超连续谱激光光束质量特性

Beam quality of the supercontinuum laser beam

作为一种新型激光光源,超连续谱光源由于具有白炽灯的光谱宽度和激光的亮度,成为目前研究的一个热点,但其光束质量的评价方法至今研究报道的较少,给应用带来了不便。分析比较了各种常用光束质量评价方法的优缺点,提出用测量典型波长光束质量,结合光谱特性及光束同轴性分析评价超连续谱光源光束质量的方法,并用此方法对一台超连续谱光源的光束质量进行了测量。结果表明,超连续谱光源的光束质量与泵浦光的功率密切相关,功率较小时M2因子在1.5以下,功率较大时M2维持在1.9左右。另外,可见光部分光束质量M2因子在1.5左右,且随着泵浦功率的提高,光束质量越变越好,维持在1.3左右。

As a new type of laser source, supercontinuum has become a hot study, owing to its incandescent wide spectra and the brightness of the laser, but the reports of the beam quality are few recently. It inconveniences the application of SC. The method of measuring the beam quality of supercontinuum was put forward by analyzing and comparing the beam quality evaluation methods. The beam quality of a supercontinuum source was measured. The results shows that the beam quality of the supercontinuum source is closely related to the pump power density. The beam quality M2 factor is less than 1.5, when the pump power is small. The beam quality M2 factor is around 1.9, when the pump power is larger. In addition, the beam quality M2 factor of visible part is less than 1.5, and with the increase of the pump power, the beam quality of supercontinuum is getting better, the beam quality M2 factor is maintained at about 1.3.