Fiber-optic michelson interferometer sensor fabricated by femtosecond lasers

The femtosecond laser is widely applied in all kinds of laser micro machining technology with its short pulse duration, high peak power, high machining accuracy and low damage threshold. A fiber optic Michelson interferometer cavity is presented by using femtosecond laser micromachining technology. The cavity has good shape of interference fringes and high contrast which is up to 15 dB. A demodulation algorithm is proposed to calculate the cavity length with high resolution. The temperature experiment shows that the interferometer cavity has sensitivity of 0.00428 μm/°C with good linearity. In addition, the micro fiber Michelson sensor is resistant to high temperature and great potential for application in harsh environments. © 2013 IFSA.