Search

Spatial distribution of optical phase and amplitude can be measured by using a single-mode optical-fiber interferometric system. Following the first proposal of the measuring principle by the present authors in 1978, a further development of the measuring system is now reported. The major achievement is the use of a novel spatial filter and a set of photodetectors by which the interference fringe position is located. Combining them with analog signal-processing circuitry and with a mechanical feedback system, fully automated recording of the optical phase and amplitude distribution is successfully achieved. The method is used to measure phase-front distribution near a Gaussian beam waist.

Features the development of superconducting field effect transistors at Sumitomo Electric Industries Ltd. Oxide superconductor; UHV system; Co-evaporation; STO/YBCO bilayer.