移相位

They consist of a coplanar wave-guide transmission line periodically loaded with 8 - 32 metal bridges, functioning as capacitive switches. Every switching element consists of a thin metallic membrane actuated by applied bias. Remarkable phase shifter performances were observed. 2 lAl0.96 Si0. 04 bridges MEMS Phase shifter reached to 372/3. 5mm under 20V bias at 35 GHz, the with an insertion loss (S21 of about 4 -7 dB...

该文介绍毫米波MEMS相移器的设计，研究低损耗衬底，Au，AlxSi1-x可动膜对下拉电压和传输损耗的影响，测试表明：21桥相位连续可调的分布式压控开关阵列一毫米波相移器在35GHz时，启动电压5V，20V时相移量达到372°/3.5 mm，并能在不同的控制电压下根据要求改变相移量。

This technique uses a spiral phase plate with a small central aperture placed on the Fourier plane of so imaging system. If the spiral phase filter is rotated by a certain angle around its central axis, a phase shift between the zero-order spatial frequency component and the remaining of the object is produced, and the magnitude of this phase shift is proportional to the rotation angle. Using this property, we can record a sequence of intensity distribution of the output beams corresponding to different rotation angles, and then digitally reconstruct the objects by using a phase-shifting algorithm. Both the theoretical analysis and simulation experiment results demonstrate the feasibility of this approach.

在成像系统的频谱面上放置中心带有一通光孔径的螺旋相位板，在输出面上记录输入物体经螺旋相位滤波后的输出像；将螺旋相位滤波器绕轴旋转一定角度，通过中心光孔的零频成份与其他高频成份间会产生与旋转角度成正比的相移；利用这一特点，通过记录多幅对应不同旋转角度的输出光场强度分布图，然后再用一定的相移算法实现被记录物体相位分布的数字再现。

This technique uses a spiral phase plate with a small central aperture placed on the Fourier plane of an imaging system. If the spiral phase filter is rotated by a certain angle around its central axis,a phase shift between the zero-order spatial frequency component and the remaining of the object is produced,and the magnitude of this phase Shift is proportional to the rotation angle. Using this property,we can record a sequence of intensity distribution of the output beams corresponding to different rotation angles,and then digitally reconstruct the objects by using a phase-shifting algorithm. Both the theoretical analysis and simulation experiment results demonstrate the feasibility of this approach.

在成像系统的频谱面上放置中心带有一通光孔径的螺旋相位板，在输出面上记录输入物体经螺旋相位滤波后的输出像；将螺旋相位滤波器绕轴旋转一定角度，通过中心光孔的零频成份与其他高频成份间会产生与旋转角度成正比的相移；利用这一特点，通过记录多幅对应不同旋转角度的输出光场强度分布图，然后再用一定的相移算法实现被记录物体相位分布的数字再现。

It can get the three-dimensional profile of the object surface effectively. Because of the cragginess of the three-dimensional surface when sine grating is projected the image of the sine grating is modulated and the modulated image is taken by a CCD camera with an angel compared to projecting direction. After the phase shift measuring method, the phase is gotten. Because the phase is calculated by the phase shift measuring ranges from –π to +π it isn't continuous. The phase unwrapping is necessary to recover the continuous phase about the object shape.

这种方法采用结构光照明，将正弦光栅图像投影到被测物体表面，用与投影方向成一定角度的CCD摄像机获取受物体表面面形调制的变形光栅像，根据数字相移算法计算出相位分布，由于从相移计算的相位被截断在反三角函数的主值范围内，因而是不连续的，必须通过相位展开恢复出连续相位分布，由相位－高度关系最终求出物体轮廓的三维数据信息。

The 90 and 180 phase shift bits are of reflection type, using Lange coupler to realize the separation between the incident and reflection signals. According to process rules of the GaAs MMIC product line, we properly designed the circuit layout. In order to reduce the overall chip size, the transmission lines are folded with sufficient spacing to avoid interline coupling.

