Study on the Improvement of the Stability of the Laser System Used

There is a very strong interest to achieve stability from mode-locked laser beam for satellite laser radar station at Helwan by using a more simple stable and easier mode-locker. The energy stability of the laser output can improve the accuracy and reliability of the Helwan satellite laser ranging station ranging data remarkably. Normally the saturable absorber dyes dissolved in dichlorethan has been used for Q-switching and Mode-locking of this system for many years. Decomposition and degradation of this type of mode-locking is a disadvantage simply because it is not permanent and needs to be mixed and to be renewed often every 5-10 working nights). It''s also poisonous; and dissolved in a highly flammable solvents besides the energy stability of the resulting pulses is not high. All of these reasons gave rise to the idea of this work which is to study the possibility of using other more suitable safer and easier-to-install mode-locker which can result in a better output stability of the system.