Electronic device with near-field antenna operating through display
An electronic device may have a display. A display cover layer and a transparent inner display member may overlap a display pixel layer. The display pixel layer may have an array of display pixels for displaying images for a user. A touch sensor layer may be interposed between the display pixel layer and the transparent display member. A ferromagnetic shielding layer may be mounted below the display pixel layer. A flexible printed circuit containing coils of metal signal lines that form a near-field communications loop antenna may be interposed between the ferromagnetic shielding layer and the display pixel layer. A non-near-field antenna such as an inverted-F antenna may have a resonating element mounted on an inner surface of the display cover layer. The resonating element may be interposed between the transparent display member and the display cover layer.
1. An electronic device comprising:
a housing;
a curved cover layer for a display coupled to the housing;
a display pixel layer for the display that is overlapped by the curved cover layer at an active area of the display;
an antenna resonating element for an antenna that is overlapped by the curved cover layer at an inactive area of the display; and
a biasing structure configured to press the antenna resonating element toward the curved cover layer at the inactive area of the display, wherein the antenna resonating element is disposed on a dielectric substrate and the biasing structure is configured to press the antenna resonating element toward the curved cover layer at the inactive area of the display by applying a force to the dielectric substrate in a direction toward the curved cover layer.
2. The electronic device defined in claim 1 , wherein the antenna resonating element comprises conductive traces on the dielectric substrate.
3. The electronic device defined in claim 2 , wherein the dielectric substrate is a flexible printed circuit substrate.
4. The electronic device defined in claim 1 , wherein the antenna comprises a first antenna feed terminal on the antenna resonating element and a second antenna feed terminal coupled to an antenna ground for the antenna.
5. The electronic device defined in claim 4 , wherein the antenna resonating element comprises an antenna resonating element arm, and the antenna comprises a return path that couples the antenna resonating element arm to the antenna ground.
6. The electronic device defined in claim 5 , wherein the dielectric substrate comprises a flexible printed circuit substrate, and the antenna resonating element arm, the return path, and ground conductive traces are formed on the flexible printed circuit substrate.
7. The electronic device defined in claim 6 , wherein the antenna ground comprises a portion of the housing and the ground conductive traces.
8. The electronic device defined in claim 1 , wherein the curved cover layer has a curved outer surface and an inner surface opposite the curved outer surface, and the biasing structure is configured to press the antenna resonating element against the inner surface of the curved cover layer.
9. The electronic device defined in claim 8 , wherein the inner surface is a curved inner surface.
10. The electronic device defined in claim 8 further comprising:
opaque material between the curved outer surface and the antenna resonating element.
11. The electronic device defined in claim 1 , wherein the biasing structure comprises compressible material.
12. The electronic device defined in claim 1 , wherein the biasing structure comprises a compressible foam structure.
13. The electronic device defined in claim 1 further comprising:
a strap attached to the housing.
14. The electronic device defined in claim 1 , wherein the biasing structure is mounted to the housing.
15. An electronic device comprising:
a curved display cover layer;
a display pixel layer that overlaps the curved display cover layer;
a flexible printed circuit that includes a substrate and conductive traces on the substrate, the conductive traces forming an antenna resonating element configured to convey radio-frequency signals through the curved display cover layer; and
a biasing structure configured to apply a force toward the curved display cover layer that presses the flexible printed circuit toward the curved display cover layer.
16. The electronic device defined in claim 15 further comprising:
a housing, wherein the biasing structure is mounted between the housing and the flexible printed circuit.
17. The electronic device defined in claim 15 , wherein the biasing structure comprises foam.
18. The electronic device defined in claim 15 , wherein the conductive traces form an antenna ground and a return path that is coupled between the antenna resonating element and the antenna ground.
19. An electronic device comprising:
a housing;
a curved cover layer for a display coupled to the housing;
a display pixel layer for the display that is overlapped by the curved cover layer at an active area of the display;
an antenna resonating element for an antenna that is overlapped by the curved cover layer at an inactive area of the display; and
a biasing structure configured to apply a force toward the curved cover layer that presses the antenna resonating element toward the curved cover layer at the inactive area of the display.
20. The electronic device defined in claim 19 , wherein the antenna resonating element is pressed against an inner surface of the curved cover layer.