Interferometer delay line with an optical payload supported by

Abstract

An interferometer delay line includes an optical payload displaced along a guide track under the control of a control device including at least one sensing device which senses the position of the payload along the guide track and a drive device acting on the payload. The sensing device includes a linear succession of fixed optical read heads parallel to the guide track and a graduated rule carried by the optical payload in any position on the latter facing at least one of the optical read heads. The sensing device also includes a synchronizing/switching unit causing a counter to count pulses from the heads in succession, the pulses representing distance increments.