深圳大学：《激光原理》课程教学课件（PPT讲稿）第二章 开放式光腔与高斯光束 第六部分 非稳腔

S2.10非稳腔的几何自再现波型. Operation in the stable regime has been shownto lead to narrow Gaussian beams. This situationis not compatible with the need for high-poweroutput that requires large lasing volumes.: The nature of the coupling results in an outputbeam with a large aperture that is consequentlywell collimated without the use of telescopingoptics

§2.10 非稳腔的几何自再现波型 •Operation in the stable regime has been shown to lead to narrow Gaussian beams. This situation is not compatible with the need for high-power output that requires large lasing volumes. •The nature of the coupling results in an output beam with a large aperture that is consequently well collimated without the use of telescoping optics

一、非稳腔(unstable optical resonators)的构成双凸腔:R 1,82 >1,gi82 >1平凸腔：R 1,82 = 1,g182 >1平凹非稳腔RL,R, 0,82 L,81 0或R + R2 1

一、非稳腔(unstable optical resonators)的构成 双凸腔： 平凸腔： 平凹非稳腔 双凹非稳腔 R1  0,R2  0, g1 1, g2 1, g1 g2 1 R1  0,R2 → g1 1, g2 =1, g1 g2 1 1 2 1 2 R L R L g g     , , 0, 0 1 2 1 2 R L R L g g     , , 0, 0 1 2 1 2 R R L g g +   , 1 或 或 R L g   , 0

R/2+R/2=L特例：非对称实共焦腔2gig2 =gi +g2两个凹面镜在腔内有一个公共实焦点，构成一个望远镜系统凹凸非稳腔R, 0、RLR/2+R/2= L特例：虚共焦型非稳腔2g1g2 = g1 +g2凹面镜的实焦点与凸面镜的虚焦点相重合，公共焦点在腔外，构成一个虚共焦望远镜系统

特例：非对称实共焦腔 两个凹面镜在腔内有一个公共实焦点，构成一 个望远镜系统 凹凸非稳腔 特例：虚共焦型非稳腔 凹面镜的实焦点与凸面镜的虚焦点相重合，公 共焦点在腔外，构成一个虚共焦望远镜系统 1 2 1 2 1 2 2 2 2 g g g g R R L = + + = 1 2 1 2 1 2 2 2 2 g g g g R R L = + + = 1 1 2 R L R R L  R R 1 2   0 0 、 非稳要求：或 + 

The advantages of the unstable resonatorconcept, when the necessary conditions are metthen include:. Large, and controllable, mode volume Controllable diffractive output coupling: Good transverse mode discriminationAutomatically collimated output beams Ease of alignment and adjustmentEfficient power extraction Good far-field beam patternsend

The advantages of the unstable resonator concept, when the necessary conditions are met, then include: • Large, and controllable, mode volume • Controllable diffractive output coupling • Good transverse mode discrimination • Automatically collimated output beams • Ease of alignment and adjustment • Efficient power extraction • Good far-field beam patterns end