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.
Colleagues as Change Agents: How Department Networks and Opinion Leaders Influence Teaching at a Single Research University
This study investigates colleague–colleague relationships within life sciences departments and how they may promote teaching reform. The authors found that discipline-based education researchers are perceived as promoting changes among colleagues in views about teaching and teaching practices. Other faculty may also be leveraged to support change.