Touch detection device and display device with touch detection function

A display device with a touch detection function that detects a touch operation in a detection region on a display surface side of the display device based on variation in capacitance, the display device with a touch detection function comprising:

• a plurality of drive electrodes arranged in parallel with each other in the detection region;
• a plurality of first touch detection electrodes arranged in parallel with each other in the detection region, each of the first touch detection electrodes being arranged at a portion not in contact with the drive electrodes and where each of the first touch detection electrodes forms capacitance with one of the drive electrodes to which a drive signal is input;
• and
• a display panel with pixels, wherein
• the drive electrodes include a drive electrode and first drive electrodes, the drive electrode including a plurality of subdivided electrodes an arrangement pitch of which is finer than an arrangement pitch of the drive electrodes, each of the first drive electrodes not having a plurality of subdivided electrodes,
• a width of the drive electrode including the subdivided electrodes in a first direction in which the drive electrodes are arranged is the same as a width of one of the first drive electrodes in the first direction,
• a length of the drive electrode including the subdivided electrodes in a second direction in which the drive electrodes run and a length of each of the subdivided electrodes in the second direction are the same as a length of the one of the first drive electrodes in the second direction,
• the drive electrode including the subdivided electrodes is provided such that switching is enabled between a first mode in which the drive signal is input to all of the subdivided electrodes at a same time and a second mode in which the drive signal is sequentially input to each of the subdivided electrodes of the drive electrode,
• video signals are input to the pixels within a display output period, the touch detection device detects the touch operation within a first sensing period in the first mode and within a second sensing period in the second mode,
• a first frame period includes the display output period and the first sensing period,
• a second frame period includes the display output period and the second sensing period, the second frame period immediately following the first frame period, and
• the first frame period and the second frame period are alternately provided on a frame-period-by-frame-period basis.