Collimating beam shaper for holography and interferometry

Beam shaping is important technique to improve holographic and interferometric technologies, and refractive field mapping beam shapers like piShaper demonstrate strong capabilities in increasing predictability and reliability as well simplifying the realization of the mentioned technologies. Most often the piShaper are implemented as telescopic systems with collimated beams at entrance and exit. At the same time the fiber-coupled TEM00 laser sources become more popular in holography and interferometry because of their high beam quality, reduced high frequency noise due to spatial filtering in a TEM00 fiber and convenience in usage. Therefore, the beam shapers should be compatible with those fiber-coupled lasers featured with high beam divergence. Basic piShaper design principles allow to implement a system combining the functions of beam shaping and collimation, as result divergent Gaussian laser beam from TEM00 fiber is transformed, almost lossless, to collimated flattop beam with low divergence, flat wave front, extended depth of field, reduced noise; such a beam is optimum for SLM-based technologies of CGH, Dot-Matrix mastering of security holograms, multi-colour Denisyuk holography, holographic data storage, holographic projection, lithography, interferometric techniques of Volume Bragg Gratings recording, periodic structuring, etc. Achromatic design of the telescopic and collimating beam shapers allows working with several laser sources with different wavelengths simultaneously that is, for example, important in multi-colour Denisyuk holography. This paper will describe some design basics of collimating refractive beam shapers of the field mapping type and optical layouts of their applying in holographic systems. Examples of real implementations and experimental results will be presented as well.