Laser in vessel viewing system for nuclear fusion reactors

L. Bartolini, A. Bordone, A. Coletti, M. Ferri De Collibus, G. Fornetti, S. Lupini, C. Neri, C. Poggi, M. Riva, L. Semeraro, C. Talarico

Research output: Contribution to journalArticle

10 Citations (Scopus)


An amplitude modulated laser radar has been developed by ENEA (Italian Agency for New Technologies, Energy and Environment) for periodic in-vessel inspection in large fusion machines. Its overall optical design has been developed taking into account the extremely high radiation levels and operating temperatures foreseen in large European fusion machines such as JET (Joint European Torus) and ITER (International Thermo-nuclear Experimental Reactor). The viewing system is based on a transceiving optical radar using a RF modulated single mode 840 nm wavelength laser beam. The sounding beam is transmitted through a coherent optical fiber and a focusing optic to the inner part of the nuclear reactor vessel by a stainless steel probe on the tip of which a suitable scanning silica prism steers the laser beam along a linear raster spanning a -90° to +60° in elevation and 360° in azimuth for a complete mapping of the vessel itself. All the electronics, including the laser source, avalanche photodiode and all the active components are located outside the bioshield, while passive components (receiving optics, transmitting collimator, fiber optics), located in the torus hall, are made of fused silica so that the overall laser radar is radiation resistant. The signal is acquired, the raster lines being synchronized with the aid of optical encoders linked to the scanning prism, thus yielding a TV like image. Preliminary results have been obtained scanning large sceneries including several real targets having different backscattering properties, colors and surface reflectivity ranging over several decades to simulate the expected dynamic range of the video signals incoming from the vessel. © 2000 SPIE-The International Society for Optical Engineering.
Original languageEnglish
Pages (from-to)201 - 211
Number of pages11
JournalProceedings of SPIE - The International Society for Optical Engineering
Issue number1
Publication statusPublished - 22 Nov 2000
Externally publishedYes


All Science Journal Classification (ASJC) codes

  • Electronic, Optical and Magnetic Materials
  • Condensed Matter Physics
  • Computer Science Applications
  • Applied Mathematics
  • Electrical and Electronic Engineering

Cite this

Bartolini, L., Bordone, A., Coletti, A., De Collibus, M. F., Fornetti, G., Lupini, S., ... Talarico, C. (2000). Laser in vessel viewing system for nuclear fusion reactors. Proceedings of SPIE - The International Society for Optical Engineering, 4124(1), 201 - 211.