Display unit with touch detection function and electronic unit

Abstract

A display unit with touch detection function includes a plurality of pixel signal lines each transmitting a pixel signal for display; a pixel signal line drive section applying the pixel signal to each of the pixel signal lines; display elements each performing display based on the pixel signal; touch detection electrodes each outputting a detection signal based on a change in capacitance occurring due to an external proximity object; and a touch detection section detecting, in a touch detection period, a touch event based on the detection signal, the touch detection period being different from a display period for the display elements to perform display operation. The pixel signal line drive section maintains a voltage of each of the pixel signal lines at a certain level during the touch detection period.

Description

BACKGROUND[0001]The present disclosure relates to a display unit having touch detection function, and particularly relates to a display unit with touch detection function of detecting a touch event based on a change in capacitance due to an external proximity object, and an electronic unit having such the display unit with a touch detection function.[0002]Recently, a display unit has been notified, where a touch detection device, a so-called touch panel, is mounted on a display device such as liquid crystal display device, or the touch panel is integrated with the display device, and various button images or the like are displayed on the display device instead of common mechanical buttons, enabling information input. Such a display unit having the touch panel needs no input device such as a keyboard, a mouse, and a keypad and therefore tends to be expansively used not only for computers but also for handheld information terminals such as a mobile phone.[0003]A type of the touch dete...

AI Technical Summary

Benefits of technology

[0119]As described above, in the embodiment, the voltage of the pixel signal line SGL is prevented from being changed in the touch detection period, which makes it possible to suppress the change in the touch detection signal caused by the changes in the pixel signals, and thus influence of display operation on touch detection may be suppressed.

[0120]In the embodiment, a read switch is provided and turned on immediately before the touch detection period, which makes it possible to set the voltage of the touch detection signal Vdet to 0 V regardless of display content, and thus influence of display operation on touch detection may be suppressed.

[0121]While the source driver 13 applies the pixel signals Vpix to the pixel signal lines SGL via the selection switch section 14 in the embodiment, this is not limitative. Instead, for example, the source driver 13 may directly apply the pixel signals Vpix to the pixel signal lines SGL after generating the signals. In other words, while each pixel signal line SGL is made to be in a floating state to maintain the voltage of the pixel signal line SGL during the touch detection period in the embodiment, this is not limitative. Instead, for example, a voltage may be directly applied to each pixel signal line SGL to maintain the voltage of the pixel signal line SGL during the touch detection period.

[0122]Next, a display unit with a touch detection function 7 according to a second embodiment of the disclosure is described. In the embodiment, a predetermined voltage is applied to each pixel signal line SGL during a touch detection period Pt. It is to be noted that substantially the same components as those of the display unit with a touch detection function 1 according to the above-described first embodiment are designated by the same numerals, and description of them is appropriately omitted.

[0123]The display unit with a touch detection function 7 includes a source driver 13A and a detection timing control section 46A as illustrated in FIG. 4.

[0124]The source driver 13A generates a pixel signal Vsig including a predetermined voltage Vp (described later), and generates a switch control signal Vsel necessary for demultiplexing pixel signals Vpix multiplexed into the pixel signal Vsig and separating the predetermined voltage Vp, and supplies the switch control signal Vsel together with the pixel signal Vsig to a selection switch section 14. The predetermined voltage Vp is applied to all pixel signal lines SGL in all touch detection periods Pt and all periods before and after the respective touch detection periods.

Problems solved by technology

This may cause degradation in S / N ratio of the touch detection signal, leading to degradation in accuracy of touch position or the like.

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