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Radial nonsyirimetrical fiber endface microlenses original fabrication technique ha. been used for high efficient pump laser diode radiation coupling (up to 93% without AR coating) into the standard optical libers and for the form of a pump power diagram at the output fiber endfàces. Nd:GdVO4 1aer (2,5 mm crystals length) parameters with semiconfocal (output mirror curvature radius 10 cm) and monolith plane mirrors cavities have been measured for different pump diagrams formed by plane endfaces, spherical microlenses, and Selfbc lenses.Compact diode-pumped solid state lasers may be used in optical cornmunications optical storage. mediciae, and other applications. Diode laser (DL) -optical fiber coupling gives several advantages for these pumping systems -apossibility to combine of several DLs radiation, a remote DLs mounting, small size and electrical safety ofthe laser heads, simple schemes ofactive crystals cooling. axial symmetry ofthe pumping beam for longitudinal geometry.In general, high coupling efficiency between a semiconductor light source and opteal fiber may be achieved by the use of microlens, formed on the endface of the fiber. In this case bulk optical components between DL and optical fiber are not needed. In addition, the only reflection surface exists in this coupling technique.Different techniques for producing microlenses on a fiber endfa.ce-have been developed. For example. tapered hemispherical lenses [1}, melted [2], etched [3]. and polished 4] lenses are commonly used for this coupling. However, all types of such techniques produce in general radial symmetry lenses: therefor. they do not provide efl3cient coupling between a round fiber core and a nonsvmmetrical DL3s radiation.hi this paper we demonstrate the fbrication technique of fiber endfaee radial nonsymmelricai 'i1croInses S tl' radi curt ature from f mic'-omet'rs to fe ts micronetrs rindin& ?tobshmg process. This process may e used for producing aifferent nonspherical microlenses (cyindrcai, elipticai, hypercohc, etc.) to efficient coupling LS radaaton into singie-mode or muhimode optical fibers and fbr producing microlenses (including spherical) on the output fiber endface to form diagram of a pumping power. 262 ISPIE Vol. 2698 O-8194-2072-71961$6.OO Downloaded From: http://proceedings.spiedigitallibrary.org/ on 06/16/2016 Terms of Use: http://spiedigitallibrary.org/ss/TermsOfUse.aspx SiiIca'siiica optical flbers with core diameters of 100, 150 and 200 jim. cladding thickness of 152Oim and numricaI artur of 0,17-0,21 have be€n used in th pumping system. Th GaAIAs DLs with oscillating wave1enth in 808 nm range, spectral bandwidth of2-4 nrn, light emitting areas of 1 un x.120 urn in ize and cw 400 rnW output power at 800 mA driving have been used.To form a cylindncai lens at the fiber endface, for example, the fiber was glued inside a quartz ca-i1iary and fixed at the center ofa two planes rnetai pyramid with angle 90 degree at the vertex. At the first tae the pyramid planes were roughly &mded to orient the center pyramid vertex exac...

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