that stores a program which causes a computer to execute control of a display device having a display unit in which pixels which have light emitting elements that self-emit light according to an electric current amount and pixel circuits for controlling an electric current applied to the light emitting elements according to video signals, scanning lines which supply selection signals for selecting the pixels that are caused to emit light to the pixels in a predetermined scanning cycle, and data lines which supply the video signals to the pixels are arranged into a matrix pattern, the computer program comprising the steps of:

• inputting video signals having linear characteristic and calculating an average value of signal levels of the video signals in each of the pixels;
• storing the average values calculated at the average value calculating step;
• judging whether a still image is displayed on the display unit by dividing the display unit into a plurality of regions and judging whether a still image is displayed on each of the plurality of regions based on a difference between the average value stored at the average value storing step and a last average value;
• storing a value for respective regions of the plurality of regions;
• when it is judged that a still image is displayed on a respective one of the plurality of regions, increasing the value by a first predetermined amount;
• when it is judged that a moving image is displayed on the respective one of the plurality of regions, decreasing the value by a second predetermined amount;
• when it is judged that a still image is displayed on the display unit as a result of the judgment at the still image judging step, calculating coefficients for reducing luminance of an image displayed on the display unit based on the value;
• and
• multiplying the video signals by the coefficients calculated at the coefficient calculating step,
• wherein when it is judged that the still image is displayed on at least one of the plurality of regions, it is judged that the still image is displayed on the entire screen, and wherein coefficients for reducing luminance for the respective one of the plurality of regions is decreased as the value is increased beyond a first threshold, and coefficients for reducing luminance for the entire screen are decreased as the value is increased beyond a second threshold which is higher than the first threshold.