Optical vibrating quartz crystal pressure sensor using frustrated-total-internal-reflection readout technique

An optically driven, through photovoltaic conversion, pressure sensor is described which uses frustrated-total-internal-reflection between a critically cut optical fiber and a quartz crystal, mounted on a cantilever beam to sense the device resonant frequency. The change in this frequency as a function of applied pressure is measured in this sensor which relies upon an all-optical link to the control electronics.