INPUT DETECTION DEVICE AND ELECTRONIC DEVICE

• US 20170357368A1
• Filed: 06/09/2017
• Published: 12/14/2017
• Est. Priority Date: 06/10/2016
• Status: Active Grant

• Current Assignee: Wacom Co Limited (Wacom)
• Original Assignee: Japan Display Incorporated
• Inventors: KATSUTA, Tadayoshi, MIZUHASHI, Hiroshi
• Granted Patent: US 10,444,895 B2
• Time in Patent Office: Days
• CPC Class Codes: G02F 1/13338 Input devices, e.g. touch panels
• CPC Class Codes: G06F 2203/04106 Multi-sensing digitiser, i.e. digitiser using at least two different sensing technologies simultaneously or alternatively, e.g. for detecting pen and finger, for saving power or for improving position detection
• CPC Class Codes: G06F 2203/04108 Touchless 2D- digitiser, i.e. digitiser detecting the X/Y position of the input means, finger or stylus, also when it does not touch, but is proximate to the digitiser's interaction surface without distance measurement in the Z direction
• CPC Class Codes: G06F 3/03545 Pens or stylus
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04166 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 Class Codes: G06F 3/0445 using two or more layers of sensing electrodes, e.g. using two layers of electrodes separated by a dielectric layer
• CPC Class Codes: G06F 3/0446 using a grid-like structure of electrodes in at least two directions, e.g. using row and column electrodes
• CPC Class Codes: G06F 3/046 by electromagnetic means

Abstract

An input detection device includes a plurality of drive electrodes which are arranged in parallel to each other in plan view, and each of which has a pair of ends. At least one drive electrode among the plurality of drive electrodes is driven such that a first drive state where a first drive voltage is supplied to one end of the drive electrode and a second drive voltage different from the first drive voltage is supplied to the other end of the drive electrode and a second drive state where the second drive voltage is supplied to the one end and the first drive voltage is supplied to the other end temporally alternately occur.

Claims

1. An input detection device comprising:

a plurality of drive electrodes which are arranged in parallel to each other in plan view and each of which includes a pair of ends,

wherein at least one first drive electrode among the plurality of drive electrodes is configured to be driven such that a first drive state and a second drive state temporally alternately occur,

the first drive state is a state where a first drive voltage is supplied to one end of the first drive electrode and a second drive voltage different from the first drive voltage is supplied to the other end of the first drive electrode, and

the second drive state is a state where the second drive voltage is supplied to the one end and the first drive voltage is supplied to the other end.

2. The input detection device according to claim 1,

wherein the plurality of drive electrodes include a second drive electrode which is arranged in parallel to the first drive electrode,

the second drive electrode is configured to be is brought into the second drive state where the second drive voltage is supplied to one end of the second drive electrode and the first drive voltage is supplied to the other end of the second drive electrode when the first drive electrode is in the first drive state, and

the second drive electrode is configured to be brought into the first drive state where the first drive voltage is supplied to the one end of the second drive electrode and the second drive voltage is supplied to the other end of the second drive electrode when the first drive electrode is in the second drive state.

3. The input detection device according to claim 2,

wherein the plurality of drive electrodes include a third drive electrode which is arranged between the first drive electrode and the second drive electrode, and

since each of the first drive electrode and the second drive electrode is temporally alternately brought into the first drive state and the second drive state, a magnetic field generated by the first drive electrode and a magnetic field generated by the second drive electrode overlap in a region where the third drive electrode is arranged.

4. The input detection device according to claim 1,

wherein the input detection device includes a magnetic field generation period in which a magnetic field is generated by the first drive electrode, and a magnetic field detection period in which a magnetic field generated by an external object is detected according to the magnetic field generated in the magnetic field generation period, and

the first drive electrode is configured to be driven such that each of the first drive state and the second drive state occurs once or more times in the magnetic field generation period.

5. The input detection device according to claim 1,

wherein the input detection device is configured to drive the first drive electrode to be in the second drive state at a timing when a change amount of a current flowing through the first drive electrode becomes less than a predetermined value when the first drive electrode is driven to be in the first drive state.

6. The input detection device according to claim 1,

wherein the input detection device is configured to drive the first drive electrode to be in the second drive state at a timing when a current flowing through the first drive electrode becomes steady when the first drive electrode is driven to be in the first drive state.

7. The input detection device according to claim 2,

wherein each of the first drive electrode and the second drive electrode is configured to be temporally alternately driven to be in the first drive state and the second drive state, and thus, a direction of a current flowing through each of the first drive electrode and the second drive electrode changes, and a direction of a magnetic field generated at each of the first drive electrode and the second drive electrode changes.

