Sogol Tadayoni, Mahdi Shayganmanesh,
Volume 13, Issue 2 (International Journal of Optics and Photonics (IJOP) Vol 13, No 2, Summer-Fall 2019)
Abstract
In this paper propagation of combined laser beam through atmosphere is investigated. Laser beam is combined via lens array arrangement. Turbulence is considered as an affecting factor of atmosphere and its effects on transverse coherence length (Fried parameter), peak intensity, propagation efficiency, and spot size of the laser beam is investigated. Coherent and incoherent combined beam are compared. It was seen that irrespective of laser beam quality in weak and medium turbulence levels, propagation efficiency parameter in coherent and incoherent beam combining has almost the same values. Therefore replacing incoherent beam combination with coherent is proposed.
Dr. Mehdi Shayganmanesh, Dr. Davood Razzaghi, Ms. Maryam Goli Hasanlo, Ms. Arezou Jalilzadeh Heydarlou, Dr. Marzieh Akbari, Dr. Mohammad Reza Moghaddam,
Volume 18, Issue 1 (10-2024)
Abstract
In this paper, the thick thermal lens approximation is evaluated for a CTH:YAG laser with a standard telescopic resonator. An accurate relation between the thermal lensing parameter and lens-like media factor is proposed. Telescope adjustments were studied based on the practical values of the focal length of the thermal lens. The fundamental mode volume is determined regarding the Hermit-Gaussian theory, and the influence of the defocus parameter is examined. The study emphasizes the importance of considering both the fundamental mode volume and the distance to the stability boundary when selecting the optimal defocusing parameter. A merit factor was introduced that provides a comprehensive approach to selecting the most suitable defocus parameter for the system.