Absolute distance measurement using individual frequency modes of the electro-optic comb based on multi-wavelength interferometry

Multi-wavelength interferometer is one of the most widely used methods for measuring absolute distances with high precision, which typically uses more than three frequency-stabilized lasers to solve the phase ambiguity problem. However, despite its high measurement precision, it is practically not easy to install and maintain several frequency-stabilized lasers. In this work, we proposed and realized a multi-wavelength interferometer using an electro-optic comb with a wide frequency mode spacing, which is enough to consider each frequency mode as a single laser. Absolute distance was measured using the proposed method, and measurement uncertainty was estimated for performance evaluation.