Low-cost wavemeter with a solid Fizeau interferometer and fiber-optic input.

A wavemeter suitable for measuring the wavelength of pulsed and continuous laser light has been constructed on the basis of a solid Fizeau interferometer (SFI). An accuracy of 1 part in 10(6) has been demonstrated in a range extending from 563 to 613 nm. The use of the SFI and of a combination of a single-mode optical fiber and an achromatic lens as a beam collimating system substantially simplifies the optical layout and reduces cost. The difficulties connected with the dispersion of the SFI have been overcome by an analytical description of the characteristics of the interferometer and accurate temperature stabilization.