LAYER FOR INDUCING VARYING DELAYS IN ULTRASONIC SIGNALS PROPAGATING IN ULTRASONIC SENSOR

• US 20190102046A1
• Filed: 11/30/2017
• Published: 04/04/2019
• Est. Priority Date: 09/29/2017
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: MIRANTO, James Anthony, Kitchens, Jack Conway, Gojevic, Stephen Michael, Campbell, Todd, Potter, Stephen James, Pezanoski, Steven
• Granted Patent: US 11,086,453 B2
• Time in Patent Office: Days
• CPC Class Codes: B06B 1/0207 Driving circuits specially adapted for particular applications, see the relevant subclass, e.g. G01; circuits for steering transducer arrays G10K11/34; basic circuits H03
• CPC Class Codes: B06B 1/0622 on one surface
• CPC Class Codes: B06B 1/0629 Square array
• CPC Class Codes: B06B 1/0688 with foil-type piezoelectric elements, e.g. PVDF
• CPC Class Codes: B06B 2201/20 Application to multi-element transducer
• CPC Class Codes: B06B 2201/56 Foil type, e.g. PVDF
• CPC Class Codes: B06B 2201/70 Specific application
• CPC Class Codes: G01H 11/08 using piezoelectric devices
• CPC Class Codes: G01S 15/8913 using separate transducers for transmission and reception
• CPC Class Codes: G01S 15/8925 the array being a two-dimensional transducer configuration, i.e. matrix or orthogonal linear arrays
• CPC Class Codes: G01S 7/5202 for pulse systems
• CPC Class Codes: G01S 7/52026 Extracting wanted echo signals Doppler systems G01S15/50; Doppler short range imaging systems G01S15/8979
• CPC Class Codes: G01S 7/52079 Constructional features constructional features of transducers B06B; mounting transducers G10K11/00; constructional features of ultrasonic medical diagnostic devices A61B8/44
• CPC Class Codes: G01S 7/52085 Details related to the ultrasound signal acquisition, e.g. scan sequences control of medical diagnostic ultrasound devices A61B8/54
• CPC Class Codes: G06F 1/1626 with a single-body enclosure integrating a flat display, e.g. Personal Digital Assistants [PDAs]
• CPC Class Codes: G06F 1/1643 the display being associated to a digitizer, e.g. laptops that can be used as penpads details related to the relative motion of the display enclosure with respect to the body enclosure, e.g. to move between laptop and tablet PC configuration G06F1/1615
• CPC Class Codes: G06F 1/169 the I/O peripheral being an integrated pointing device, e.g. trackball in the palm rest area, mini-joystick integrated between keyboard keys, touch pads or touch stripes G06F1/1643 takes precedence; constructional details of pointing devices G06F3/033
• CPC Class Codes: G06F 2203/04104 Multi-touch detection in digitiser, i.e. details about the simultaneous detection of a plurality of touching locations, e.g. multiple fingers or pen and finger
• CPC Class Codes: G06F 3/0412 Digitisers structurally integrated in a display
• CPC Class Codes: G06F 3/04166 Details of scanning methods, e.g. sampling time, grouping of sub areas or time sharing with display driving Synchronisation with the driving of the display or the backlighting unit to avoid interferences generated internally G06F3/04184
• CPC Class Codes: G06F 3/0433 : in which the acoustic waves are either generated by a movable member and propagated within a surface layer or propagated within a surface layer and captured by a movable member
• CPC Class Codes: G06F 3/0436 : in which generating transducers and detecting transducers are attached to a single acoustic waves transmission substrate
• CPC Class Codes: G06V 40/1306 : non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: H04L 63/0861 : using biometrical features, e.g. fingerprint, retina-scan cryptographic mechanisms or cryptographic arrangements for entity authentication using biological data H04L9/3231
• CPC Class Codes: H04W 12/06 : Authentication

Abstract

An apparatus includes an ultrasonic transmitter, an ultrasonic receiver, and an acoustic delay gradient layer disposed in an acoustic path between the ultrasonic transmitter and the ultrasonic receiver. The acoustic delay gradient layer is configured to cause a reflection from a platen interface of the transmitted ultrasonic signal to reach the first receiver region at a first time and the reflection from the platen interface of the transmitted ultrasonic signal to reach the second receiver region at a second time that is different from the first time. The apparatus can further include a controller configured to set for a first region or portion of the receiver, a first range gate window (RGW). The controller is also configured to set, for a second region or portion of the receiver, a second RGW, and to establish a first temporal delay between the first RGW and the second RGW.

Claims

1. An apparatus comprising:

an ultrasonic transmitter configured to transmit an ultrasonic signal towards a platen interface;

an ultrasonic receiver comprising a plurality of receiver regions within the ultrasonic receiver, the plurality of receiver regions including at least a first receiver region and a second receiver region, the ultrasonic receiver configured to receive a reflection of the transmitted ultrasonic signal from the platen interface; and

an acoustic delay gradient layer disposed in an acoustic path between the ultrasonic transmitter and the ultrasonic receiver, the acoustic delay gradient layer configured to cause the reflection from the platen interface of the transmitted ultrasonic signal to reach the first receiver region at a first time and the reflection from the platen interface of the transmitted ultrasonic signal to reach the second receiver region at a second time that is different from the first time.

