A micro-Gal absolute gravimeter based on high-precision and high-stability heterodyne interferometer is presented. The distance measuring technology of the gravimeter is studied in detail. The experimental results of distance measuring for a free-falling motion show that the high-precision heterodyne interferometer described in this paper can meet the demand of a micro-Gal absolute gravimeter with relative uncertainty of 6.4*10^(-9). Moreover, the heterodyne interferometer is more stable than the Mach-Zehnder interferometer (MZI) which is widely used in present absolute gravimeters.

There is an increasing demand on the measurable velocity of laser interferometer in manufacturing technologies. The maximum measurable velocity is limited by frequency difference of laser source, optical configuration, and electronics bandwidth. An experimental setup based on free falling movement has been demonstrated to measure the maximum measurable velocity for interferometers. Measurement results show that the maximum measurable velocity is less than its theoretical value. Moreover, the effect of kinds of factors upon the measurement results is analyzed, and the results can offer a reference for industrial applications.

为求解硅片表面微小粒子在任意线偏振平面入射光照射下的散射光光强分布，选择了基于Mie散射的杨氏模型为依据，推导了该模型下散射光强空间分布的计算方法，并给出了0．54μm球形粒子在垂直、倾斜入射下光强空间分布的模拟计算结果，以及入射平面第一象限内散射光强与国外已发表实验结果的比较．

A new technology of lightning location is described, which is based on detecting the state of polarization (SOP) fluctuation of the laser light in the optic ground wire (OPGW). Compared with the conventional lightning location method, the new method is more accurate, more stable, and cheaper. Theories of Stokes parameters and Poincare sphere are introduced to analyze the SOP at the lightning strike point. It can be concluded that although the initial points of SOP on the Poincare sphere are random, the SOP fluctuation generated by lightning strike can still be accurately identified by detecting the velocity of polarization motion. A new algorithm to quantify the velocity is also introduced.

A new dual-frequency laser displacement measurement interferometer with nanometer precision has been developed. An eight-pass optical subdivision technology is proposed to improve resolution based on commercial interferometers. A static positioning error measuring method has been used to examine the precision and repeatability of the laser interferometer. An optical resolution of 1.24 nm and an accuracy of nanometer scale have been achieved.

The ABCD law of parameter q for fundamental-mode Gaussian beam is deduced in this paper. The result shows that the changes of focal length and focal depth are not related to the orders of the Gaussian beam modes when focus lens moves along optical axis in a large range, indicating that the ABCD law of parameter q can be used for any order modes. A laser focusing setup is designed, and the response characteristics of oil pressure system therein are also studied.

一台具有良好光学质量的工业用5kW级横流CO2激光器研制成功。该激光器具有独特的预电离电极结构和光腔选模技术,一次充气连续密封运转大于10h,功率不稳定度为±1.0％,存放工作寿命大于1个月。利用该激光器进行汽车齿轮焊接试验,熔深可达3～4mm,焊接速度为2m/min,深、宽比可达2.5:1。

本文从理论和实验上研究了具有环状耦合、工作在稳定腔边缘的凹-凸型高功率激光稳定腔.在一台大激活体积万瓦级模流CO_2激光器上进行实验,获得了具有良好方向性的均匀的环状分布近场花样的7kw激光输出.

本文给出了高斯光束低阶横模聚焦后的焦点能量相对分布的解析解,并与不同放大倍率M值情况下的非稳腔单模远场聚焦特性进行比较。若以聚焦平面含激光总能量的80％作为光束发散角的统一基准,计算表明,在某些情况下,利用稳腔选模,可得到接近甚至优于非稳腔选模的良好光学质量,而且光腔结构简化,输出稳定性好及光电转换效率高。

本文报道一台圆柱形结构横流CO2激光器及其运转特性.圆筒长度1.45m,直径0.45m,已获得大于1kW的输出功率.