Ultrasonic fingerprint sensor for under-display applications

Patent metadata

Field	Value
Publication number	US-12327426-B2
Application number	US-202318103060-A
Country	US
Kind code	B2
Filing date	Jan 30, 2023
Priority date	Jun 26, 2017
Publication date	Jun 10, 2025
Grant date	Jun 10, 2025

Abstract

Disclosed are methods, devices, apparatuses, and systems for an under-display ultrasonic fingerprint sensor. A display device may include a platen, a display underlying the platen, and an ultrasonic fingerprint sensor underlying the display, where the ultrasonic fingerprint sensor is configured to transmit and receive ultrasonic waves via an acoustic path through the platen and the display. A light-blocking layer and/or an electrical shielding layer may be provided between the ultrasonic fingerprint sensor and the display, where the light-blocking layer and/or the electrical shielding layer are in the acoustic path. A mechanical stress isolation layer may be provided between the ultrasonic fingerprint sensor and the display, where the mechanical stress isolation layer is in the acoustic path.

First claim

What is claimed is:

1. An apparatus comprising:
a display;
an ultrasonic sensor system underlying the display and configured to transmit and receiving ultrasonic waves in an acoustic path through the display;
an electrical shielding layer between the ultrasonic sensor system and the display; and
a light-blocking layer between the display and the electrical shielding layer, wherein the light-blocking layer comprises an opaque plastic material, wherein each of the electrical shielding layer and the light-blocking layer is non-porous or substantially non-porous.

2. The apparatus of claim 1 , wherein the electrical shielding layer is electrically conductive and grounded, the electrical shielding layer positioned in the acoustic path.

3. The apparatus of claim 2 , wherein the electrical shielding layer includes a metal or metalized plastic having a thickness between about 0.1 μm and about 9 μm.

4. The apparatus of claim 1 , wherein the display is an organic light-emitting diode (OLED) display.

5. The apparatus of claim 4 , wherein the display is a flexible OLED display formed on a plastic substrate.

6. The apparatus of claim 1 , further comprising:
an adhesive layer between the ultrasonic sensor system and the display, wherein the adhesive layer includes a pressure-sensitive adhesive.

7. The apparatus of claim 1 , further comprising:
an adhesive layer between the ultrasonic sensor system and the display, wherein the adhesive layer includes an epoxy-based adhesive, the epoxy-based adhesive including a thermoplastic ink.

8. The apparatus of claim 1 , further comprising:
a mechanical stress isolation layer between the ultrasonic sensor system and the display, wherein the mechanical stress isolation layer resides between the adhesive layer and the ultrasonic sensor system and includes a plastic material.

9. The apparatus of claim 1 , wherein the ultrasonic sensor system includes:
a sensor substrate having a plurality of sensor pixel circuits disposed thereon;
a piezoelectric transceiver layer coupled to the sensor substrate and including a piezoelectric material configured to generate the ultrasonic waves; and
the electrode layer coupled to the piezoelectric transceiver layer.

10. The apparatus of claim 9 , wherein the piezoelectric transceiver layer is underlying the sensor substrate and the electrode layer is underlying the piezoelectric transceiver layer.

11. The apparatus of claim 9 , wherein the piezoelectric transceiver layer is underlying the electrode layer and the sensor substrate is underlying the piezoelectric transceiver layer.

12. The apparatus of claim 9 , wherein the piezoelectric transceiver layer includes polyvinylidene fluoride (PVDF), polyvinylidene fluoride trifluoroethylene (PVDF-TrFE) copolymer, lead zirconate titanate (PZT), aluminum nitride (AlN), or composites thereof.

13. The apparatus of claim 9 , wherein the sensor substrate comprises a material selected from the group consisting of: glass, plastic, silicon, and stainless steel.

Assignees

• Qualcomm Inc

Inventors

• Panchawagh Hrishikesh Vijaykumar
• Badge Ila Ravindra
• Lu Yipeng
• Djordjev Kostadin Dimitrov
• Ganti Suryaprakash
• Tseng Chin-Jen
• Buchan Nicholas Ian
• Kao Tsongming
• Fennell Leonard Eugene
• Sammoura Firas
• Strohmann Jessica Liu
• Burns David William

Classifications

• H10K59/00

  Integrated devices, or assemblies of multiple devices, comprising at least one organic light-emitting element covered by group H10K50/00 · CPC title

• H10K59/8792

  comprising light absorbing layers, e.g. black layers · CPC title

• H10K59/8722

  Peripheral sealing arrangements, e.g. adhesives, sealants · CPC title

• H10K2102/311

  Flexible OLED · CPC title

• H10K77/111

  Flexible substrates · CPC title