Palm pressure rejection method and apparatus for touchscreens

• US 6,246,395 B1
• Filed: 12/17/1998
• Issued: 06/12/2001
• Est. Priority Date: 12/17/1998
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Company (HP Inc.)
• Inventors: Goyins, Gregg S., Resman, Mark F.
• Primary Examiner(s): Chow, Dennis-Doon
• Application Number:
  US09/215,048
• Time in Patent Office: 908 Days
• Field of Search: 345/173, 345/174, 345/175, 345/177, 345/179, 345/180, 345/156, 345/157, 178/18-1-, 178/19-1-, 341/22
• US Class Current: 345/173
• CPC Class Codes: G06F 3/0488 using a touch-screen or digitiser, e.g. input of commands through traced gestures

Abstract

There is provided a method and apparatus for categorizing substantially simultaneous inputs to a touchscreen. The method is described within a computer device having a display screen adapted to receive touchscreen input. In a first step, the display screen is divided into a plurality of sectors. Next, the sectors are sequentially scanned for input. When a plurality of substantially simultaneous inputs are sensed in respective sectors, the location by sector of each input is ascertained. A unique value is then assigned to each input received, the assigned values corresponding to the sequence in time of the respective inputs based upon the sequentially scanned sectors in which the inputs occurred. The apparatus includes a display screen adapted to receive touchscreen input. A touchscreen driver/sensor is provided to divide the display screen into a plurality of sectors and to sense input in each of the sectors. A sequence counter is used to actuate the driver/sensor to scan the display screen sectors sequentially and at predetermined intervals for input, and to assign a unique value to each input received.

Claims

1. In a computer device having a display screen adapted to receive touchscreen input, a method for categorizing substantially simultaneous inputs to a touchscreen comprising the following steps:

dividing the display screen into a plurality of sectors;

scanning the sectors sequentially for input;

sensing a plurality of substantially simultaneous inputs in respective sectors;

ascertaining the location by sector of each input; and

assigning a value to each input received, the assigned values corresponding to the sequence in time of the respective inputs based upon the sequentially scanned sectors in which the inputs occurred;

whereby the assigned values are compared to distinguish functionally significant inputs from inadvertent inputs.

2. A method according to claim 1, wherein the computer device comprises a touchscreen driver/sensor adapted and constructed to sequentially drive and sense discrete sectors of the display screen, and the step of dividing the screen into a plurality of sectors comprises actuating the driver/sensor to divide the display screen into sectors.

3. A method according to claim 2, wherein the step of dividing the screen into a plurality of sectors comprises actuating the driver/sensor to divide the display screen into sectors having substantially equal area.

4. A method according to claim 3, wherein the step of dividing the screen into a plurality of sectors comprises dividing the display screen into substantially rectilinear sectors.

5. A method according to claim 4, wherein the step of dividing the display screen into a plurality of sectors comprises actuating the driver/sensor to divide the display screen into quadrants.

6. A method according to claim 1, wherein the step of dividing the display screen into a plurality of sectors comprises actuating the driver/sensor to divide the display screen into sectors having substantially unequal area.

7. A method according to claim 1, wherein the step of dividing the screen into a plurality of sectors comprises actuating the driver/sensor to divide the display screen into substantially non-rectilinear sectors.

8. A method according to claim 1, wherein the step of assigning values to inputs received comprises using a sequence counter to assign a time value to each input.

9. A method according to claim 1, wherein the computer device comprises a touchscreen driver/sensor adapted and constructed to sequentially drive and sense discrete sectors of the display screen, and the step of scanning sectors sequentially for input comprises causing a sequence counter to actuate the driver/sensor to sequentially scan discrete sectors of the display screen at predetermined regular intervals.

10. An apparatus for categorizing substantially simultaneous inputs to a touchscreen, the apparatus comprising the following:

a display screen adapted to receive touchscreen input;

a touchscreen driver/sensor adapted and constructed to divide the display screen into a plurality of sectors and to sense input in each of the sectors; and

a sequence counter adapted and constructed to actuate the driver/sensor to scan the display screen sectors sequentially and at predetermined intervals for input, and to assign a unique value to each input received;

whereby the assigned values are compared to distinguish functionally significant inputs from inadvertent inputs.

11. An apparatus according to claim 10, wherein the driver/sensor is adapted and constructed to divide the display screen into sectors having substantially equal area.

12. An apparatus according to claim 11, wherein the driver/sensor is adapted and constructed to divide the display screen into a plurality of substantially rectilinear sectors.

13. An apparatus according to claim 12, wherein the driver/sensor is adapted and constructed to divide the display screen into quadrants.

14. An apparatus according to claim 10, wherein the driver/sensor is adapted and constructed to divide the display screen into sectors having substantially unequal area.

15. An apparatus according to claim 10, wherein the driver/sensor is adapted and constructed to divide the display screen into substantially non-rectilinear sectors.

16. An apparatus for categorizing substantially simultaneous inputs to a touchscreen, the apparatus comprising the following:

a display screen adapted to receive touchscreen input;

a touchscreen driver/sensor adapted and constructed to divide the display screen into a plurality of sectors and to sense input in each of the sectors;

a sequence counter adapted and constructed to actuate the driver/sensor to scan the display screen sectors sequentially and at predetermined intervals for input, and to assign a unique value to each input received; and

a processor adapted and constructed to receive input sector location data from the driver/sensor and input time sequence data from the sequence counter, and to manipulate the location and time sequence data for the inputs to classify the inputs;

whereby the manipulation of data by the processor distinguishes functionally significant inputs from inadvertent inputs.

17. An apparatus according to claim 16, wherein the touchscreen driver/sensor comprises a multi-channel driver sensor, with the number of channels corresponding to the number of sectors into which the display screen is divided.

18. An apparatus according to claim 16, further comprising:

a multi-channel analog demultiplexer connected to the driver/sensor.

19. An apparatus according to claim 17, further comprising:

an analog-to-digital converter connected to the demultiplexer.

20. An apparatus according to claim 16, wherein the sequence counter is connected to the driver/sensor and the demultiplexer such that the sequence counter controls actuation of the driver/sensor and the demultiplexer.