Design of an F/1.0 spectrograph camera: 'Surfing' the 15 dimensional design space of 1 million optical systems

This paper describes a real time optimization method for optical systems. We examine the features of the Global-Opt optical ray tracing program, which has been developed to provide the optical engineer with interactive optimization capabilities. We illustrate the programs main features through the results of design study into a an F/1.0 camera for use in a planned Astronomical spectrograph This instrument is the High Resolution Optical Spectrograph (HROS), which is part of the international Gemini project to build twin 8m aperture telescopes towards the end of the decade. The Global-Opt program allows the optical engineer to ray trace, in batch mode, up to 1 million optical systems over a period of several hours. Once complete, the engineer can explore the properties (i.e. aberrations) of these million systems in real time in order to locate the most suitable one for a particular task This is achieved by transferring the multi-dimensional optimization problem into 3 spatial dimensions in which all the aberrations and variable parameters are represented in a 'landscape' visualization. The user is then able to interact with these moving visualizations in order to attempt system optimization. Animation of these visualizations helps the user identify any features present, which directly represent specific attributes of the design form under investigation. We have noted that these moving features resemble water waves, hence the interactive optimization process described here is made analogous to 'surfing'.