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It is well known that aspherical surfaces (AS) can solve many problems in optics which are practically unsolvable now. These problems relate to producing high quality microlenses for endoscopy, microscopy, optical recording etc. But probably the most important direction for AS application today is transformation of astigmatic radiation of diode lasers, lines and matrixes. Well—known pecularities of semiconductor laser sources (SLS) are: 1) different numerical apertures at fast and slow axis and correspondingly elliptical cross-section of laserbeam with semi—axis ratio from 2-4 till 10 and 2) axial astigmatism connected with different positions of emitting planes (up to 20-80 JLm) for fast and slow axes [11. Due to these pecularities of SLS most optical devices with SLS require beam collimation and (or) symmetrization components. There were many new optical solutions suggested in the last years for this purpose. Refractive optical components like optical cubes [2], anamorphic optical elements [3], GRIN rod—lenses [4], diffractive optical elements [5] etc one can find among them. From many points of view, aspherization of refractive optical components or the use of combined aspherical and GRIN lenses looks preferable to improve the quality of SLS radiation [6, 7]. The problem of aspherical optics creation can be divided into three tasks : 1) calculation of AS, 2) fabrication and 3) measuring and testing. The first of them can be solved now practically for any optical device due to the progress in computer hardware and software. The third task is not new and is very difficult and very specific for every AS. But most complicated till this time is the task of fabrication of AS — it requires a universal, exactly controlled method of removal of material from the surface of an optical component. In this paper, based on many years experience of laser treatment [2, 8, 9], a new conception of aspherical optical surfaces fabrication is suggested. The main idea of this work is combination of two laser—assisted processes in time and space, such as laser shaping by removal of material and smoothing by laser thermal polishing. The general approach to the problem of AS fabrication is described by the example of the aspherization of cylindrical surfaces, most important for SLS. And this only addresses the task of beam collimation in the fast axis. In this case, the SLS beam after optical component should be transformed into a diffraction limited beam at the fast axis and it remains at its initial divergence at the slow axis.
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