| 摘要 |
A method of investigating a sample 7, the method comprising the steps of: (a) irradiating a sample with a beam of pulsed radiation 4 comprising a plurality of frequencies; (b) measuring the beam 5 reflected by (or transmitted through) the sample and obtaining a signal representative of the measured beam; (c) multiplying the signal of step (b) in the frequency domain by the complex Fourier transform of F(t), where F(t) is a non-zero function whose integral between limits t1 and t2 is zero, where t1 and t2 are chosen on the basis of the time delay introduced by the sample. |
