Touch detection device, method, and display that flatten noise on block regions formed by common electrodes

A touch detection method of a display device, the display device including a plurality of common electrodes arranged in a matrix and used for image display and touch detection, the touch detection method comprising:

• acquiring a plurality of first detection values that are based on capacitance of each of the plurality of common electrodes;
• calculating second detection values in a plurality of block regions, each of the plurality of block regions containing two or more common electrodes out of the plurality of common electrodes, the second detection values being calculated based on the plurality of first detection values;
• and
• detecting a touch by a conductor on a display screen of the display device based on the second detection values, wherein
• the plurality of block regions includes at least a first block region and a second block region,
• the first block region includes, out of the plurality of common electrodes, at least a first common electrode and a second common electrode adjacent to the first common,
• the second block region includes, out of the plurality of common electrodes, at least the second common electrode and a third common electrode, the third common electrode being adjacent to the second common electrode and different from the first common electrode,
• in the calculating, for each block region of the plurality of block regions in the display screen, a second detection value is calculated based on a corresponding first detection value of each of the two or more common electrodes included in the block region,
• when the second detection value of the first block region is equal to or greater than a touch detection threshold value and is equal to or greater than a grouping threshold value for determining whether or not to reduce a size of the first block region and specify a position of the touch using smaller block regions, the touch detection method further comprises:
• generating a plurality of second block regions, each of the plurality of second block regions having a size smaller than the first block region;
• and
• calculating third detection values of the plurality of second block regions, the plurality of second block regions including at least the two or more common electrodes included in the first block region,
• the touch detection threshold value is for detecting the touch, and
• the grouping threshold value is for, after detecting the touch, specifying the position of the touch using the smaller block regions.

A touch detection device of a display device, the display device including a plurality of common electrodes arranged in a matrix and used for image display and touch detection, the touch detection device comprising:

• a touch detection circuit which, in operation;
• acquires a plurality of first detection values that are based on capacitance of each of the plurality of common electrodes;
• calculates second detection values in a plurality of block regions, each of the plurality of block regions containing two or more common electrodes out of the plurality of common electrodes, the second detection values being calculated based on the plurality of first detection values;
• and
• detects a touch by a conductor on a display screen of the display device based on the second detection values, wherein
• the plurality of block regions includes at least a first block region and a second block region,
• the first block region includes, out of the plurality of common electrodes, at least a first common electrode and a second common electrode, the second common electrode being adjacent to the first common electrode,
• the second block region includes, out of the plurality of common electrodes, at least the second common electrode and a third common electrode, the third common electrode being adjacent to the second common electrode and different from the first common electrode,
• the touch detection circuit calculates, for each block region of the plurality of block regions in the display screen, a second detection value based on a corresponding first detection value of each of the two or more common electrodes included in the block region, and
• the touch detection circuit acquires difference values with respect to reference capacitances of the plurality of common electrodes as the first detection values, converts respective first detection values of the two or more common electrodes included in each block region of the plurality of block regions that are equal to zero or below to one, and then multiplies the respective first detection values of each block region after conversion so as to calculate the second detection values of the plurality of block regions.