Contact Detection Mode Switching in a Touchscreen Device
AssigneeCypress Semiconductor Corporation
InventorsHan Wang, Petro Ksondzyk, Chris Chen
Life of this patent
Estimating the term…
Abstract
A method is disclosed for determining detecting a conductive object and determining the type of object and the type of contact that object has with a touch sensitive surface, the method comprising measuring capacitance on a plurality of mutual capacitance sensors, each mutual capacitance sensor corresponding to a unit cell in an array of unit cells. After mutual capacitance is measured a peak unit cell is identified based on the measured capacitances and a matrix sum of a plurality of unit cells surround the peak unit cell is calculated. The value of the peak unit cell and the matrix sum are then compared to a range and a contact type determined based on the comparison.
Claims20
A method comprising:
- measuring capacitance on a plurality of mutual capacitance sensors, each mutual capacitance sensor corresponding to a unit cell in an array of unit cells;
- identifying a peak unit cell based on the measured capacitances;
- calculating a matrix sum of a plurality of unit cells surrounding each identified peak unit cell;
- identifying a range into which a value of the peak unit cell and the matrix sum may be placed;
- and
- determining an contact type based on the identifying range.
A user interface device comprising:
- a first plurality capacitance sensing electrodes disposed along a first axis of an array of unit cells;
- a second plurality of capacitance sensing electrodes disposed along a second axis of an array unit cells;
- and
- a controller configured to:
- measure capacitance on a plurality of mutual capacitance sensors, each mutual capacitance sensor associated with a unit cell in an array of unit cells;
- identify a peak unit cell based on the measured capacitances;
- calculate a matrix sum of a plurality of unit cells surrounding each identified peak unit cell;
- identify a range into which a value of the peak unit cell and the matrix sum may be placed;
- and
- determine an contact type based on the identifying range.
A user interface device 9, wherein the plurality of contact identification types includes at least one of a bare finger, a gloved finger, a stylus, and a contact hovering above the array.
A touchscreen controller configured to:
- measure capacitance on a plurality of mutual capacitance sensors, each mutual capacitance sensor represented as a unit cell in an array of unit cells;
- identify a peak unit cell based on the measured capacitances;
- calculate a matrix sum of a plurality of unit cells surrounding each identified peak unit cell;
- identify a range into which a value of the peak unit cell and the matrix sum may be placed;
- and
- determine an contact type based on the identifying range.
Dependencies are inferred from the claim text.