The electron cyclotron emission imaging system on EAST with continuous large observation area

A 384 channels (24 vertical × 16 radial) Electron Cyclotron Emission Imaging (ECEI) system has been installed on Experimental Advanced Superconducting Tokamak (EAST). With the aid of advanced front optics, high spaital resolution around 1.1cm and flexible vertical coverage 30∼70 cm have been realized. The well-designed optics also provides a long Rayleigh length up to 70 cm even with an object length larger than 2.6 m. The electronic system has a wide immediate frequency (IF) bandwidth 2∼16.5 GHz, which enables a continuous radial coverage up to 25 cm. Benefited from advanced optics design and the wide IF bandwidth, the ECEI system with high spatial resolution can provide a large and continuous view field, especially in the radial direction, which is enough for the observation of the whole q=1 surface. The comprehensive details of the ECEI system will be presented in this paper, along with some experimental results.