Synaptics Incorporated
Defensive measures for residue re-imaging

Abstract:

An input device includes a biometric sensor and a processing system. The biometric sensor is configured to capture images of a sensing region of the input device. The processing system is configured to acquire a first image of the sensing region in response to a first authentication trigger, and to acquire a second image of the sensing region in response to a second authentication trigger. The processing system is further configured to determine an amount of similarity between the first image and the second image, and to validate the second image for user authentication when the amount of similarity between the first image and the second image is below a threshold level.