Micro-tip Cantilever as Low Frequency Microphone.

We propose a very compact diaphragm free optical microphone consisting a tapered micro-tip in cantilever configuration for detection of low frequency acoustic signals. The change in the light coupling between the micro-tip and the source fiber caused by the acoustic pressure is utilized to detect the external acoustic signal. The sensitivity and working range of the sensor depend on three key factors, the length of the micro-tip cantilever, the distance between the micro-tip and SMF, and the offset between the micro-tip central axis and SMF central axis.

Nano-displacement sensor based on photonic crystal fiber modal interferometer.

A stable nano-displacement sensor based on large mode area photonic crystal fiber (PCF) modal interferometer is presented. The compact setup requires simple splicing of a small piece of PCF with a single mode fiber (SMF). The excitation and recombination of modes is carried out in a single splice.