| 1. | Study of sol - ton tramsmission and coupling in heat - lens effect of photorefactive crystal
光折变晶体热透镜效应中光孤子传输与耦合特性的研究 |
| 2. | Due to the special structure design and the utilizing of the low thermal expansion materials , the folded resonator of the unit is stable both mechanically and thermally
通过特殊的结构设计，使其具有机械和热稳定性。对输出窗口的热透镜效应进行了理论分析，并对其进行了部分补偿。 |
| 3. | If a nd : yag laser runs at high pump power , laser resonator will generate multimode beam due to thermal lens of active rod . the higher pump power is , the bigger divergence occurs and the smaller rayleigh range is
当nd ： yag激光器工作在高泵浦功率下时，由于nd ： yag激光器工作物质的热透镜效应导致了谐振腔输出多模激光，随着泵浦功率的升高激光光束发散角增大，焦深减小。 |
| 4. | In the third chapter , the thermal lens effect of laser crystal is studied . the model of thermal lens theory and some measuring methods are explored . these methods are generalized and classified and the advantages and disadvantages of which are pointed out
第三章分析了激光晶体的热透镜效应，研究了热透镜理论模型和各种测量方法，对这些方法总结、归类并指出了各自的优缺点。 |
| 5. | The optimum position of focal spot of pumping laser through coupling system is calculated . in the fifth chapter , the optical characteristics of nd : yvo4 and lbo are studied . the astigmatism problem of resonant cavity is explored thoroughly under the condition of thermal lens effect
第五章分析了nd ： yvo _ 4和lbo晶体的光学特性，深入分析了在引入热透镜效应的情况下谐振腔的像散问题，设计了四镜z型折叠腔，应用abcd定律计算优化选择了一组腔参数。 |
| 6. | But the absorption efficiency , stokes efficiency , quantum efficiency and the superposition efficiency between pump mode and cavity mode is less than one respectively , so the local heat absorption of the crystal is quite strong , and its thermal effect is quite obvious . two measures were taken
但是，由于量子效率小于1 ，斯托克斯频移，泵浦光与基模的非完美空间重叠以及激光晶体的偏振吸收等因素积聚在晶体内的热量随泵浦辐射而变化，出现更为复杂和明显的热透镜效应。 |
| 7. | Based on the rate - equation theory of four - level system , the expressions of threshold pump power , output power and slope efficiency are given . the influence of space distribution of pump light ( the position of focusing point , dimension of pumping light and divergence angle ) to the output characteristics are also discussed . then , by investigating the effects of thermal effect of laser crystal on the size of laser cavity mode , we obtain the mode - matching principle of high power laser diode end - pumped solid - state lasers
其中，在泵浦光的空间分布变量中我们分别考虑了泵浦光聚焦后的腰斑大小、聚焦腰斑在增益介质中的位置以及泵浦光在介质中发散角的影响；然后我们研究了在高泵浦功率下激光晶体因吸收泵浦光而产生的热效应所导致的热透镜效应以及热致衍射损耗，通过分析它们对振荡激光腔模尺寸的影响，得到了高功率半导体激光二极管端面泵浦固体激光器模式匹配的要求，为高功率连续单频nd ： yvo _ 4激光器的优化设计提供了理论依据。 |
| 8. | Because of high threshold of 946 nm laser , severe thermal lens effect will appear when the 946 nm laser operations . in the consideration of thermal lens effect , the - optimized folding cavity has been devised . the relation between thermal lens effect and the radius of laser beam waist has been given as well
由于946nm激光阈值很高，需要更强的泵浦功率密度，因此较大功率蓝光激光器的热透镜效应将会比红光和绿光激光器更明显，而热透镜效应是影响激光功率提高和激光输出稳定性的重要原因，所以在考虑到激光晶体热透镜效应的情况下，优化设计了折叠腔结构，并给出了热透镜效应和折叠腔中腔模半径大小的关系。 |
| 9. | First , some principle that should be considered in building a laser cavity was discussed based on the rate equation of four - level laser model . then , the thermal lens effect of nd : yvo4 crystal was analyzed and estimated theoretically . the laser cavity was designed by considering the thermal lens effect and the optimal transmission was estimated
首先在理论上通过四能级激光器速率方程，讨论了激光器设计上需要注意的一些原则，然后分析了nd ： yvo _ 4晶体的热透镜效应，理论上估算了其热焦距的大小，并且在腔型设计中给予了考虑。 |