8. The input detection device according to claim 1,

wherein the first drive electrode includes a plurality of adjacent drive electrodes.

9. The input detection device according to claim 2, further comprising:

a first unit scanner circuit and a second unit scanner circuit which are arranged in proximity to the one ends of the plurality of drive electrodes;

a first selection drive circuit which is configured to supply the first drive voltage to one end of a drive electrode selected by the first unit scanner circuit and supply the second drive voltage to one end of a drive electrode selected by the second unit scanner circuit;

a third unit scanner circuit and a fourth unit scanner circuit which are arranged in proximity to the other ends of the plurality of drive electrodes; and

a second selection drive circuit which is configured to supply the first drive voltage to the other end of a drive electrode selected by the third unit scanner circuit and supply the second drive voltage to the other end of a drive electrode selected by the fourth unit scanner circuit,

wherein the first unit scanner circuit and the fourth unit scanner circuit is configured to select an identical drive electrode from among the plurality of drive electrodes as the first drive electrode, and

the second unit scanner circuit and the third unit scanner circuit is configured to select an identical drive electrode from among the plurality of drive electrodes as the second drive electrode.

10. The input detection device according to claim 9,

wherein each of the first unit scanner circuit, the second unit scanner circuit, the third unit scanner circuit, and the fourth unit scanner circuit includes a shift register which has a plurality of shift stages connected in series,

the shift register is configured to shift selection information indicating selection of a drive electrode according to a shift clock signal,

a position of a shift stage which stores the selection information in the shift register of the first unit scanner circuit is apart from a position of a shift stage which stores the selection information in the shift register of the second unit scanner circuit,

the first selection drive circuit is configured to supply the first drive voltage and the second drive voltage to the drive electrodes corresponding to the positions of the shift stages which store the selection information in the first unit scanner circuit and the second unit scanner circuit,

a position of a shift stage which stores the selection information in the shift register of the third unit scanner circuit is apart from a position of a shift stage which stores the selection information in the shift register of the fourth unit scanner circuit, and

the second selection drive circuit is configured to supply the second drive voltage and the first drive voltage to the drive electrodes corresponding to the positions of the shift stages which store the selection information in the third unit scanner circuit and the forth unit scanner circuit.

11. The input detection device according to claim 10, further comprising:

a first register which is configured to store information determining a shift quantity by which the positions of the shift stages are apart.

14. An electronic device comprising:

an input detection device according to claim 1.

15. The input detection device according to claim 2,

wherein the plurality of drive electrodes include a third drive electrode which is arranged between the first drive electrode and the second drive electrode, and

the third drive electrode is configured to be brought into a floating potential when each of the first drive electrode and the second drive electrode is temporally alternately brought into the first drive state and the second drive state.

16. The input detection device according to claim 1, further comprising a plurality of pixels,

wherein, in each pixel, a display drive signal is supplied to the drive electrode.

17. The input detection device according to claim 1, further comprising:

a scan line; and

a signal line,

wherein at least one of the scan line and the signal line is configured to be brought into a floating potential when the drive electrode becomes at least one of the first drive state and the second drive state.

12. An input detection device generating a magnetic field by making a current flow through a drive electrode,

wherein the drive electrode includes one end and the other end, and

a first drive state where a current flows from the one end to the other end and a second drive state where a current flows from the other end to the one end temporally alternately occur in an identical drive electrode, and thus, a direction of a magnetic field generated by the drive electrode is reversed at a time interval.

13. The input detection device according to claim 12, comprising:

a first substrate on which the drive electrode is formed,

a second substrate which is mounted on the first substrate; and

a detection electrode which is formed on the second substrate and is arranged to cross the drive electrode in plan view,

wherein a magnetic field generated by an external object is detected according to the magnetic field by the detection electrode.

18. An input detection device comprising:

a plurality of drive electrodes which include at least one first drive electrode and are arranged on a first substrate;

a first selection drive circuit which is arranged in proximity to one ends of the plurality of drive electrodes;

a second selection drive circuit which is arranged in proximity to the other ends of the plurality of drive electrodes;

wherein, in a first period, the first selection drive circuit is configured to supply a first drive voltage to one end of the first drive electrode, and

the second selection drive circuit is configured to supply a second drive voltage which is different from the first drive voltage to the other end of the first drive electrode, and

in a second period which is different from the first period, the first selection drive circuit is configured to supply the second drive voltage to the one end of the first drive electrode, and

the second selection drive circuit is configured to supply the first drive voltage to the other end of the first drive electrode.