A system for high-frequency recording of plasma diagnostics has previously been reported. Substantial improvements have been made in the system response, dynamic range, and calibration of the system. Plastic-clad silica fiber is used as a radiation-to-light converter using the Cerenkov process. A spectral equalizer device is used to compensate for the material dispersion in the fiber, increasing the frequency response (,1 GHz-km) and the dynamic range (a factor of >20 over a FWHM 1 nm, 50% transmitting interference filter). The calibration system uses a pulsed injection laser diode (<100 ps FWHM) injected into the fiber at the radiation end of the fiber and detected by a microchannel plate photomultiplier tube on the recording end. The injection laser diode is triggered by a synchronous trigger delay unit, which also triggers a sampling or real time scope after as much as 10 μs delay with <50 ps jitter. The system improvements will be desribed in more detail and the utility of these components in other plasma diagnostic systems will be discussed.

Date Published: 22 January 1982
PDF: 6 pages
Proc. SPIE 0296, Fiber Optics in Adverse Environments I, (22 January 1982); doi: 10.1117/12.932445

Published in SPIE Proceedings Vol. 0296:
Fiber Optics in Adverse Environments I
Peter B. Lyons, Editor(s)