Image analysis and data‐acquisition techniques for infrared and CCD cameras for ATF

A multipurpose image processing system has been developed for the Advanced Toroidal Facility (ATF) stellarator experiment. This system makes it possible to investigate the complicated topology inherent in stellarator plasmas with conventional video technology. Infrared (IR) and charge‐coupled device (CCD) cameras, operated at the standard video framing rate, are used on ATF to measure heat flux patterns to the vacuum vessel wall and visible‐light emission from the ionized plasma. These video cameras are coupled with fast acquisition and display systems, developed for a MicroVAX‐II, which allow between‐shot observation of the dynamic temperature and spatial extent of the plasma generated by ATF. The IR camera system provides acquisition of one frame of 60×80 eight‐bit pixels every 16.7 ms via storage in a CAMAC module. The CCD data acquisition proceeds automatically, storing the video frames until its 12‐bit, 1‐Mbyte CAMAC memory is filled. After analysis, transformation, and compression, selected portions of the data are stored on disk. Interactive display of experimental data and theoretical calculations are performed with software written in Interactive Data Language.