Device having embedded antenna

1. A body-mountable device comprising:

a transparent polymer, wherein the transparent polymer defines a posterior side and an anterior side of the body-mountable device; and

a structure embedded in the transparent polymer, wherein the structure has an outer circumference defined by an outer diameter and an inner circumference defined by an inner diameter and includes a sensor configured to detect an analyte, electronics, and an antenna, wherein the antenna includes a plurality of conductive loops spaced apart from each other between the outer circumference and the inner circumference, wherein, with respect to a vertical axis between the anterior side of the body-mountable device and the posterior side of the body-mountable device, a particular conductive loop in the plurality of conductive loops is spaced vertically apart and horizontally apart from an adjacent conductive loop in the plurality of conductive loops,

wherein each conductive loop in the plurality of conductive loops comprises a respective metal layer disposed between a first respective polymer layer and a second respective polymer layer, and wherein the respective metal layer, the first respective polymer layer, and the second respective polymer layer are each embedded in the transparent polymer,

wherein the transparent polymer extends from the anterior side of the body-mountable device to the posterior side of the body-mountable device between adjacent conductive loops in the plurality of conductive loops, and

wherein each conductive loop in the plurality of conductive loops is connected to a first interconnect and a second interconnect, wherein the electronics and sensor are disposed between the first and second interconnects, and wherein each conductive loop in the plurality of conductive loops is electrically connected to the electronics and sensor via the first and second interconnects.

2. The body-mountable device of claim 1 , wherein the body-mountable device comprises an eye-mountable device.

3. The body-mountable device of claim 1 , wherein the body-mountable device comprises a tooth-mountable device.

4. The body-mountable device of claim 1 , wherein the body-mountable device comprises a skin-mountable device.

5. The body-mountable device of claim 1 , wherein the conductive loops are substantially concentric.

6. The body-mountable device of claim 1 , wherein the plurality of conductive loops comprises at least three conductive loops.

7. The body-mountable device of claim 1 , wherein the metal and first and second polymer layers in each conductive loop are spaced apart from the metal and first and second polymer layers in each adjacent conductive loop in the plurality of conductive loops.

8. The body-mountable device of claim 7 , wherein the metal and first and second polymer layers of a particular conductive loop in the plurality of conductive loops are spaced apart from the metal and first and second polymer layers of a first adjacent conductive loop in the plurality of conductive loops by a first distance, and wherein the metal and first and second polymer layers of the particular conductive loop are spaced apart from the metal and first and second polymer layers of a second adjacent conductive loop in the plurality of conductive loops by a second distance.

9. The body-mountable device of claim 8 , wherein the first distance varies based on a rotational orientation of the particular conductive loop relative to the first adjacent conductive loop.

10. The body-mountable device of claim 8 , wherein the second distance varies based on a rotational orientation of the particular conductive loop relative to the second adjacent conductive loop.

11. The body-mountable device of claim 7 , wherein the first and second polymer layers in each conductive loop comprise paralyene.

12. The body-mountable device of claim 1 , further comprising one or more spacers configured to maintain substantially uniform spacings between adjacent conductive loops in the plurality of conductive loops.

13. The body-mountable device of claim 12 , wherein the one or more spacers comprise a polymeric material.

14. The body-mountable device of claim 12 , wherein the one or more spacers comprise a metal.

15. The body-mountable device of claim 12 , wherein the one or more spacers comprise one spacer positioned on the structure substantially opposite of the sensor.

16. The body-mountable device of claim 12 , wherein the one or more spacers are positioned on the structure at a predetermined rotational orientation.