Broad area diode laser and diode laser bars are the most efficient light sources. In comparison to solid state laser or gas
laser systems the over all beam quality of the diode laser is poor. Thus most application of diode laser bars is high
efficient pumping of solid state lasers converting the beam quality and scaling the power of laser systems within the kW
range. The pump efficiency and the beam coupling efficiency of the diode laser pumped systems has to be increased to
meet the increasing laser market demands for reduced costs. JENOPTIK Diode Lab GmbH (JDL) has optimized their
high power brilliance bars to enable reliable high power operation especially, for the 9xx nm wavelength range and low
far field divergences. Superior reliability with long operation time of 13,000 hours and high power operation of 200 W
are demonstrated for high power bars high filling factor mounted on passively cooled heat sinks. Smaller far field
divergence at high power levels requires longer cavity length and higher efficiencies in the beam coupling needs
requires lower filling factors. The new high brilliance bars and arrays with 20% filling factor are showing high power
operation up to 95 W and a slow axis beam divergence of less than 8° (95% power content).
Crystallographic and dispersion characteristics of muscovite at different reflection orders (2 divided by 24) for (001) lattice planes were investigated theoretically. Measurements of integral reflectivity were done for (10 divided by 38) reflection orders by using Cu and Mo X- tube radiation. Experimental results were compared with calculations for perfect and mosaic crystals. The integrated reflectivity for spherically bent mica crystals with R equals 100 and 186 mm have been calculated for various reflection orders. The results of these calculations show that muscovite crystals can be used in high reflection orders for high-resolution spectroscopy only if the crystal perfection is high enough, which provides the narrow reflection curve widths. These theoretical considerations are supported by results obtained in various plasma spectroscopic experiments. Nearly perfect muscovite crystals have been shown by using Lang and section topographic techniques for both flat and spherically bent muscovite crystals respectively. The high-quality of such crystals was also demonstrated using the scheme of obtaining a `parallel' x-ray beam and x-ray microscope schemes. Possible applications of high-quality muscovite spherical crystals are discussed.