Display device and electronic unit
First Claim
1. A display device comprising:
- a plurality of display pixel electrodes;
a common electrode facing the display pixel electrodes;
a display function layer having an image display function;
a display control circuit performing image display control by applying a pixel voltage to each of the display pixel electrodes and applying a common drive voltage periodically to the common electrode, the common drive voltage inverting in synchronization with a drive cycle of the image display control;
a touch detection electrode having a capacitance with the common electrode; and
a touch detection circuit performing a detection operation of detecting an external proximity object, based on a detection signal obtained from the touch detection electrode,wherein the touch detection circuit performs the detection operation in a period of time following an inversion timing of the common drive voltage and only during a time preceding an image-signal writing operation, based on both a first detection signal obtained during a time after another image-signal writing operation and before the inversion timing, and a second detection signal obtained after the inversion timing and before an image-signal writing operation;
a first noise-eliminated detection signal is obtained by subtracting a predetermined first value from the first detection signal, a second noise-eliminated detection signal is obtained by subtracting a predetermined second value from the second detection signal; and
the touch detection circuit performing the detection operation to detect the external proximity object by comparing the first noise-eliminated detection signal and a predetermined threshold value, and further wherein the first noise-eliminated detection signal is a pre-inversion noise eliminated detection signal and the second noise-eliminated detection signal is a post-inversion noise eliminated detection signal and the first and second predetermined values are different from each other.
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Accused Products
Abstract
The display device with high detection accuracy includes: display pixel electrodes; a common electrode; a display function layer; a display control circuit performing image display control by applying a pixel voltage to each of the display pixel electrodes and applying a common drive voltage to the common electrode, the common drive voltage inverting in synchronization with a drive cycle of the image display control; a touch detection electrode cooperating with the common electrode to form a capacitor; and a touch detection circuit detecting an external proximity object, based on a detection signal obtained from the touch detection electrode in response to the common drive voltage applied to the common electrode. The touch detection circuit performs the detection operation in a inversion period following an inversion timing of the common drive voltage, based on both first and second detection signals obtained before and after the inversion timing, respectively.
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Citations
14 Claims
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1. A display device comprising:
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a plurality of display pixel electrodes; a common electrode facing the display pixel electrodes; a display function layer having an image display function; a display control circuit performing image display control by applying a pixel voltage to each of the display pixel electrodes and applying a common drive voltage periodically to the common electrode, the common drive voltage inverting in synchronization with a drive cycle of the image display control; a touch detection electrode having a capacitance with the common electrode; and a touch detection circuit performing a detection operation of detecting an external proximity object, based on a detection signal obtained from the touch detection electrode, wherein the touch detection circuit performs the detection operation in a period of time following an inversion timing of the common drive voltage and only during a time preceding an image-signal writing operation, based on both a first detection signal obtained during a time after another image-signal writing operation and before the inversion timing, and a second detection signal obtained after the inversion timing and before an image-signal writing operation; a first noise-eliminated detection signal is obtained by subtracting a predetermined first value from the first detection signal, a second noise-eliminated detection signal is obtained by subtracting a predetermined second value from the second detection signal; and the touch detection circuit performing the detection operation to detect the external proximity object by comparing the first noise-eliminated detection signal and a predetermined threshold value, and further wherein the first noise-eliminated detection signal is a pre-inversion noise eliminated detection signal and the second noise-eliminated detection signal is a post-inversion noise eliminated detection signal and the first and second predetermined values are different from each other. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13)
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14. An electronic unit comprising a display device with a touch sensor, the display device including:
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a plurality of display pixel electrodes; a common electrode facing the display pixel electrodes; a display function layer having an image display function; a display control circuit performing image display control by applying a pixel voltage to each of the display pixel electrodes and applying a common drive voltage to the common electrode, the common drive voltage periodically inverting in synchronization with a drive cycle of the image display control; a touch detection electrode having a capacitance with the common electrode; and a touch detection circuit performing a detection operation of detecting an external proximity object, based on a detection signal obtained from the touch detection electrode, wherein the touch detection circuit performs the detection operation in a period of time following an inversion timing of the common drive voltage and only during a time preceding an image-signal writing operation, based on both a first detection signal obtained before the inversion timing and a second detection signal obtained after the inversion timing; a first noise-eliminated detection signal is obtained by subtracting a predetermined first value from the first detection signal, a second noise-eliminated detection signal is obtained by subtracting a predetermined second value from the second detection signal; and the touch detection circuit performing the detection operation to detect the external proximity object by comparing the first noise-eliminated detection signal, the second noise-eliminated detection signal and a predetermined threshold value, and further wherein the first noise-eliminated detection signal is a pre-inversion noise eliminated detection signal and the second noise-eliminated detection signal is a post-inversion noise eliminated detection signal and the first and second predetermined values are different from each other.
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Specification