Studies to enhance the beam quality from flashlamp-pumped dye lasers

摘要

Abstract: A number of techniques have been considered for reducing the divergence of the beam of energy generated by a flashlamp pumped dye laser, particularly for those lasers with a high Fresnel number. the principal motivation is to enhance the brightness of such laser beams. The techniques that have been evaluated, or are under active investigation, include: solvent effects; unstable resonators; telescopic resonators; oscillator amplifier configurations; and phase conjugation techniques. Results are presented that show that judicious choice of solvents can give a modest reduction in divergence and improvements of at least a factor two in beam brightness. More sophisticated techniques such as the use of a telescopic resonator can enhance the brightness by a factor in excess of 200. There is scope for further improvement in beam quality by suitable combinations of techniques or materials. !10