In the frame of the LEAPS-Innov pilot project, the ESRF together with ALBA, Soleil, PTB and HZB have developed a position measuring system based on fibered laser interferometers and beam steering mirrors that track the position of the object to be measured thanks to a closed loop control system. The global objective is to measure the position of objects moving in a plane along 3 degrees of freedom (2 translations and one rotation), with a typical range of a few millimeters and a few tens of degrees and with a repeatability of 10 nanometers. This system could typically be used for measuring sample position in experimental stations. The project was divided in 2 parts, the first one being dedicated to the characterization of periodic non linearities of commercially available fibered interferometers by all project partners and continued with the design and construction of a 3 axes prototype system at ESRF. I will present the results of the interferometers characterization, the design of the mechanical, optical and control systems used to implement this prototype and the experimental results obtained.
Villar et al. (Thu,) studied this question.