题名 | 激光介质动态热畸变的测量方法研究 |
作者 | 刘佳 |
学位类别 | 硕士 |
答辩日期 | 2007 |
授予单位 | 中国科学院上海光学精密机械研究所 |
导师 | 胡企铨 |
关键词 | 激光介质 热畸变 干涉条纹 图像处理 |
其他题名 | Research on measurement method for thermal dynamic distortion of laser medium |
中文摘要 | 本文主要是针对激光介质动态热畸变的测量方法进行了研究。研制出一套基于Mach-Zenhnder干涉仪的激光介质动态热畸变的干涉测量装置,该干涉测量装置的关键就是从随时间变化的干涉图像上测出每点的条纹位移量 ,从而得到被测激光介质的光程差分布。再根据光程差与被测物理量之间的关系,确定被测物理量的分布。 为了获得精确的定量结果,必须对采集到的干涉条纹进行图像处理。本文重点讨论了干涉图像的滤波、二值化、干涉条纹细化、条纹断口连接算法,干涉条纹的选择等,并且在中心细化算法的基础上提出了一种针对本文干涉条纹图像特征的简单快速的细化算法。经过图像处理后的干涉条纹能够精确的判读出位移量。 从Mach-Zenhnder干涉仪的干涉原理出发,以侧面抽运板条激光介质为模型,分析了实时动态干涉条纹的位移量与板条激光介质内的温度分布及干涉条纹的位移量与透过板条介质的波面畸变之间的对应关系。 在实验研究方面,采用了温度控制系统给N31激光玻璃板条两侧面加载均匀温度梯度场方法来测量该玻璃板条的热畸变情况,利用采集到的动态干涉条纹对该玻璃板条的热畸变进行了分析,得到了玻璃板条在热传导过程中瞬态温度分布和波面畸变情况,并且利用Ansys软件模拟了该玻璃板条在预设的温度梯度中的温度分布情况,与实验结果相符,充分验证了该测量方法的可行性,并进一步证实了该方法可以应用于其它抽运方式和不同形状的激光介质动态热畸变的测量,为动态补偿激光介质热畸变提供可能。 |
英文摘要 | The article studies the measurement method for dynamic thermal distortion of laser medium. We developed a device based on Mach-Zenhnder interferometer to measure dynamic thermal distortion of laser medium. The key of the device is to get the displacement of every point from the time-dependent interference fringe, and then we can get light distance distribution of the laser medium. Therefore, based on correlation of light distance and the parameter to be measured, and then we can get the parameter to be measured. To get the accurate parameter, we should process the interference fringe by computer. The article emphasizes in discussing the filter of interference, binarization, thinning algorithm, algorithm of break connection, and choice of interference fringe. Based on center-thinning algorithm, we put on an easy and fast thinning algorithm which is suitable for the interference fringe we shot. Then, the interference fringe image has been processed by computer; we can get the accurate displacement. Based on the theory of Mach-Zenhnder interferometer, model a side-pumped slab laser medium. We analyzed the correlation of dynamic interference fringe and the temperature distribution of slab laser medium; also we analyzed the correlation of dynamic interference fringe and the wave front. On the aspect of experiment, in order to measure N31 laser glass slab, we used temperature controlling system to give temperature grads to it. We analyzed thermal distortion of laser glass slab, and got transient temperature distribution and wave front distribution during heat exchange. And we used software to simulate the temperature distribution. The experiment result matched theory result. Then the result validated that the measurement method is feasibility, and more, validated the measurement method also can be broad used in other pump mode and deformity laser medium. It paves the measurement method to dynamically compensating the thermal distortion of the laser medium. |
语种 | 中文 |
内容类型 | 学位论文 |
源URL | [http://ir.siom.ac.cn/handle/181231/16494] ![]() |
专题 | 上海光学精密机械研究所_学位论文 |
推荐引用方式 GB/T 7714 | 刘佳. 激光介质动态热畸变的测量方法研究[D]. 中国科学院上海光学精密机械研究所. 2007. |
个性服务 |
查看访问统计 |
相关权益政策 |
暂无数据 |
收藏/分享 |
除非特别说明,本系统中所有内容都受版权保护,并保留所有权利。
修改评论