To demonstrate the principle for detecting a phase of equidistant and straight fringes, experimental results for measuring a displacement of a piezoelectric transducer device using a new polarizing Michelson interferometer are presented. A simple birefringent wedge of a uniaxial crystal is used to form an equidistant and straight fringe pattern. The shift of the fringe pattern is calculated from an arctangent of Fourier cosine and sine integrals of the fringe intensity. The minimum detectable phase change is approximately a 470th of the wavelength of the laser light, including external disturbances in the interferometer. Applications of the phase detection include use in highly sensitive optical sensors for pressure and temperature.
© 1988 Optical Society of America
Suezou Nakadate, "Phase detection of equidistant fringes for highly sensitive optical sensing. II. Experiments," J. Opt. Soc. Am. A 5, 1265-1269 (1988)