Computations on wavefront aberration function.

In this work, a code of ray tracing programs has been constructed. This code includes programs for:1.Paraxial ray tracing. 2. Skew ray tracing for spherical surfaces. 3.Skew ray tracing for Cartesian or quadric surfaces of revolution (conic surfaces). These programs have been employed to calculate Seidel Sum Expressions of the primary (third-order) aberrations for the evaluation of the optical system. Particularly, the paraxial ray tracing program, has been employed to obtain the Gaussian properties of an optical system and it may be used to design achromat lenses, i.e., correcting the chromatic aberration with treated spherical and coma aberrations of lenses. The primary wave front aberration function instead of the rays (transverse and longitudinal) aberrations; because of its physical significance over rays aberrations; has been considered as a measure to exhibit the performance of any optical system. This procedure has been considered to exhibit the performance of an astronomical space-based telescope, regardless of the severe environment of space, by substituting Siedel terms of the primary aberrations in the corresponding coefficients of the wave aberration function. This substitution or replacement is of a great utility; it provides flexibility to minimize, directly, the wave front aberration and consequently improving the optical system performance through modifying the system parameters (design parameters), which are implanted in Seidel Sum Expressions, during the process of designing each element individually or the whole system globally. The reflecting part of the telescope under investigation is a two mirror system, both are hyperboloid. So, the used programs for extracting the mirrors parameters and evaluating their performance based on the skew ray tracing for conic surfaces. The refracting part of the telescope is a quadruplet system (camera lenses),
especially, designed for space-based telescopes. Its performance has been evaluated through programs based on the exact ray tracing for spherical surfaces. The final results of this work exhibit the wave front aberration as a function of the normalized exit pupil for each element of the above design.