BigMIC is a large area image photon counting system that has been designed for applications in astronomy requiring the highest sensitivity and resolution such as echelle spectroscopy with very large telescopes. It consists of a 75 mm diameter image intensifier fibre-optically coupled to a fast scanning 770x576 pixel frame-transfer CCD camera. The system was built in collaboration with the Imperial College of Science, Technology and Medicine who were in charge of the intensifiers development. My responsibility was to design and construct the high-speed CCD camera and processing electronics necessary to obtain high resolution. The image intensifier has, inherently, a resolution loss associated. Real time centroiding, on the photon event scintillations produced by the intensifier and captured by the CCD camera, is utilised to minimise this resolution loss. I also had the responsibility for comparing different centroiding algorithms and their effect on system performance. Programmes that simulated the detector system were written for the algorithm comparison and were additionally used for assessing potential upgrades to the system. In this thesis a complete description of the BigMIC system is given and a comparison with other photon counting systems, currently used for astronomical applications, is made. The electronic design of the CCD camera and processing electronics is fully explained with the inclusion of schematic diagrams. A chapter is dedicated to microchannel plate image intensifiers with the inclusion of a study of the properties of photocathode and phosphor screen materials. The computer simulations are also presented in detail with the results and their effect on the hardware design of the system. The thesis is concluded with a study of the final performance of the system and a series of recommendations for improvements in future designs are given.
展开▼
