光束

It's very important to understand that this was unconnected with electromagnetics, hidden microphones, targeted beams, or anything else of that nature.

非常重要的一点是，这是与电磁、隐藏的传声器定向电波光束或其他类似性质的东西毫无关联的。

Examples are charged particle beams , an electron cloud in a Penning trap , and positron plasmas.

例子是带电粒子光束，一个电子云在潘宁陷阱，和正电子等离子体。

To make picture clear, the electron beam that must come out to be being hit from electron gun undertakes focusing is handled, let electron beam pass electron lens, be opposite with optical lens of beam of light collect action likeness, the electron beam assemble that opens scattering rises, get on fluorescent screen one shines again small spot, add the effect of scanning circuit, ability shows clear picture.

为了使图像清楚，必须对从电子枪打出来的电子束进行聚焦处理，让电子束通过电子透镜，和光学透镜对光束的聚集功能相似，把散射开的电子束会聚起来，在荧光屏上得到一个又亮又小的光点，加上扫描电路的功能，才能显示清楚的图像。

However, the output beam quality of semiconductor laser is poor. Because of the waveguide properties of their active areas, semiconductor lasers generate large divergence-angle beams with elliptically shaped intensity profiles.

由于半导体激光器的结构特点，使得它发出的光束在垂直于结平面方向上远场发散角和平行于结平面方向的远场发散角相差较大(在垂直和平行于结平面方向上的发散角大小分别在30°左右和10°左右)。

The results show that the changes of spatial degree of coherence in x and y oriention and the ellipticity influence the tolerance between peak and valley.

结果表明，x和y方向的相干度变化，以及光束偏心率的大小都直接影响着归一化曲线的峰谷间差值△T的大小。

Since the need of the reality, the higher output energy of high power solid-state laser facility is demanded.

然而，在现实需求的牵引下，人们对高功率、高能量光束的输出提出了更高的要求。

I remember a dark dream for many days, then a light enveloped me..

我回忆起一个做了许多天的黑暗的梦，然后一道光束包围住了我。

In order to study the nonuniform temperature rise and thermal effect in the Yb:YAG crystal,based on the theory of semi-analytical thermal analysis and working characteristic analysis of Yb:YAG microchip with super-Gaussian beam end-pumping and back-face cooling,a new solution of heat conduction equation was introduced and the general expressions of temperature field,thermal distortion field and additional optical path differences of Yb:YAG microchip were obtained respectively.

为了研究抽运光在Yb：YAG晶体内产生的非均匀性温升以及引起的热效应问题，以半解析热分析理论为基础，结合超高斯光束端面抽运、背向冷却Yb：YAG微片工作特点分析，采用热传导方程一种新的求解方法，得出了Yb：YAG微片内部温度场、热形变场、附加光程差的半解析计算表达式。

The infrared beam from an erbium laser is absorbed efficiently by the tooth but poorly by the gums.

来自铒激光器的红外光束能够被牙齿有效地吸收，但是牙龈却不行。

Compared with Crank-Nicholsonscheme in the same computational time and resource, the method has two characteristics: small truncation error of o 4 in the transverse direction and high accuracy.

在诸多的计算方法中，有限差分光束传播算法(Finite differencebeampropagationmethod ，FD BPM算法) [2 ] 是一种目前光波导器件中分析模拟光波传输应用最广泛有效的分析方法之一。

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％。