Studies of Diode-Pumped Neodymium Doped Yttrium Orthvanadate (Nd:YVO4 ) Near-Infrared and Green Frequency- Doubling Laser

• Main Authors: Michael Tung, 董畯豪
• Other Authors: Wu Kun-Dong
• Format: Others
• Language: zh-TW
• Published: 2001
• Online Access: http://ndltd.ncl.edu.tw/handle/90246344965477756291

碩士 === 輔仁大學 === 物理學系 === 89 === At present , sorts of developed laser light sources still have restrictions on the range of the containing wavelength . The technique of lasers producing optical second harmonic generation (SHG) by frequency- transforming crystals just provides the source of other wavelength . A miniature , easily fabricated , and cheap solid state laser system without any cooling equipment presents great potential on commercial purpose . With kinds of active medium gradually developed , it is more important to styles of lasers made by the technique of intercavity optical second harmonic generation . Green frequency-doubling laser manufactured by Nd：YVO4 / KTP crystal supplies manifold applications . In the respect of low power applications , it can be used to be the source of light information storage system , laser pointer , and light coherent communication . It can be one of three primary element colors for the needing of laser display , too . In this thesis , we are aimed at Nd-doped YVO4 near-infrared laser and green frequency-doubling laser . This design made of hemi-spherical cavity , which is extremely simple , represents a miniature low power 1.064 infrared laser by 1 % , 2 % , 3 % Nd-doping density , and 1 mm , 2 mm , 3 mm YVO4 crystal . The influence of these two factors on the performance of output power was investigated . We find in 1 mm YVO4 crystals , laser used by 2 at.% Nd-doping crystal has higher output power . Crystal length is 2 mm or 3 mm , 1 at.% Nd-doping crystal gets higher output power . To the part of green laser , we put KTP crystal in the hemi-spherical cavity to produce green frequency-doubling laser , and find the relation between input and output power . The difference of conversion efficiency measured from a miniature , monolithic green SHG laser are compared with the crystal coating on the two end faces , which is stuck Nd：YVO4 and different length KTP together . It is found that the longer KTP length increase , the higher conversion efficiency of green frequency-doubling laser improve .