Double-frequency laser interferometer with unambiguous phase reading for large tokamaks
| Autor: | V. G. Petrov, V. F. Shevchenko, A. A. Petrov |
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| Rok vydání: | 1999 |
| Předmět: | |
| Zdroj: | Plasma Devices and Operations. 7:103-110 |
| ISSN: | 1029-4929 1051-9998 |
| DOI: | 10.1080/10519999908224462 |
| Popis: | The proportional phase conversion of a measured interferometrie phase shift on the intermediate frcquency using double-freauency plasma probing is proposcd in order to overcome problems encountered in the course of interferometer measurements under high-density regimes in tokamaks (fringe “jumps” due to high density rise rate, large phase shifts to be measured, etc). The method is based upon an opportunity of multi-frequency lasing (e.g., DCN laser). Basic scheme of such an interferometer is described. Estimations of influence of the frequency stability or radiation sources and signal-to-noise ratio on the aceuracy of phase measurements are given. Relative simplicity of the optical circuit allows easily to extend the technique to apply it for multichord measurements of the plasma density and for measurements of Faraday rotation angle. Double-frequency laser interferometer with an unambiguous phase reading can be used as a line integral density monitor on the ITER facility, especially for a densit... |
| Databáze: | OpenAIRE |
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