结合实际MMIC工艺线，合理设计移相器电路版图，折叠微带线并留出足够大的线间距，以避免线间寄生耦合的发生，并折叠兰格耦合器使90°和180°移相位的尺寸与其它相位的芯片尺寸保持一致。

The main purpose of this paper is to improvement of isochromatics wrapped phase map can make the phase to unwrap successfully and get the physical quantity we want to know. There is a peculiar problem of isochromatic interaction in Phase-shifting techniques of photoelasticity.

中文摘要本论文主要的目的是利用负载相移法来求得相位图，并且使用相位展开的技术使相位图展开完成，得到我们所要求得的物理量-相对延迟量。

We expect it will benefit the industry field to break through the optical measuring limits at present by offering some new ideas. Optical measuring research based on moire interferometry has developed for several decades. The main idea of this research is to utilize the moire effect caused by two superimposed gratings of identical or similar spatial frequency. One is the reference grating and it is a virtual grating created by a computer program in this research; The other grating is the image of grating projected on the measured surface by the DLP projector, and this grating will distort because of the different sloped profile of the surface. To superimpose the program-created grating and the captured distorted grating will derive the so-called moire effect. This research combined the basic theory of optical interferometry and moire effect to project the different phases of the projected grating fringes by the phase-shifting method and compute the principal value of arguments between -π,π. In the end, the phase unwrapping program based on discrete Fourier transform of solving PDEs is used to unwrap the phase of the measured surface, and finally the surface profile is derived by the optical measuring system.

以叠纹干涉术为基础的光学检测研究之发展早已行之有年，而在本研究中所采用的投影叠纹法(Projection moiré)之主要精神在於藉由两道空间频率相近或相同的光栅相互叠加而成的效应，其中一道为参考光栅，而本研究中的参考光栅是以程式产生可调整不同空间频率的虚拟光栅；另一道则为投影至待测物表面的光栅影像，而在起伏高度不一的待测表面上的光栅影像会受到待测物表面起伏状况不同而在观测方向产生光栅投影条纹影像的歪曲变形，将电脑产生的参考光栅与由影像撷取装置所获取投影於待测物表面的光栅影像作叠合，便会产生所谓的叠纹效应；利用基本的光学干涉理论与叠纹效应结合，本研究中以相移法来改变投影於待测表面的光栅相位，再以相移法的理论反运算出在带有待测面各点高度资讯之介於-π，π相位主幅角，再以离散傅立叶转换解偏微分方程的相位重建程式还原待测面的相位值，以得知待测面之表面轮廓。

The relationship between the accuracy of OAF algorithm and phase shifter errors is given.

给出了这种方法的相位复原精度与移相器的位移误差之间的关系式，从关系式中可见，OAF算法大大地减小由于移相器的位移误差而引起相位复原误差。

Phase noise mainly comes from laser linewidth,laser phase offset,in/quadrature phase mismatch,90° hybrid phase imbalance,fiber channel and component in optical quadrature phase shift keyed transmission system.

在光四相相移键控系统中，相位噪声主要源于激光器的线宽、激光器的相位偏移、同相支路和正交支路相位不匹配、90°混频器的相位不平衡以及光纤和器件等引起的相位变化。

The measurement model for the retardation distributing of the quarter wave plate was introduced by Muller matrix and Stokes parameter. And four patterns with phase shifting of 90°in turn were eatched simultaneously by an especial spatial splitting phase-shifter.

1／4波片相位延迟分布的动态测量，通过密勒矩阵和斯托克斯参量法对一种1／4波片的相位延迟分布的测量模型进行了推导，并设计出一种空间分光移相器，取代一般测量系统中的检偏器，使得系统能于瞬间同时采集四幅具有90°移相步长的干涉图，避免了环境振动对测量的影响，从而可以对1／4波片的相位延迟分布进行动态在线测量。

I am accused of being overreligious," she said in her quiet, frank manner,"but that does not prevent me thinking the children very cruel who obstinately commit such suicide.""

客人们在卡罗利娜·埃凯家里，举止就文雅一些，因为卡罗利娜的母亲治家很严厉。

Designed by French fashion house Herm è s, this elegant uniform was manufactured in our home, Hong Kong, and was the first without a hat.

由著名品牌 Herm è s 设计，这件高贵的制服是香港本土制造，是我们第一套不配帽子的制服。