| Popis: |
The surroundings of a nuclear fusion reactor experiments the presence of magnetic fields, which affects the performance of any diagnostic optical system located nearby. It is therefore necessary to determine with precision the optimum location for the diagnostic and to design magnetically robust optical imaging systems. The purpose of the present optical diagnostic is to measure the temperature dispersion in the vicinity of the NBI (neutral beam injectors) that heat the confined plasma inside the fusion device. The measure is made by processing the information contained in the images of the objects inside the chamber in the 7 to 16 um far infrared wavelength range, through a F2Ba vacuum viewport window. Our main concern is to design the optical relay from this viewport to the IR sensor, a FPA uncooled microbolometer 320x240px, for different axial distances, with a field of view of 24°x18° and 1.3 mrad of IFOV spatial resolution. The proposed optical relay system includes the use of a reflexive relay (aspheric concave mirrors) and a refractive and imaging camera. The system has being corrected for primary aberrations and optimized to allow a future second optical system working in visible range after the mirrors, by including a dichroic beamsplitter. |
