| 摘要 |
Method and device for optical inspection of a sample using spectral interferometry, wherein a beam (2'') emitted by a radiation source (1) is directed onto the sample (5) and a reference beam (2') is directed onto a reference sample (4), and the spectral interference of both beams after being reflected on the samples or after passing the samples is recorded by means of a spectrograph (6); the interferogram I (omega) thus obtained is numerically derived with respect to the angular frequency omega. For the function I ` (omega) thus obtained the zeros omegai are calculated numerically as solutions to the equation I ` (omega) = 0 and the frequency-dependent group delay tau (omega) is then calculated from the zeros omegai according to the equation tau (omegan) = pi / (omegai+1-omegai), wherein i = 1, 2... and omegan = (omegai+1 + omegai) /2. |
