Image generation in an electronic device using ultrasonic transducers

An electronic device comprising:

• an ultrasonic sensor;
• a processing logic module;
• and
• a processor connected to the processing logic module and configured to perform the steps of:
• capturing a first set of image pixels by an ultrasonic sensor comprising an array of ultrasonic transducers using a first beamforming pattern, wherein the first beamforming pattern comprises a first pattern of transmit signals routed to a plurality of ultrasonic transducers of the ultrasonic sensor, wherein the first beamforming pattern activates transducers with different signal delays, to focus each beam to a single point over the ultrasonic sensor,
• capturing a second set of image pixels by the ultrasonic sensor using a second beamforming pattern, wherein the second beamforming pattern comprises a second pattern of transmit signals routed to the plurality of ultrasonic transducers, wherein the second beamforming pattern is different than the first beamforming pattern, wherein the second beamforming pattern activates different transducers with different signal delays, to focus each beam to a single point over the ultrasonic sensor, and wherein the second set of pixels corresponds to an edge region of the ultrasonic sensor, and
• combining the first set of image pixels and the second set of image pixels to form an image.

A method of generating an image of a fingerprint with a fingerprint sensor comprising an ultrasonic sensor comprising a plurality of ultrasonic transducers to transmit a first ultrasonic beam from sets of ultrasonic transducers toward a surface configured to receive a finger having the fingerprint thereon and to receive a second ultrasonic beam reflected from the fingerprint, the second ultrasonic beam to generate a signal for processing in a signal processor, the method comprising:

• capturing a first set of image pixels by an ultrasonic sensor comprising an array of ultrasonic transducers using a first beamforming pattern, wherein the first beamforming pattern comprises a first pattern of transmit signals routed to a plurality of ultrasonic transducers of the ultrasonic sensor, wherein the first set of image pixels comprises pixels corresponding to an edge region of the ultrasonic sensor;
• capturing a second set of image pixels by the ultrasonic sensor using a second beamforming pattern, wherein the second beamforming pattern comprises a second pattern of transmit signals routed to the plurality of ultrasonic transducers, wherein the second beamforming pattern is different than the first beamforming pattern, and wherein the second set of image pixels corresponds to the edge region of the ultrasonic sensor;
• and
• combining the first set of image pixels and the second set of image pixels to form the image, wherein the combining the first set of image pixels and the second set of image pixels to form the image comprises:
• replacing pixels of the first set of image pixels corresponding to the edge region with the second set of image pixels to form the image.