Display device with touch detection function

Patent metadata

Field	Value
Publication number	US-2019102030-A1
Application number	US-201816139963-A
Country	US
Kind code	A1
Filing date	Sep 24, 2018
Priority date	Sep 29, 2017
Publication date	Apr 4, 2019
Grant date	—

Abstract

A display device with a touch detection function includes a touch detection electrode, first and second electrodes, a touch detection controller, and a force detection controller. The force detection controller performs interpolation processing on reference values to calculate an interpolation value when a reference force is applied to a position in an input surface at which a force has been applied by an object and calculates a force detection value based on a ratio of a detection value detected based on capacitance between first and second electrodes to the interpolation value. The position at which the force is applied is specified based on a position detected by the touch detection controller as a position of contact with the input surface by the object. The reference values are detected based on the capacitance between the first and second electrodes when the reference force is applied to reference positions.

First claim

What is claimed is:

1 . A display device with a touch detection function, the display device comprising:
a first substrate having an input surface; a touch detection electrode provided to the first substrate and facing the input surface; a first electrode provided to a second substrate and facing the touch detection electrode; a second electrode facing the first electrode with a dielectric layer interposed between the first electrode and the second electrode; a touch detection controller configured to detect a position at which a detection target object is in contact with or in proximity to the input surface based on capacitance between the first electrode and the touch detection electrode; a force detection controller configured to detect a force applied to the input surface by the detection target object based on capacitance between the first electrode and the second electrode and calculate a force detection value indicating the force; and storage configured to store therein a plurality of reference values detected by the force detection controller, wherein the force detection controller configured to
perform interpolation processing on the reference values to calculate an interpolation value when a reference force is applied to a position at which the force has been applied, and
calculate the force detection value based on a ratio of a detection value detected based on the capacitance between the first electrode and the second electrode relative to the interpolation value,
wherein the position at which the force is applied is specified based on a position detected by the touch detection controller as the position of contact with the input surface by the detection target object, and wherein the reference values are detected based on the capacitance between the first electrode and the second electrode when the reference force is applied to a plurality of reference positions.

2 . The display device with a touch detection function according to claim 1 ,
wherein the display device comprises a plurality of the second electrodes, wherein the storage stores therein a plurality of reference values of a first group for one second electrode that are detected based on capacitance between the first electrode and the one second electrode when the reference force is applied to the reference positions, wherein the force detection controller
performs the interpolation processing on the reference values of the first group to calculate a first interpolation value when the reference force is applied to the position at which the force has been applied,
calculates a first ratio of a first detection value detected based on capacitance between the first electrode and the one second electrode relative to the first interpolation value,
detects a plurality of reference values of a second group for another second electrode based on capacitance between the first electrode and the other second electrode when the reference force is applied to the reference positions,
performs the interpolation processing on the reference values of the second group to calculate a second interpolation value when the reference force is applied to the position at which the force has been applied,
calculates a second ratio of a second detection value detected based on capacitance between the first electrode and the other second electrode relative to the second interpolation value,
calculates a weighted average or an average of the first ratio and the second ratio, and
calculates the force detection value based on the weighted average or the average.

3 . The display device with a touch detection function according to claim 1 ,
wherein the display device comprises a plurality of the second electrodes, wherein the storage stores therein a plurality of reference values of a first group for one second electrode that are detected based on capacitance between the first electrode and the one second electrode when the reference force is applied to the reference positions, and wherein the force detection controller
performs the interpolation processing on the reference values of the first group to calculate a first interpolation value when the reference force is applied to the position at which the force has been applied,
detects a plurality of reference values of a second group for another second electrode based on capacitance between the first electrode and the other second electrode when the reference force is applied to the reference positions,
performs the interpolation processing on the reference values of the second group to calculate a second interpolation value when the reference force is applied to the position at which the force has been applied,
calculates a first average of the first interpolation value and the second interpolation value,
calculates a second average of a first detection value detected based on the capacitance between the first electrode and the one second electrode and a second detection value detected based on the capacitance between the first electrode and the other second electrode, and
calculates the force detection value based on a ratio of the first average relative to the second average.

4 . The display device with a touch detection function according to claim 1 ,
wherein the force detection controller detects the force applied to the input surface by the detection target object in a period during which the touch detection controller detects the position at which the detection target object is in contact with or in proximity to the input surface.

5 . The display device with a touch detection function according to claim 1 ,
wherein the dielectric layer includes an air gap.

6 . The display device with a touch detection function according to claim 1 ,
wherein the dielectric layer includes a multilayered body included in a configuration of a backlight illuminating the input surface.

7 . The display device with a touch detection function according to claim 6 ,
wherein the second electrode is provided on a surface of the multilayered body opposite to a surface on a side of the input surface.

8 . The display device with a touch detection function according to claim 6 ,
wherein the second electrode is provided on a surface of the multilayered body on a side of the input surface.

9 . The display device with a touch detection function according to claim 6 ,
wherein the second electrode is provided in an inner layer of the multilayered body.

10 . The display device with a touch detection function according to claim 1 ,
wherein the interpolation processing is polynomial interpolation or linear interpolation.

11 . A display device with a touch detection function, the display device comprising:
a first substrate having an input surface; a first electrode provided to the first substrate; a second electrode facing the first electrode with a dielectric layer interposed between the first electrode and the second electrode; a touch detection controller configured to detect a position at which a detection target object is in contact with or in proximity to the input surface based on capacitance of the first electrode; and a force detection controller configured to detect a force applied to the input surface by the detection target object based on capacitance between the first electrode and the second electrode and calculate a force detection value indicating the force; and storage configured to store therein a plurality of reference values detected by the force detection controller, wherein the force detection controller configured to
perform interpolation processing on the reference values to calculate an interpolation value when a reference force

Assignees

• Japan Display Inc

Inventors

• Kakinoki Yuto
• Takada Naoki

Classifications

• G06F3/0443

  using a single layer of sensing electrodes · CPC title

• G06F3/04182

  Filtering of noise external to the device and not generated by digitiser components · CPC title

• G06F3/0418

  for error correction or compensation, e.g. based on parallax, calibration or alignment · CPC title

• G06F3/0416

  Control or interface arrangements specially adapted for digitisers · CPC title

• G06F2203/04105

  Pressure sensors for measuring the pressure or force exerted on the touch surface without providing the touch position · CPC title