Study on a quasi-CW Nd:YAG frequency-doubled laser at 660nm
A QCW Nd:YAG intracavity frequency doubled red laser was made. Using a flat—flat laser cavity, 2 Kr-lamps, KTP crystal and an AO Q-switch, 2 W output power at 660 nm was obtained. The relationship between laser cavity length and output power is analyzed.
Methods and experiments for dealing with the solid state laser beam with lower order mixing modes by Gaussian-like distribution
For solid state lasers with lower order mixing modes in which TEM00 mode is dominant and a few lower order modes are included, a method of dealing with the beam based on Gaussian-like distribution is presented. The beam of lower order mixing modes may be regarded as a fundamental mode Gassian beam expanded K times. (K is the multimode coefficient). Firstly, from the calculation of intensities and spot sizes of the mixing modes and the fundamental mode, the justification of this assumption is indicated. Then the calculating formulae for the beam characteristics of the mixing modes are given. By Gaussian-like method, a typical continuous wave YAG laser is analysed and the region of the optimum cavity length is found. After that, the experimental method of measuring the value of K is recounted. Finally, the coupling of the laser output beam with a fiber is discussed, the necessary parameters for the practical application are obtained.
Solitary Orbital Paget Disease: A Case Report
Purpose: To describe the clinical findings in a patient who had developed painless supraorbital prominence. Methods: Clinical and histopathological findings of the case are reviewed and presented. Results: The patient had an isolated histologically confirmed Paget disease of the orbit. Local excision of the lesion was performed. Conclusion: Paget disease can present not only as a diffuse process but also as a painless, solitary lesion of the orbit.