Input Optics R&D Activities

Overview

The University of Florida and their collaborators made progress on the challenges in the Input Optics subsystem. A novel Faraday Isolator design was developed which uses a pair of crystals in a compensation technique to deliver high isolation at high powers. In this design shown in Figure 1, two 22.5° Faraday rotators and a reciprocal quartz polarization rotator placed between them replace the traditional single crystal 45° Faraday rotator. In such a configuration, polarization distortions that a beam experiences while passing the first rotator will be compensated in the second. Tests to the maximum power available are encouraging.

Figure 1 Top: compensated Faraday isolator design. Bottom: isolation for a conventional and the compensated design.

We favorably reviewed the Input Optics Design Requirements prepared by the group at the University of Florida, and the group was given approval to proceed to the preliminary design.