查询词典 optical grating

Based on the principle of grating diffraction, by using television measuring system to measure the offset between the imaging of incident laser and the optical axis to confirm the angle of incidence and the angle of diffraction of the grating, a method of measuring incident laser wavelength in far field with grating is brought up.

依据光栅衍射原理，采用电荷耦合器件CCD作为探测器，通过测量入射激光成像点在电视靶面坐标系中的脱靶量，确定光栅的入射角和衍射角，提出了一种利用固定式平面反射光栅测量远场未知方位入射激光波长的方法。

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。

To provide optical fiber: Fiber Distributed Temperature Stress Test System, Fiber Distributed Temperature Measurement System, Fiber Bragg Grating Health Monitoring System, fiber optic geophone systems, fiber Bragg grating wavelength calibration instrument and so on, which sensor product line is extremely rich and has industry representation, including: fiber optic temperature hygrometer, fiber-optic gas alarm, fiber-optic magnetic field sensors, optical fiber vibration sensor, fiber-optic high temperature pressure sensors, fiber-optic WIM system , fiber optic strain gauge welding, fiber optic embedded strain gauge, optical soil pressure gauge, fiber reinforcement meter, fiber optic pressure ring, fiber-optic displacement meter, fiber cracks meter, fiber optic osmometer, fiber-optic temperature sensor high temperature , optical fiber cable meter and so on.

北京达卡科技有限公司光纤方面提供：光纤分布式应力温度测试系统、光纤分布式温度测试系统、光纤光栅健康监测系统、光纤地震检波系统、光纤光栅波长校验仪等，其中传感器产品线极为丰富和具有行业代表性，包括：光纤温湿度计、光纤瓦斯报警器、光纤磁场传感器、光纤振动传感器、光纤耐高温高压传感器、光纤动态称重系统、光纤焊接式应变计、光纤埋入式应变计、光纤土压力计、光纤钢筋计、光纤压力环、光纤位移计、光纤裂缝计、光纤渗压计、光纤耐高温温度传感器、光纤钢索计等。

The proper optical fiber,plane directional optical grating and concave reflector were chosen and integrated together based on the theoretical computation for the optical layout of the spectrometer.

设计一种微型可见光CCD摄像光谱仪的光学结构，通过理论计算，选用合适的光纤、平面定向光栅和凹面反射镜，并将它们合理组合，采用聚焦反射和分光的方法，将待测光进行色散，直接投射到CCD接收器件的表面。

Open Linear Encoder includes main grating scale and optical encoder head. This optical encoder head includes LED light source, optical detector module, and secondary phase-grating. LED light will pass through the plano-convex lens and produces parallel light. As the parallel light pass through secondary grating, the quadratic image display on the main grating scale. And the Moire interference will be reflected from the main grating scale and detected by optical detector module, as there is a relative shift between the main and secondary grating. From detecting the periodic sinusoidal signal with phase difference 90°, the period represents the grating pitch, using the counter to detect the number of periodic signals to get the displacement, and we can adapt the technology of electron subdivide further to increase the resolution of measurement .

反射式光学尺包括主光栅尺及光学读头，光学读头包含LED光源、光侦测器模组及相位式副光栅，LED光源经平凸透镜，产生平行光穿透副光栅后，副光栅之二次成像投射在反射主光栅尺上，当主、副光栅因相对运对产生之Moire干涉经主光栅尺反射至光电检测器，检出相位差90°之周期性弦波讯号，其周期代表栅距，因此可用计数器检出周期性讯号数目得到位移量，可进一步采用电子细分割技术提高解析度。

In discussing the properties of reflection and refraction of fiber grating, the coupled-mode equation, envelope function, transform matrix formalism, multilayer and optical path approximation are used for describing the linear and nonlinear characteristic of optical fiber grating.

在分析光栅的反射和透射规律时，采用了耦合模式法，包络函数法，转换矩阵法，多层介质薄膜法以及光程法，这些方法虽然具有不同的数学和物理模型，但在分析光纤光栅这一特殊的波导结构时，可充分展现它的线性和非线性特性。

The numerical calculation shows that the space distibution of the electromagnetic field in each sub-micro-layer changes with the varing transmission depth in the relief grating, the space distribution in each sub-micro-layer is uniformer than that in isotropic grating and the optical parameters of the anisotropic relief grating and the incident beam have a large impact on the space distribution of the electromagnetic field in relief grating and so on.

数值计算表明，光波场光强的空间分布随透射深度的变化而变化，各向异性介质光栅体内光波场的空间分布相对各向同性介质要均匀，光栅材料的性质参数和光束的入射参数对光波场光强的空间分布有较大的影响等。

This paper analyzes the optical characteristics of fiber grating according to the theory of mode-coupling in nonsymmetrical optical wave-guide, which affords the gist for the testing of optical characteristics and tuning characteristics of fiber grating. Moreover, we deduce the linear relationship between reflected wavelength shift of fiber grating and vertical displacement of cantilever beam which the fiber grating is sticked on.

论文根据非均匀光波导中的模式耦合理论，分析讨论了光纤光栅的光学特征，为光纤光栅的光学特性和调谐特性的测试提供理论依据；并根据材料力学原理推导了光纤光栅波长漂移量与侧向位移的线性调谐关系。

Fiber grating coupler has good wavelength selection characteristic of optical fiber grating as well as multiport advantage of fiber coupler. These features make it easy to realize allfiber optical add/drop multiplex.

光纤光栅耦合器具有光纤光栅良好的波长选择特性和光纤耦合器的多端口特点，易于实现全光纤的光波分插复用。

By adjusting the positions and angles of the two DVD optical pick-up heads, the relative distance of the two laser spots can be equivalent to one quarter of the grating pitch. When the grating moves, the surface profile of the grating can be measure directly, in order to obtain the two quadrature sinusoidal signals. Then by counting the zero crossing of these two quadrature sinusoidal signals and calculating the interpolation value of these two quadrature sinusoidal signals, the moving direction and moving displacement value of the grating can be obtained.

采用两个光学读取头，且两个光学读取头共用同一分光镜与同一聚焦物镜，於搭配光路的设计，可使两个光学读取头之光束打入同一聚焦物镜，藉由调整两个DVD光学读取头的位置与角度，使聚焦物镜聚焦的两相近聚焦光点的距离相等於四分之ㄧ光栅尺间距，当光栅尺移动时，可直接量测光栅尺的表面轮廓变化，以获得一组正交的弦波讯号，继而利用讯号四分割与细分割处理，计算出光栅尺之移动方向与移动量。

Do you know, i need you to come back

你知道吗，我需要你回来

Yang yinshu、Wang xiangsheng、Li decang,The first discovery of haemaphysalis conicinna.

1〕 杨银书，王祥生，李德昌。安徽省首次发现嗜群血蜱。