Method and system for input object separation using pixel response functions

An input device, comprising:

• a plurality of transmitter electrodes configured to transmit one or more sensing signals;
• a plurality of receiver electrodes configured to obtain a plurality of resulting signals in response to transmitting the one or more sensing signals;
• and
• a processing system operatively connected to the plurality of receiver electrodes and the plurality of transmitter electrodes, the processing system configured to:
• obtain, from the plurality of resulting signals, a capacitive image of a plurality of sensor pixels among the plurality of receiver electrodes,
• obtain a plurality of pixel response functions corresponding to the plurality of sensor pixels,
• determine, from the capacitive image and using a search method and the plurality of pixel response functions, a first plurality of capacitive contributions of a first input object and a second plurality of capacitive contributions of a second input object,
• compare, using the plurality of pixel response functions and with the capacitive image, the first plurality of capacitive contributions and the second plurality of capacitive contributions to produce a comparison,
• determine, based at least in part on the comparison, whether the first plurality of capacitive contributions and the second plurality of capacitive contributions satisfy a predetermined criterion,
• update, using the search method, the first plurality of capacitive contributions and the second plurality of capacitive contributions in response to failing to satisfy the predetermined criterion, and
• determine, using the first plurality of capacitive contributions and the second plurality of capacitive contributions, a first location of the first input object and a second location of the second input object.

A method, comprising:

• obtaining a capacitive image of a plurality of sensor pixels in an input device, wherein the capacitive image comprises a plurality of capacitive measurements resulting from a first input object and a second input object in a sensing region of the input device;
• and
• obtaining a plurality of pixel response functions corresponding to the plurality of sensor pixels;
• determining, from the capacitive image and using a search method and the plurality of pixel response functions, a first plurality of capacitive contributions of the first input object in the capacitive image and a second plurality of capacitive contributions of the second input object;
• comparing, with the capacitive image, the first plurality of capacitive contributions and the second plurality of capacitive contributions to produce a comparison;
• determining, based at least in part on the comparison, whether the first plurality of capacitive contributions and the second plurality of capacitive contributions satisfy a predetermined criterion;
• updating, using the search method, the first plurality of capacitive contributions and the second plurality of capacitive contributions in response to failing to satisfy the predetermined criterion;
• and
• determining, using the first plurality of capacitive contributions and the second plurality of capacitive contributions, a first location of the first input object and a second location of the second input object.