共查询到20条相似文献,搜索用时 795 毫秒
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针对全息波导显示系统中输入光栅、转折光栅和输出光栅的光栅参量不一致,导致系统设计和光栅制作难度增大的问题.对比正常配置和锥形配置下的光栅方程,可得全息波导显示系统中全息光栅具有相同周期需要满足转向光栅60°锥形配置.由此提出波导侧面装有反射镜的三光栅单波导板显示构型,其中三个光栅周期完全相同,输入光栅和转向光栅条纹走向一致.使用光学设计软件CODE V对该构型进行仿真,验证了该构型的可行性.与传统全息波导显示构型相比,侧面反射镜的光路折叠作用使得该构型系统无效显示面积和耦合效率损失减小;三个光栅周期相同且输入光栅和转向光栅条纹走向一致,可以降低系统设计和全息光栅制作难度.该构型可以用于虚拟现实显示或者头戴式显示. 相似文献
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利用二维耦合波理论,研究了用短波长记录全息光栅而用通讯波段内的长波长读出时,用于90°结构垂直读出平板型的光折变局域体全息光栅的衍射性质.讨论了局域体全息光栅的几何尺寸对其衍射效率及光栅布喇格选择性的影响.结果表明,随着光栅的纵向和横向尺寸的增加,光栅的衍射效率也逐渐增加.当光栅的纵向和横向尺寸发生改变但光栅的总面积不变时,光栅衍射效率保持不变.此外,随着光栅尺寸的增加光栅的布喇格选择性越好.在利用短波长记录全息光栅而用长波长读出的光学器件设计过程中,为了获得最佳的衍射效率及其布喇格选择特性,应当根据要求合理地设计光栅的几何尺寸. 相似文献
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The low divergent Dammann grating is researched for the potential applications in aerospace. A laserbeam writing system is developed for writing the low divergent Dammann grating. The uniformity and efficiency of the Dammann grating are presented in this letter. The novelty of this letter is to demonstrate a low-cost and effective method to fabricate low divergent Dammann grating. 相似文献
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采用每毫米1000线的自支撑透射光栅配上背照射软X射线CCD(charge coupled device)组成了透射光栅谱仪,利用北京同步辐射装置(BSRF)3W1B光束线软X射线实验站上X射线源分别对透射光栅的衍射效率和软X射线CCD的响应灵敏度进行了准确的实验标定,获得了150eV到1500eV能区的绝对衍射效率和响应灵敏度的实验结果;同时在国内外研究工作的基础上,发展了自己的透射光栅衍射效率理论计算模型和X射线CCD响应灵敏度计算模型,开展了相应的理论计算和实验标定结果比对工作,理论和实验符合较好, 相似文献
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S. R. Abdullina S. A. Babin A. A. Vlasov S. I. Kablukov 《Optics and Spectroscopy》2007,103(6):1007-1011
A tuning method of a fiber Bragg grating by the bending compression-tension is considered. With this method, a relative tuning range of the resonance wavelength of the grating of about 5% has been obtained. The changes in the shape of the spectrum and in the grating reflectivity during the tuning process are studied. The reflectivity of the fiber Bragg grating has been found to considerably increase with increasing degree of compression. It is shown that such an increase is caused by compression-induced changes in the refractive index modulation amplitude in the grating. The fiber Bragg grating developed has been applied for tuning the radiation wavelength of an ytterbium fiber laser. The tuning range of the laser has been found to be 45 nm around the central wavelength 1080 nm. 相似文献
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高光谱分辨率紫外平场光谱仪的研制 总被引:1,自引:0,他引:1
光栅作为一重要的分光元件,广泛应用于各类光谱仪,其中球面变线距平场光栅以其独特的平场特性使其容易与阵列探测器结合使用,一次实现宽光谱范围的记录。商业球面平场光栅一般只会提供光栅的公称线密度以及相应的安装参数,而不会提供光栅具体的变线距参数,并且提供的安装参数是针对整个使用波段优化的结果。使用者往往只需要其中的一部分波段。针对这种情况,根据球面平场光栅聚焦、分光原理,利用生产厂家提供的光学元件安装参数给出了推导球面变线距光栅变线距参数的方法。并给出了利用这些参数,根据光谱仪的实际工作波段确定最佳的CCD安装位置的方法。根据推导的光栅变线距参数可以对光学系统进行光学追迹已验证光学系统的性能。研制了一台高分辨率紫外平场光谱仪,覆盖光谱范围230~280 nm。采用的球面变线距光栅公称线密度为1 200 lines·mm-1,使用波段为170~500 nm。推导了该光栅的变线距参数,并针对230~280 nm波段对CCD的安装位置进行了优化。同时利用不同元素的标准光源空心阴极灯对光谱仪进行了波长标定和光谱分辨率测试。波长标定采用参数拟合法,整个波段范围内的标定精度优于0.01 nm。光谱分辨率测试的结果表明光谱仪的光谱分辨率达到0.08 nm@280.20 nm。 相似文献
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Optical fiber Bragg grating sensors have found potential applications in many fields, but the lack of a simple, field deployable and low cost interrogation system is hindering their deployment. To tackle this, we have developed a micro optical sensor interrogator using a monolithically integrated planar lightwave circuit based echelle diffractive grating demultiplexer and a detector array. The design and development of this device are presented in this paper. It has been found that the measurement range of this micro interrogator is more than 25 nm with better than 1 pm resolution. This paper also reports the applications of the micro interrogator developed to the monitoring of commercial optical fiber Bragg grating (FBG) temperature sensors and mechanical sensors. The results obtained are very satisfactory and in some cases, they are better than those obtained using commercial bench top lab equipment. 相似文献
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The reflection grating method is a special case of the well-known reflection moiré principle. Whereas this moiré effect is suitable for measurement of the slope and curvature of deformed object surfaces by superposition of at least two grating images, the same results can be determined using only one reflected grating image without moiré lines.Some fundamental relationships between grating lines, optical setup and the desired deformation are developed and compared with the simplifications that are known from the moiré principle. The theory is tested using a circular plate, uniformly loaded and clamped at the circumference. 相似文献
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Gratings have been widely accepted as practical and effective deformation carriers/sensors and are commonly used in many deformation measurement methods. Since the deformation measurement sensitivity is directly proportional to the grating frequency, and the measurement accuracy is strongly affected by the grating quality. Thus, it is crucial to prepare an appropriate grating on the specimen surface that is to be measured. Over the past few decades, an increasing number of grating fabrication methods have been developed, including holographic photolithography, electron beam lithography, focused ion beam etching, nanoimprinting, soft lithography, and others. Although substantial literature regarding grating fabrication can be found, a comprehensive review is still necessary to promote the application of these methods. This review introduces the technical details and characteristics of recently developed grating fabrication methods and provides suggestions of which grating fabrication methods to use in correspondence with different deformation measurement methods. Emphasis is placed on the introduction of grating fabrication processes and the quality and applicability of the resulting gratings. 相似文献