| 摘要 |
<p>The invention features a method including: (i) providing an interference signal S(t) from two beams derived from a common source and directed along different paths, wherein the signal S(t) is indicative of changes in an optical path difference nL(t) between the different paths, where n is an average refractive index along the different paths, L(t) is a total physical path difference between the different paths, and t is time; (ii) providing coefficients representative of one or more errors that cause the signal S(t) to deviate from an ideal expression of the form A<SUB>1 </SUB>cos(omega<SUB>R</SUB>t+phi(t)+zeta<SUB>1</SUB>), where A<SUB>1 </SUB>and zeta<SUB>1 </SUB>are constants, omega<SUB>R </SUB>is an angular frequency difference between the two beams, and phi(t)=nkL(t), with k=2pi/lambda and lambda equal to a wavelength for the beams; (iii) calculating a quadrature signal S(t) based on the signal S(t); and (iv) reducing the deviation of S(t) from the ideal expression using an error signal S<SUB>psi</SUB>(t) generated from the coefficients and error basis functions derived from the signals S(t) and S(t).</p> |
