Multi-touch force sensing touch-screen devices and methods

• US 9,477,342 B2
• Filed: 08/26/2008
• Issued: 10/25/2016
• Est. Priority Date: 08/26/2008
• Status: Active Grant

• Current Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Original Assignee: Google Technology Holdings LLC (Alphabet Inc.)
• Inventors: Daverman, Dodge, Olley, Michael
• Primary Examiner(s): Sherman, Stephen
• Assistant Examiner(s): Midkiff, Aaron
• Application Number:
  US12/198,237
• Publication Number:
  US 20100053116A1
• Time in Patent Office: 2,982 Days
• Field of Search: 178/18.01, 178/18.02, 178/18.06, 345173-178
• US Class Current: 1/1
• CPC Class Codes: G06F 3/04144 using an array of force sensing means position sensing using the local deformation of sensor cells G06F3/0447
• CPC Class Codes: G06F 3/04186 Touch location disambiguation

Abstract

Described are methods and devices including a touch sensor layer configured to receive touch input and a force sensor layer stacked with the touch sensor layer, the force sensor layer includes an array of force sensors configured to receive force input. The force sensor array includes individual force sensors. Specific sensors of the disclosed force sensor array are associated with specific locations of the touch screen to add information that can be used to decipher which key is actually being pressed and may avoid falsing. Both a touch signal and a force signal are utilized to determine the validity of a user touch input. In one embodiment each force sensor may operate independently of the others. Particular embodiments are described that utilize a coarse grid to determine valid touch inputs and that make a determination of a centroid location based on a plurality of force sensors to determine valid touch inputs.

Claims

1. A user input system, comprising:

a touch sensor layer configured to receive touch inputs of a user on a touch screen, wherein the touch screen includes multiple items;

a force sensor layer, including an array of force sensors, with each of the force sensors configured to receive force inputs; and

a controller configured to;

receive a touch input received on the touch sensor layer, wherein the touch input is simultaneously received on at least two of the multiple items on the touch screen,

receive multiple force inputs from the force sensor layer with each force input being from a different one of the multiple force sensors,

generate a force value for each of the received force inputs, wherein the generated force values are each associated with a corresponding one of the force sensors,

compute a centroid location using the generated force values, wherein the centroid location is a single location that is associated with the generated force values from multiple force sensors, and

calculate a distance from each of the multiple items on the touch screen to the centroid location to validate one of the multiple items as an intended touch.

2. The system of claim 1 wherein the touch sensor layer has an area wherein a location is associated with a portion of the area of the touch sensor layer, and wherein at least one force sensor is associated with at least one location of the touch sensor layer.

3. The system of claim 2 wherein the controller is further configured to process a single force input to determine a force value for a touch input in accordance with the location of user input to the touch sensor layer as determined from processing the touch input.

4. The system of claim 1, further comprising:

a display module having an active viewing area, the display module stacked with the touch sensor layer and the force sensor layer.

5. The system of claim 4 wherein at least a portion of the array of force sensors is outside the active viewing area of the display module.

6. The system of claim 1 wherein the touch sensor layer has a resolution and wherein the touch sensor layer is divided into grid portions such that a grid portion of the touch sensor is associated with at least one force sensor in a force sensor array, wherein the grid of the touch sensor layer has a higher resolution than a grid of the force sensor layer.

7. The system of claim 1, wherein the controller is further configured to determine which sensors of the array of force sensors received force input so as to generate the force values for the sensors that received force input.

8. The system of claim 1 wherein the multiple items include multiple keys.

9. The system of claim 8 wherein the multiple keys include multiple virtual keys displayed on the touch screen.

10. A method of a user input system including a touch sensor layer and a force sensor layer including an array of force sensors, the method comprising:

receiving touch input from the touch sensor layer on a touch screen, wherein the touch screen includes multiple items;

receiving force inputs from the force sensor layer;

receiving a touch input received on the touch sensor layer, wherein the touch input is simultaneously received on at least two of the multiple items on the touch screen;

receiving multiple force inputs from the force sensor layer with each force input being from a different one of the multiple force sensors;

generating a force value for each of the received force inputs, wherein the generated force values are each associated with a corresponding one of the force sensors;

computing a centroid location using the generated force values, wherein the centroid location is a single location that is associated with the generated force values from multiple force sensors; and

calculating a distance from each of the multiple items on the touch screen to the centroid location to validate one of the multiple items as an intended touch.

11. The method of claim 10 wherein the touch screen includes an area which includes a plurality of touch screen locations and wherein particular touch screen locations are assigned to particular force sensors of the force sensor arrays, the method further comprising:

determining a force value associated with a user input in accordance with at least one force sensor assigned to a particular touch screen location when a touch input is received at the particular touch screen location.

12. The method of claim 11 further comprising:

determining whether the force value exceeds a predetermined threshold value for the location of the touch screen.

13. The method of claim 10 wherein:

the multiple items include multiple keys.

14. The method of claim 13 wherein the multiple keys include multiple virtual keys displayed on the touch screen.