Touch detection device and display device having touch sensor function

Patent metadata

Field	Value
Publication number	US-9274653-B2
Application number	US-79166710-A
Country	US
Kind code	B2
Filing date	Jun 1, 2010
Priority date	Jun 30, 2009
Publication date	Mar 1, 2016
Grant date	Mar 1, 2016

Abstract

A touch detection device includes: a detection surface; a plurality of sensor lines formed from a plurality of types of wiring lines having a different line capacitance; and a touch detection unit which detects an electric variation generated in a plurality of the sensor lines in response to touch or proximity of a detection target object to the detection surface, wherein the touch detection unit has an operational circuit for generating a detection signal representing the electric variation by performing an operation process using a line capacitance ratio for a plurality of outputs from a plurality of types of the sensor lines neighboring to one another with a different line capacitance.

First claim

What is claimed is:

1. A touch detection device comprising:
a detection surface;
a plurality of sensor lines formed from a plurality of wiring lines, wherein a plurality of adjacent independent sensor lines are sequentially varying sensor lines, each sensor line of the sequence of adjacent sensor lines having a substantially different length and a corresponding substantially different capacitance than a preceding sensor line in the sequence; and
a touch detection unit that detects an electric variation generated in a plurality of the sensor lines associated with touch or proximity of a detection target object to the detection surface,
wherein the touch detection unit has an operational circuit for generating a detection signal corresponding to the detected electric variation at the plurality of the adjacent independent sensor lines.

2. The touch detection device according to claim 1 , wherein a plurality of the sensor lines are formed from a plurality of M types of wiring lines that have the different length for each type and are arranged in parallel to one another, and M sensor lines neighboring to one another are a different type.

3. The touch detection device according to claim 2 , wherein the M sensor lines are formed from wiring lines having a same material, a same thickness, a same width, and a plurality of different lengths,
wherein each of the M sensor lines has a length which is a K multiple (where, K=1 to N) of a length L of an elementary sensor line having a shortest length, and
wherein the operational circuit obtains the detection signal by selecting two sensor lines including a longest sensor line from the M sensor lines, sampling two outputs from the two sensor lines at a timing corresponding to a ratio of the lengths of the two selected sensor lines, and performing a difference operation for sampling values.

4. The touch detection device according to claim 3 , wherein the coefficients M and N are set to 3.

5. The touch detection device according to claim 2 , wherein the M sensor lines are formed from wiring lines having a same material, a same thickness, a same width, and a plurality of different lengths,
wherein each of the M sensor lines has a length which is a K multiple (where, K=1 to N) of a length L of an elementary sensor line having a shortest length, and
wherein the operational circuit obtains the detection signal by selecting two sensor lines from the M sensor lines, obtaining a difference of outputs for the two selected sensor lines of which a ratio of lengths is set to k (where, k is a natural number equal to or larger than 2), and removing the obtained difference with (k−1).

6. The touch detection device according to claim 2 , wherein one of the operation circuits and another operation circuit are connected to the same sensor line, and different types of sensor lines are arranged in symmetry with respect to the sensor line common to the two operational circuits.

7. The touch detection device according to claim 2 , wherein the different types of M sensor lines are periodically repeatedly arranged.

8. The touch detection device according to claim 1 , wherein a plurality of the sensor lines are formed from a plurality of M types of wiring lines that have the different length for each type and are arranged in parallel to one another, and wherein the touch detection device further includes
a plurality of driving electrodes, each of which is capacitively coupled to a plurality of the sensor lines, arranged in parallel to extend in a direction different from that of a plurality of the sensor lines, and
a scan driving unit that sequentially voltage-driving (scanning) a plurality of the driving electrodes from a driving electrode of one end to a driving electrode of the other end.

9. The touch detection device according to claim 7 , wherein the touch detection unit obtains a position of the detection target object based on the detection signal generated from the operational circuit and time information synchronized with the scanning of the scan driving unit.

10. The touch detection device according to claim 2 , wherein each of the operational circuits for each of the M sensor lines that neighbor to one another and have a different type includes a reset switch for simultaneously resetting electric potentials of the sensor lines in all of the operational circuits.

11. The touch detection device according to claim 2 , further comprising a conductive layer for shielding a sensor line of a type having a shortest length out of the M sensor lines.

12. A display device having a touch sensor function, the display device comprising:
a display surface;
a plurality of image signal lines;
a display function layer that changes display of the display surface in response to signal voltages applied to a plurality of the image signal lines;
a plurality of sensor lines formed from wiring lines, wherein a plurality of adjacent independent sensor lines are sequentially varying sensor lines, each sensor line of the sequence of adjacent sensor lines having a substantially different length and a corresponding substantially different capacitance than a preceding sensor line in the sequence; and
a touch detection unit that detects an electric variation generated from a plurality of the sensor lines in response to touch or proximity of a detection target object to the display surface,
wherein a plurality of the sensor lines are formed from different types of wiring lines having a different line capacitance due to the different length for each type, and
wherein the touch detection unit includes an operational circuit for generating a detection signal corresponding to the detected electric variation at the plurality of the adjacent independent sensor lines.

13. The display device according to claim 12 , wherein a plurality of the sensor lines are formed from a plurality of M types of wiring lines that have the different length for each type and are arranged in parallel to one another, and a plurality of M sensor lines neighboring to one another are a different type, and
wherein the touch detection unit has the operational circuit provided for each of the M sensor lines that neighbor to one another and are a different type.

14. The display device according to claim 13 , wherein the M sensor lines are formed from wiring lines having a same material, a same thickness, a same width, and a plurality of different lengths,
wherein each of the M sensor lines has a length which is a K multiple (where, K=1 to N) of a length L of an elementary sensor line having a shortest length, and
wherein the operational circuit obtains the detection signal by selecting two sensor lines including a longest sensor line from the M sensor lines, sampling two outputs from the two sensor lines at a timing corresponding to a ratio of the lengths of the two selected sensor lines, and performing a difference operation for sampling values.

15. The display device according to claim 13 , wherein the sensor line having a maximum length out of the M sensor lines intersects with two opposite sides of an effective display area of the display surface, and the sensor line having a minimum length out of the M sensor lines is disposed outside the effective display area.

16. A display device having a touch sensor function, the display device comprising:
a plurality of pixels connected to one another by a plurality of scanning lines and a plurality of image signal lines, each of the pixels having a switch for writing a voltage of corresponding one of the image signal lines in response to a voltage applied to corresponding one of the s

Assignees

• Ishizaki Koji
• Noguchi Kouji
• Takeuchi Takeya
• Nakanishi Takayuki
• Teranishi Yasuyuki
• Japan Display Inc

Inventors

• Ishizaki Koji
• Noguchi Kouji
• Takeuchi Takeya
• Nakanishi Takayuki
• Teranishi Yasuyuki

Classifications

• G06F3/044 Primary

  by capacitive means · CPC title

• G06F3/0445

  using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer · CPC title

• G06F3/0446

  using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes · CPC title

• G06F3/04166 Primary

  Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving (Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184) · CPC title

• G06F3/0412

  Digitisers structurally integrated in a display · CPC title