Electronic Device With Fingerprint Sensor and Tunable Hybrid Antenna

• US 20160056527A1
• Filed: 08/19/2014
• Published: 02/25/2016
• Est. Priority Date: 08/19/2014
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Pascolini, Mattia, Jin, Nanbo
• Granted Patent: US 9,577,318 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: G06F 21/32 using biometric data, e.g. fingerprints, iris scans or voiceprints
• CPC Class Codes: G06V 40/12 Fingerprints or palmprints
• CPC Class Codes: G06V 40/1306 non-optical, e.g. ultrasonic or capacitive sensing
• CPC Class Codes: H01Q 1/2258 used with computer equipment
• CPC Class Codes: H01Q 1/243 with built-in antennas
• CPC Class Codes: H01Q 1/38 formed by a conductive layer on an insulating support patch antennas H01Q9/0407; microstrip dipole antennas H01Q9/065; microstrip slot antennas H01Q13/106; transmission line microstrip antennas H01Q13/206; manufacturing reflecting surfaces using insulating material for supporting the reflecting surface H01Q15/142
• CPC Class Codes: H01Q 1/48 Earthing means; Earth screens; Counterpoises
• CPC Class Codes: H01Q 13/10 Resonant slot antennas
• CPC Class Codes: H01Q 13/103 with variable reactance for tuning the antenna tuning resonant circuits H03J
• CPC Class Codes: H01Q 3/247 by switching different parts of a primary active element
• CPC Class Codes: H01Q 9/0421 with a shorting wall or a shorting pin at one end of the element H01Q9/0414 takes precedence
• CPC Class Codes: H01Q 9/0485 Dielectric resonator antennas
• CPC Class Codes: H01Q 9/42 with folded element, the folded parts being spaced apart a small fraction of the operating wavelength
• CPC Class Codes: H04M 1/026 Details of the structure or mounting of specific components
• CPC Class Codes: H04N 23/54 Mounting of pick-up tubes, electronic image sensors, deviation or focusing coils

Abstract

An electronic device may have wireless circuitry and components such as sensors. The electronic device may have a metal housing having first and second planar rear wall portions separated by a gap. Conductive structures may bridge the gap to electrically couple the first and second rear wall portions. The wireless circuitry may include a hybrid slot inverted-F antenna. The antenna may have an inverted-F antenna resonating element formed from peripheral housing structures that are separated from the second rear wall portion by an opening. The opening may form a C-shaped slot antenna resonating element for the antenna. The sensors may include a fingerprint sensor. The fingerprint sensor may be coupled to a button member in a button. The fingerprint sensor and other portions of the button may overlap the second planar rear wall portion to minimize interference with antenna operation.

Claims

1. An electronic device, comprising:

a housing having peripheral conductive structures; and

a hybrid inverted-F slot antenna, wherein the hybrid inverted-F slot antenna has an inverted-F antenna portion formed from an inverted-F antenna resonating element and an antenna ground, wherein the inverted-F antenna resonating element is formed from the peripheral conductive structures, wherein the hybrid inverted-F slot antenna has a slot antenna portion formed from an opening between the inverted-F antenna resonating element and the antenna ground, and wherein the antenna ground has an extended portion adjacent to the slot;

an antenna feed that feeds both the inverted-F antenna portion and the slot antenna portion,; and

a fingerprint sensor overlapping the extended portion of the antenna ground.

2. The electronic device defined in claim 1 further comprising a flexible printed circuit, wherein the fingerprint sensor is mounted to the flexible printed circuit and wherein a portion of the flexible printed circuit on which the fingerprint sensor is mounted overlaps the extended portion of the antenna ground.

3. The electronic device defined in claim 2 wherein the housing has a metal rear wall and wherein the antenna ground is formed from the metal rear wall.

4. The electronic device defined in claim 3 wherein the extended portion of the antenna ground is formed from the metal rear wall.

5. The electronic device defined in claim 4 further comprising:

a button that has a switch.

6. The electronic device defined in claim 5 wherein the button overlaps the extended portion of the antenna ground.

7. The electronic device defined in claim 6 wherein the fingerprint sensor is mounted within the button.

8. The electronic device defined in claim 7 wherein the metal rear wall has a first planar portion and a second planar portion that are separated by a gap filled with plastic and that are electrically coupled by conductive structures, wherein the first portion forms at least part of the antenna ground, and wherein the second portion forms the extended portion of the antenna ground.

9. The electronic device defined in claim 8 further comprising:

a connector receptacle, wherein the button overlaps the connector receptacle.

10. The electronic device defined in claim 9 wherein the opening is a C-shaped slot having a portion that runs along the peripheral conductive structures.

11. The electronic device defined in claim 10 further comprising:

a display having a display module that overlaps the antenna ground without overlapping the extended portion of the antenna ground and having a display cover layer that overlaps the display module and the extended portion of the antenna ground.

12. The electronic device defined in claim 1 wherein the slot is a C-shaped slot that runs along peripheral edges of the housing and wherein the antenna feed has first and second feed terminals on opposing sides of the C-shaped slot.

13. The electronic device defined in claim 12 further comprising:

an inductor and a switch that are connected in series and that are coupled to the hybrid inverted-F slot antenna, wherein the switch is configured to switch the inductor into use and out of use to compensate for detuning of the antenna due to presence of an external object adjacent to the hybrid inverted-F slot antenna.

14. An electronic device comprising:

a metal housing have a rear wall with a first rear wall portion and a second rear wall portion separated by a dielectric-filled gap;

conductive structures that bridge the gap and electrically couple the first rear wall portion to the second rear wall portion; and

a fingerprint sensor that overlaps that second rear wall portion.

15. The electronic device defined in claim 14 further comprising:

an antenna, wherein the rear wall forms an antenna ground for the antenna and wherein the antenna ground has an extended ground portion formed from the second rear wall portion.

16. The electronic device defined in claim 15 wherein the antenna comprises a slot antenna resonating element formed from an opening between the extended ground portion and peripheral conductive structures in the metal housing.

17. The electronic device defined in claim 16 wherein the opening is a C-shaped slot.

18. The electronic device defined in claim 17 further comprising:

a feed terminal coupled to the peripheral conductive structures, wherein the peripheral conductive structures form an inverted-F antenna resonating element in the antenna, wherein an adjustable inductor for tuning a communications band for the antenna is coupled between the peripheral conductive structures and extended ground portion; and

a switch and inductor that are coupled in series and that are coupled to the antenna, wherein the switch is configured to switch the inductor out of use in response to determining that an external object is present adjacent to the antenna.

19. An electronic device, comprising:

a hybrid inverted-F slot antenna having an inverted-F antenna resonating element, a slot antenna resonating element, and an antenna ground; and

a switch and an inductor coupled to the hybrid inverted-F slot antenna, wherein the switch is configured to switch the inductor out of use in response to detecting a user'"'"'s hand adjacent to the antenna.

20. The electronic device defined in claim 19 further comprising a fingerprint sensor that overlaps a portion of the antenna ground.

21. The electronic device defined in claim 20 wherein the slot antenna resonating element is formed from a C-shaped slot that separates the inverted-F antenna resonating element from the portion of the antenna ground.

22. The electronic device defined in claim 21 further comprising an adjustable inductor that is coupled across the slot antenna resonating element and that tunes a low communications band for the hybrid inverted-F slot antenna.