2. The apparatus of claim 1, wherein the acoustic delay gradient layer comprises a tapered layer having a taper angle, the taper angle of the tapered layer causing the reflection from the platen interface to reach the first receiver region after propagating over a first physical distance and the tapered layer causing the reflection from the platen interface to reach the second receiver region after propagating over a second physical distance different from the first physical distance.

3. The apparatus of claim 2, wherein the taper angle is less than a ten degree angle.

4. The apparatus of claim 1, wherein the acoustic delay gradient layer comprises a first acoustic delay gradient layer region corresponding to the first receiver region and a second acoustic delay gradient layer region corresponding to the second receiver region and wherein a first speed of sound propagating in the first acoustic delay gradient layer region and a second speed of sound propagating in the second acoustic delay gradient layer region are different.

5. The apparatus of claim 4, wherein the acoustic delay gradient layer comprises a first material in the first acoustic delay gradient layer region and a second material in the second acoustic delay gradient layer region.

6. The apparatus of claim 4, wherein the acoustic delay gradient layer comprises a glass layer and the glass layer in the first acoustic delay gradient layer region has a doping that is different from a doping of the glass layer in the second acoustic delay gradient layer region.

7. The apparatus of claim 1, wherein the acoustic delay gradient layer is disposed between the ultrasonic transmitter and the ultrasonic receiver.

8. The apparatus of claim 1, wherein the receiver is closer to the platen interface than the ultrasonic transmitter.

9. The apparatus of claim 1, wherein the ultrasonic transmitter is a non-segmented transmitter configured to transmit the ultrasonic signal towards the platen interface across an entirety of the non-segmented transmitter simultaneously.

10. The apparatus of claim 1, further comprising a controller configured to enable the first receiver region to measure the reflection of the transmitted ultrasonic signal during a first window beginning at a first window begin time and to enable the second receiver region to measure the reflection of the transmitted ultrasonic signal during a second window beginning at a second window begin time different from the first window begin time.

11. The apparatus of claim 10, wherein

the controller configured to enable the first receiver region to measure the reflection of the transmitted ultrasonic signal during a first window beginning at the first window begin time comprises the controller configured to control an application of a sample voltage to a receiver bias electrode corresponding to the first receiver region during a first range gate window beginning at the first window begin time, and

the controller configured to enable the second receiver region to measure the reflection of the transmitted ultrasonic signal during a second window beginning at the second window begin time comprises the controller configured to control the application of the sample voltage to a receiver bias electrode corresponding to the second receiver region during a second range gate window beginning at the second window begin time.

12. The apparatus of claim 1, wherein the apparatus is disposed within a mobile device.

13. A method for operating an ultrasonic sensor, the method comprising:

transmitting, by an ultrasonic transmitter of the ultrasonic sensor, an ultrasonic signal toward a platen interface of the ultrasonic sensor along an acoustic path that includes an acoustic delay gradient layer;

receiving a reflection of the transmitted ultrasonic signal reflected from the platen interface at a first receiver region of an ultrasonic receiver of the ultrasonic sensor at a first time; and

receiving the reflection of the transmitted ultrasonic signal reflected from the platen interface at a second receiver region of the ultrasonic receiver at a second time different from the first time.

14. The method of claim 13, wherein the transmitting the ultrasonic signal towards the platen interface comprises transmitting the ultrasonic signal through a tapered acoustic delay gradient layer having a taper angle, the taper angle causing the reflection from the platen interface to reach the first receiver region after propagating over a first physical distance and the tapered angle causing the reflection from the platen interface to reach the second receiver region after propagating over a second physical distance different from the first physical distance.

15. The method of claim 13, wherein the transmitting the ultrasonic signal toward the platen interface comprises transmitting the ultrasonic signal through a first acoustic delay gradient layer region corresponding to the first receiver region at a first speed of sound and transmitting the ultrasonic signal through a second acoustic delay gradient layer region corresponding to the second receiver region at a second speed of sound different from the first speed of sound.

16. The method of claim 13, wherein the transmitting the ultrasonic signal toward the platen interface comprises transmitting the ultrasonic signal through the acoustic delay gradient layer disposed between the ultrasonic transmitter and the ultrasonic receiver.

17. The method of claim 13, wherein the transmitting the ultrasonic signal toward the platen interface comprises transmitting the ultrasonic transmitter using a non-segmented transmitter configured to transmit the ultrasonic signal towards the platen interface across an entirety of the non-segmented transmitter simultaneously.

