Ultrasonic imaging with acoustic resonant cavity
First Claim
1. A method for generating an image of a target object, comprising:
- applying a plurality of excitation signal pulses to an ultrasonic transmitter of an ultrasonic sensor unit, wherein a frequency of the plurality of excitation signal pulses is selected to generate an ultrasonic standing wave inside a cover glass layer of a stack of material layers, the cover glass layer configured for contact with the target object, and wherein the plurality of excitation signal pulses are applied for a duration to allow buildup of energy for the ultrasonic standing wave over a first threshold level;
detecting a change in one or more characteristics of the ultrasonic standing wave associated with an interaction between the ultrasonic standing wave and the target object using an ultrasonic receiver of the ultrasonic sensor unit; and
generating the image of the target object based on the detected change in the one or more characteristics of the ultrasonic standing wave.
1 Assignment
0 Petitions
Accused Products
Abstract
Techniques describe structures and methods for generating larger output signals and improving image quality of ultrasonic sensors by inclusion of an acoustic cavity in the sensor stack. In some embodiments, an ultrasonic sensor unit may be tuned during manufacturing or during a provisioning phase to work with different thicknesses and materials. In some embodiments, a standing wave signal may be generated using an acoustic cavity in the ultrasonic sensor unit for capturing an ultrasonic image of an object placed on a sensor surface. In some implementations, the ultrasonic sensor may include an ultrasonic transmitter, a piezoelectric receiver, a thin film transistor (TFT) layer and a TFT substrate positioned between the transmitter and the receiver, one or more adhesive layers, and optional cover materials and coatings. The thickness, density and speed of sound of the sensor materials and associated adhesive attachment layers may be used to attain the desired acoustic cavity and improved performance.
-
Citations
30 Claims
-
1. A method for generating an image of a target object, comprising:
-
applying a plurality of excitation signal pulses to an ultrasonic transmitter of an ultrasonic sensor unit, wherein a frequency of the plurality of excitation signal pulses is selected to generate an ultrasonic standing wave inside a cover glass layer of a stack of material layers, the cover glass layer configured for contact with the target object, and wherein the plurality of excitation signal pulses are applied for a duration to allow buildup of energy for the ultrasonic standing wave over a first threshold level; detecting a change in one or more characteristics of the ultrasonic standing wave associated with an interaction between the ultrasonic standing wave and the target object using an ultrasonic receiver of the ultrasonic sensor unit; and generating the image of the target object based on the detected change in the one or more characteristics of the ultrasonic standing wave. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12)
-
-
13. An ultrasonic sensor system, comprising:
-
a stack of material layers including a cover glass layer, the cover glass layer configured for contact with a target object; and an ultrasonic transmitter in acoustic contact with the stack of material layers, the ultrasonic transmitter configured to receive a plurality of excitation signal pulses, wherein a frequency of the received excitation signal pulses is selected to generate an ultrasonic standing wave inside the cover glass layer and wherein the excitation signal pulses are received for a duration to allow buildup of energy in the ultrasonic standing wave over a first threshold level. - View Dependent Claims (14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24)
-
-
25. An ultrasonic sensor system, comprising:
-
means for applying a plurality of excitation signal pulses to an ultrasonic transmitter of an ultrasonic sensor unit, wherein a frequency of the excitation signal pulses is selected to generate an ultrasonic standing wave inside a cover glass layer of a stack of material layers and wherein the excitation signal pulses are applied for a duration to allow buildup of energy for the ultrasonic standing wave over a first threshold level; means for detecting a change in one or more characteristics of the ultrasonic standing wave associated with an interaction between the ultrasonic standing wave and a target object; and
means for generating an image of the target object based on the detected change in the one or more characteristics of the ultrasonic standing wave. - View Dependent Claims (26, 27, 29, 30)
-
-
28. A non-transitory computer-readable storage medium, wherein the non-transitory computer-readable storage medium comprises instructions executable by a processor to:
-
apply a plurality of excitation signal pulses to an ultrasonic transmitter of an ultrasonic sensor unit, wherein a frequency of the plurality of excitation signal pulses is selected to generate an ultrasonic standing wave inside a cover glass layer of the stack of material layers, the cover glass layer configured for contact with a target object, and wherein the plurality of excitation signal pulses are applied for a duration to allow buildup of energy for the ultrasonic standing wave over a first threshold level; detect a change in one or more characteristics of the ultrasonic standing wave associated with an interaction between the ultrasonic standing wave and the target object using an ultrasonic receiver of the ultrasonic sensor unit; and generate the image of the target object based on the detected change in the one or more characteristics of the ultrasonic standing wave.
-
Specification