US Patent No. 10,338,739

METHODS AND APPARATUS TO DETECT A PRESENCE OF A CONDUCTIVE OBJECT


Patent No. 10,338,739
Issue Date July 02, 2019
Title Methods And Apparatus To Detect A Presence Of A Conductive Object
Inventorship Jonathan R Peterson, Everett, WA (US)
Cole D. Wilson, Everett, WA (US)
Thomas Fuller, Seattle, WA (US)
Derek James Valleroy, Seattle, WA (US)
Assignee Cypress Semiconductor Corporation, San Jose, CA (US)

Claim of US Patent No. 10,338,739

1. A method of stabilizing detected presence, comprising:responsive to a first scan operation by a capacitive sensor, detecting a first presence of a conductive object based on a first plurality of regions of a device interface having changes in sensor values that meet or exceed a threshold value;
determining a three dimensional shape for the detected first presence, the three dimensional shape comprising the first plurality of regions of the device interface having the changes in sensor values that meet or exceed the threshold value and a second plurality of regions of the device interface not having changes in sensor values that meet the threshold value;
using a processing device, calculating modified changes in sensor values for the second plurality of regions, based on a surface of the three dimensional shape, wherein the modified changes in sensor values meet the surface of the three dimensional shape;
responsive to a second scan operation by the capacitive sensor, detecting a second presence of the conductive object based on a third plurality of regions of the device interface having changes in sensor values that meet or exceed the threshold value, wherein a difference between the changes in sensor values of the detected first presence and the detected second presence is caused by at least one of electrical noise and movement of the conductive object;
using the processing device, assigning the three dimensional shape to the detected second presence; and
calculating a coordinate position of the detected first presence and the detected second presence based on the three dimensional shape.