Measurements with a Fourier Transform Wavemeter

In this paper we describe the results of wavelength comparisons of lasers done with a Fourier Transform (FT) spectrometer in the visible and near infrared region. The spectrometer employs the Fast Fourier Transformation (FFT) routine to determine absolute wavelengths and mode structures of mono- and multi-mode lasers relative to a stabilized He-Ne (633 nm) laser.