EFFECT OF LASER SOURCE NONLINEARITY ON OPTICAL HETERODYNE INTERFEROMETRY

In this paper, an optical heterodyne interferometric detection model w ith a frequency-ramped laser diode ( LD) has been analyzed. The effect of the nonlinearity of the LD source on the optical heterodyne interf erometry has been investigated in two different ways, which are the po wer-distortion Fourier series analysis and the harmonic distortion ana lysis. The general formulation between the tangent of the tested phase and the interference fringe have been presented with the analysis of the beat signal in the frequency domain by each methodology. The numer ical results of these formulations have been presented.