الفهرس 
Literature ReviewOnly 14 pages are availabe for public view
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Abstract
A solid-state Nd3+ :Y3Al5O12 (Nd:YAG) laser is obtained by using a primary parabolic concentrator mirror mounted on a two-axis positioned tracker. Two electromechanical controlled motors were used to let the system tracking the sun during the day. One motor is responsible for tracking the sun in the vertical direction (altitude of the sun), while the other motor is responsible for tracking the sun in the horizontal direction (azimuth of the sun). The mirror is controlled through these two motors in order to get a single fixed reflected image of the sun rays during the day. The solar radiation is focused towards a non-imaging-optical fused silica light guide which focuses the rays into the secondary concentrator “compound parabolic concentrator” (CPC). The concentrated solar radiation was used for multi-pass pumping within the laser cavity from which the laser beam is obtained and directed into optical fiber to the laboratory to be used in Raman spectroscopy system and various optical projects.
-A detailed Raman spectroscopy study on an unknown sample by using the compact solar-pumped (Nd:YAG) laser as an excitation source is simulated by using a primary parabolic concentrator mirror, Compound Parabolic Concentrator (CPC) to be used as an off-grid technique for identification unknown mineral samples. The unknown sample is exposed to the laser beam as the source of exciting photons at wavelength 532 nm. The frequencies of the scattered light are measured by using a highly sensitive spectrometer which detects in the range of (350 - 1150nm) with an optical resolution of 0.2 nm and 600 g/mm. The data are processed by an optical spectroscopy software to be compared with reference libraries. This study shows that the use of solar laser in the field of Raman spectroscopy is advantageous in increasing the precision of analyzing the materials and accordingly in reducing the costs of the analyzing process. The measurements of the system were taken in the National Research Institute of Astronomy and Geophysics (NRIAG) at Helwan, Cairo