Optical-frequency scanning-rate calibration of external cavity diode lasers using adaptive complex-shifted Morlet wavelets

Abstract

Real-time measurement of the optical frequency of an external cavity diode laser (ECDL) is very difficult. In this study, a novel adaptive complex-shifted Morlet wavelets method was proposed to accurately determine the instantaneous frequency of the interference signal. The optical frequency scanning rate and the change in the optical frequency trend could then be obtained using the instantaneous frequency. The proposed method was theoretically analyzed, and both simulations and experimental results confirm that the method can accurately obtain the scanning rate and change in the trend of the ECDL optical frequency. The experimental results demonstrate that the maximum single-cycle relative error was less than 2.5‰ and the linearity of output optical frequency with correction was good and R2 was 0.999 98.

Enhancement of frequency scanning interferometry signal for non-cooperative target based on generative adversarial network

“…Finally, two FSI algorithms, namely, Morlet wavelet demodulation [3] and in-phase quadrature demodulation [21], were used validate the measurement results for the noncooperative targets at six different locations.…”

“…As a high-precision and low-cost absolute distance optical measurement method, frequency scanning interferometry (FSI) is widely used in absolute distance measurement [1][2][3][4][5][6][7][8], geometric accuracy monitoring of large machining centres [9], optical fibre non-destructive testing [10,11], optical coherence tomography [12,13], and light detection and ranging for autonomous driving, as well as other fields [14,15]. In FSI measurement, to obtain high-precision measurement results, a cooperative target mirror is typically used as the point to be measured.…”