RF proximity sensor

摘要

A sensor has a strip resonator filter that energizes an emitter patch which emits an electric field out from the strip resonator filter (away from the strip resonator filter). The capacitance of the filter, or specifically the coupling capacitance and radiation pattern of the slotted patch, is altered when an object such as a finger is near the sensor. Resulting changes in a signal outputted by the filter can be used to determine how close the object is to the sensor. The strip resonator filter may be a half wavelength strip resonator coupled filter having three separate strips. The patch may have a slot and two accompanying strips. An arrangement of multiple sensors may detect the position of an object in two or three dimensions.

主权项

1. A sensor comprising:
a first substrate layer; a second substrate layer; a half wavelength strip resonator between the first substrate layer and the second substrate layer; and a conductive patch and a pair of parasitic strips, the patch and the parasitic strips separated from the half wavelength strip resonator by the second substrate layer, wherein the strips are arranged such that the patch is between the parasitic strips, wherein the conductive patch comprises a conductive island that is not conductively connected with any other conductor of the sensor.