18. The method of claim 13, wherein

the receiving the reflection of the transmitted ultrasonic signal at the first receiver region at the first time comprises enabling the first receiver region to measure the reflection of the transmitted ultrasonic signal during a first window beginning at a first window begin time;

and

the receiving the reflection of the transmitted ultrasonic signal at the second receiver region at the second time comprises enabling the second receiver region to measure the reflection of the transmitted ultrasonic signal during a second window beginning at a second window begin time different from the first window begin time.

19. The method of claim 18, wherein

enabling the first receiver region to measure the reflection of the transmitted ultrasonic signal during the first window beginning at the first window begin time comprises controlling an application of a sample voltage to a receiver bias electrode corresponding to the first receiver region during a first range gate window beginning at the first window begin time, and

enabling the second receiver region to measure the reflection of the transmitted ultrasonic signal during the second window beginning at the second window begin time comprises controlling the application of the sample voltage to a receiver bias electrode corresponding to the second receiver region during a second range gate window beginning at the second window begin time.

20. A mobile device comprising:

means for transmitting an ultrasonic signal toward a platen interface of an ultrasonic sensor along an acoustic path that includes means for introducing an acoustic delay gradient;

means for receiving a reflection of the transmitted ultrasonic signal reflected from the platen interface at a first receiver region of an ultrasonic receiver of the ultrasonic sensor at a first time; and

means for receiving the reflection of the transmitted ultrasonic signal reflected from the platen interface at a second receiver region of the ultrasonic receiver at a second time different from the first time.

21. The mobile device of claim 20, wherein the means for introducing the acoustic delay gradient comprises means for causing the reflection from the platen interface to reach the first receiver region after propagating over a first physical distance and means for causing the reflection from the platen interface to reach the second receiver region after propagating over a second physical distance different from the first physical distance.

22. The mobile device of claim 21, wherein the means for introducing the acoustic delay gradient comprises a tapered acoustic delay gradient layer.

23. The mobile device of claim 20, wherein the means for introducing the acoustic delay gradient comprises a means for causing the ultrasonic signal to travel at a first speed of sound along the acoustic path to the first receiver region and a means for causing the ultrasonic signal to travel at a second speed of sound different from the first speed of sound along the acoustic path to the second receiver region.

24. The mobile device of claim 23, wherein

the means for causing the ultrasonic signal to travel at the first speed of sound along the acoustic path to the first receiver region comprises a first acoustic delay gradient layer region comprising a first material;

and

the means for causing the ultrasonic signal to travel at a second speed of sound along the acoustic path to the second receiver region comprises a second acoustic delay gradient layer region comprising a second material different from the first material.

25. The mobile device of claim 20, wherein the means for introducing the acoustic delay gradient is disposed between an ultrasonic transmitter and the ultrasonic receiver.

26. The mobile device of claim 20, wherein the means for transmitting the ultrasonic signal comprises a non-segmented transmitter configured to transmit the ultrasonic signal towards the platen interface across an entirety of the non-segmented transmitter simultaneously.

27. The mobile device of claim 20, wherein

the means for receiving the reflection of the transmitted ultrasonic signal at the first receiver region at the first time comprises means for enabling the first region to measure the reflection of the ultrasonic signal during a first window beginning at a first window begin time;

and

the means for receiving the reflection of the transmitted ultrasonic signal at the second receiver region at the second time comprises means for enabling the second region to measure the reflection of the ultrasonic signal during a second window beginning at a second window begin time, different from the first window begin time.

28. A non-transitory computer readable medium storing instructions for execution by one or more processors of a mobile device to perform operations comprising:

controlling an ultrasonic transmitter of an ultrasonic sensor to transmit an ultrasonic signal toward a platen interface of the ultrasonic sensor along an acoustic path that includes an acoustic delay gradient layer;

enabling a first region of an ultrasonic receiver of the ultrasonic sensor to measure a reflection of the transmitted ultrasonic signal during a first window beginning at a first window begin time; and

enabling a second region of the ultrasonic receiver of the ultrasonic sensor to measure the reflection of the transmitted ultrasonic signal during a second window beginning at a second window begin time different from the first window begin time.

29. The non-transitory computer readable medium of claim 28, wherein

the operations comprising enabling the first region of the ultrasonic receiver of the ultrasonic sensor to measure the reflection of the transmitted ultrasonic signal during the first window beginning at the first window begin time comprises controlling the application of a sample voltage to a receiver bias electrode corresponding to the first receiver region during the first window, and

the operations comprising enabling the second region of the ultrasonic receiver of the ultrasonic sensor to measure the reflection of the transmitted ultrasonic signal during the second window beginning at the second window begin time comprises controlling the application of the sample voltage to a receiver bias electrode corresponding to the second receiver region during the second window.

30. The non-transitory computer readable medium of claim 28 wherein the operations comprising instructing an ultrasonic transmitter of an ultrasonic sensor to transmit an ultrasonic signal comprises instructing a non-segmented transmitter to transmit the ultrasonic signal across an entirety of the non-segmented transmitter simultaneously.