光栅

The variations of the performance of the fiber Bragg grating Fabry-Perot etalon with the length of the cavity and the reflection coefficient of fiber Bragg grating have been discussed, according to the theory of fiber Bragg grating Fabry-Perot etalon.

并利用光纤光栅法布里-珀罗标准具理论，分析了光纤光栅标准具随腔长变化的性质、光纤光栅标准具随光栅反射率变化的性质。

The present invention discloses one kind of double micro polarizing free stereo imaging device and method. The device includes image plane, slit grating and double micro polaroid. The double micro polaroid sandwiches the slit grating, and the micro polaroid in the image plane side is between the image plane and the slit grating. The double micro polaroid consists of two adjacent lines of micro polarizing units, which are orthogonally arranged.

本发明公开了一种双微偏振式自由立体成像的装置及其方法，该装置包括图像面、狭缝光栅以及双微偏振片，其中双微偏振片是指上下两层微偏振片将狭缝光栅夹在中间，其中处于图像面一侧的微偏振片处于图像面与狭缝光栅之间；所述的微偏振片由相邻两列微偏振单元的透光轴方向相互垂直的微偏振单元周期性分布构成，即所谓"正交排列"；所述的狭缝光栅由等宽度的遮光条纹平行排列组成。

The mode field of photonic crystal fiber structured with hexagon symmetry hole cladding was analyzed by coupled-mode, and the effective indexes of base mode of different wave length were got. The characteristics of this photonic crystal fiber grating were computed and simulated by coupled-mode method and transmission matrix method. Moreover, the differences were compared between conventional fiber grating and photonic crystal fiber grating on their reflection spectrum and delay.

利用多极法对包层空气孔为正六边形对称结构光子晶体光纤的模式场进行了分析，计算出不同波长下基模的有效折射率，结合使用模式耦合理论和传输矩阵法对基于光子晶体光纤的布拉格光栅特性进行了计算和仿真，对比了常规单模光纤所成光栅与相同光栅周期的光子晶体光纤布拉格光栅反射谱及时延特性之间的差异。

The location of reflection spectrum varies with the grating period (corresponding to the Bragg wavelength of FBG), thus, by changing the grating period, the reflection spectrum of SFBG can be shifted by one wavelength spacing or more.

通过改变光纤光栅周期(对应光纤光栅布拉格波长)到适当的值，使超结构光纤光栅谱位移一个或者多个波长间隔，级联多个波长精确定位的超结构光纤光栅，实现了波分复用信道滤波器的宽带滤波。

According to condition of phase resonance of fiber grating F-P cavity, the relationship between fiber Bragg grating period and cavity length for fiber grating F-P cavity has been deduced, which provide a basis for the manufacture of the F-P filter based on fiber Bragg grating.

根据光纤Bragg光栅F-P腔的相位谐振条件，推导了光纤光栅F-P腔的腔长与光纤Bragg光栅常数之间的关系，从而为研制基于光纤Bragg光栅的F-P滤波器提供了依据。

Holographic concave gratings with three stigmatic points can be implemented through considerable design. Results obtained from holographic gratings can also be applied to ruled gratings. Sphere and coma aberrations for a planar concave grating are achieved through power expansions.

通过适当的设计，可以使得全息光栅具有三个无像差点，这些分析虽然是针对全息光栅而得到的，但通过记录参数的合理选择可以将其应用到刻划光栅中去，得到等价的刻划光栅的参数。

With given parameters of the fiber grating, the transmission spectrum of the long-period fiber grating was obtained by simulation with Matlab. As a result, the position of the resonant wavelength of the long-period fiber grating is decided by the grating′s period. The attenuation changes with the length and refractive index of the grating.

在设定的光纤光栅参数条件下，通过Matlab进行模拟得到了最终需要的长周期光纤光栅透射谱，并由此得出：长周期光纤光栅谐振波长出现的位置主要由光栅的周期决定，损耗大小可以通过调节光栅长度和折射率来实现。

According to the problem that grating scale hardly achieves high resolution when in high speed and the characteristic of high speed high precision system,this paper presents across dimension displacement measuring method based on dual grating scales dual measuring,the counting values of dual grating scales switch and merge.

在分析光栅线性位移测量原理、光栅尺的测量误差尤其是细分误差的基础上，本文重点研究双光栅尺切换与合成的原理，建立了基于双光栅尺高速高精度位移测量的设计准则，根据设计准则设计了切换基准拾取方法以及快速切换与合成方法，分析了双光栅计数值切换合成的误差。

The temperature response and sensitivity enhancing technology concerning fiber Bragg gratingis analyzed.A special kind of heat-resistant polymer is used to coat FBG to enhance the temperature sensitivity of FBG sensor.The polymer coating and solidifying process of FBG is improved.A kind of heat-conducted adhesive is used to reduce the friction between tube and polymer,and eliminate the chirp effect of FBG caused by the asymmetric shrinkage of polymer during the package process.The experimental results show that the FBG sensor can measure temperature from 20℃to 180℃.

简要分析了光纤布拉格光栅的温度响应及增敏原理，采用特殊耐高温有机聚合物对光纤光栅进行温度增敏封装，并通过改进光纤光栅的聚合物封装固化工艺，使用某种有机硅导热胶减小有机聚合物与套管材料的粘合度，消除了封装过程中由于聚合物材料不均匀收缩引起的光纤光栅反射谱啁啾化，实现20~180℃范围内光纤光栅传感器对温度高灵敏度测量。

Laser-based metrology and grating-based metrology are two main ultra-precision tools of dimension measurement. However, very few research work has been done on grating-based nanometrology compared with laser-based nanometrology till now because many people, including some grating researchers and specialists, hold the idea that the accuracy of grating-based measurement is lower than the laser's and can only reach micrometre or sub-micrometre level. They consider that it is unfeasible to get nanometer-scale accuracy using grating-based sensors.

激光技术和光栅技术是毫米级以上量程的精密几何量测量的两种最主要手段，目前，用激光进行纳米测量的研究已经很多，但光栅纳米测量技术的研究却很少；很多人，包括很多光栅研究者和测量专家，都认为，光栅测量的精度不如激光，其精度还只是停留在微米量级上，用光栅来进行更高精度的测量以至纳米测量是难以实现的。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了