光束

Furthermore, a new method for evaluating beam quality of laser diode is given.

在此基础之上，提出了一种新的针对激光二极管光束质量评价方法。

For the diffractive optical element realizing beam shaping in the fractional Fourier transform domain,the transform matrix calculated by the discrete sampling points was compared with that calculated by the Fresnel integral,and the discretization error of the intensity distribution on the output plane was qualitatively obtained.

针对分数傅里叶变换衍射光学光束整形器件，比较了按离散点与按菲涅耳积分计算得到的变换矩阵间的差距，从中分析得出按离散点计算的变换矩阵引入的离散化误差与分数傅里叶变换系统参数的关系。

Image pickup is accomplished by using electromagnets to deflect the entire beam past a pinhole located in the back of the dissector tube.

图像摄取是通过电磁石把整个光束转，并穿过解析器背后的一个小孔获取。

And the space distribution characteristics of the output beam were analyzed and investigated.

根据展开结果，对TEA CO2激光器输出光束的空间分布特性进行了分析与讨论。

And the far field divergency angles of the output beams are detected experimentally, the results illustrate that compared to the single UR90, this new coupling technique may nether weaken the mode control ability, nor effect the beam quality.

此外，还利用铜蒸汽激光器实现了两台放大率M=1.21的UR90腔和两台放大率M=1.5的环状输出UR90腔的相干并束输出，并对输出光束的远场方向性进行了测量分析。

It thus can travel great distances without diverging from a tight beam.

因此，它可以发射到很远的地方而不从密集的光束中发散。

Based on the study of division of amplitude photo polarimeter, the principle of a division of amplitude photo measuring BCPM is introduced in this thesis. Simultaneitily, it has made a research on sues for the characters of light source for survey.

本文介绍了分振幅测量斯托克斯参量的方法，在此基础上进行光路的改造，提出了相干偏振矩阵测量的基本原理以及其对待测光束入射条件的要求，然后进行了测量系统软、硬件设计。

We use Dammann gratings to generate multiple beamlets by division of amplitude on ultrashort laser pulses.

利用分振幅方法，我们通过达曼光栅可以将单次脉冲变换为多束子光束。

Laser Doppler Velocimeter:the two times Dopper effect for the scattered light from the tracing particle, the formula of LDV, laser heterodynes measurement, dual beam differential mode, LDV signal processing, frequency shift technique and application, multi-dimension velocity measurement, LDV application while light is refracted.

三。 激光多普勒测速：运动粒子中散射光的二次多普勒效应（1），LDV基本公式(1)，光外差检测技术及其实现(1)，双光束差动模式(1)，LDV信号处理(3)，频移技术及其应用(5)，多维速度的测量(5)，有折射现象时LDV的应用(3)，LDV测量实例(1)。 LDV实验一：LDV光路实验（3） LDV实验二：LDV测水流场实验（3）四。

The Gaussian properties of laser beams may cause the appearance of gradients in the interference pattern in the measuring volume and a broadening of Doppler spectrum....

本文定量地论述了高斯光束的各因素对测量精度的影响；给出了测量误差表达式，经过各种情况下的理论计算值的对比和分析，得出了两束腰分别在测量区两侧，等距离时，干涉条纹空间频率梯度引起测量误差最小的结论。

Breath, muscle contraction of the buttocks; arch body, as far as possible to hold his head, right leg straight towards the ceiling (peg-leg knee in order to avoid muscle tension).

呼气，收缩臀部肌肉；拱起身体，尽量抬起头来，右腿伸直朝向天花板（膝微屈，以避免肌肉紧张）。

The cost of moving grain food products was unchanged from May, but year over year are up 8%.

粮食产品的运输费用与5月份相比没有变化，但却比去年同期高8％。