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In this paper, we use for the first time the ray-tracing method combined with the HFSS software to analyze lens antennas. HFSS is a very popular commercial tool that can provide very accurate results for the simulation of antennas. However, because of limitations on computational resources, it is hard to apply to solving large electromagnetic problems. In this paper, HFSS is used to simulate the fields of the feed part of a lens antenna. The ray tracing method is adopted for the lens part. This treatment makes the combined method feasible for solving large lens antennas. In using the ray-tracing method, cubicspline interpolation is exploited to fit the face of the lens and to solve for the derivatives at each point on the curved surface. Newton's method is applied to find the intercept between the ray and the curved surface. The numerical method proposed in this paper is very suitable for the analysis of dielectric lens antennas with arbitrary feeds and lens shapes. The validity of the idea is demonstrated by comparing the simulation results of this new method with those from using CST (Computer Simulation Technology) software. Very good agreement is achieved. 相似文献
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Hu Tiantian Zeng Chunmei Rui Congshan Hong Yang Ma Suodong 《红外与激光工程》2021,50(2):20200183-1-20200183-8
为了提高透镜的散热能力,设计了一种新型全内反射(TIR)透镜,该透镜的出射面中央为自由曲面菲涅耳面。采用斯涅尔定律和全反射定律分别求解TIR透镜折射部分和反射部分自由曲面的面形。同时,采用一种菲涅耳透镜的普适设计方法将折射部分自由曲面转变成菲涅耳面。通过蒙特卡洛光线追迹模拟自由曲面菲涅耳TIR透镜的照明效果,结果显示:当光源尺寸为2 mm×2 mm时,其远场照度均匀性为82%,光效为96.6%,透镜质量为21.94 g。与未加菲涅耳面的TIR透镜相比,带自由曲面菲涅耳面的TIR透镜在光效仅下降2%,在照度均匀性未变的情况下,透镜质量减少了约20%。这说明对TIR透镜的自由曲面出射面进行菲涅耳化可明显地缩小透镜的体积和质量,缩短光线在透镜内部的光程,因此可有效提高透镜的散热效率和使用寿命,同时保持良好的照明效果。 相似文献
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旋转轴对称LED均匀照明系统设计方法 总被引:2,自引:1,他引:1
基于边缘光学理论,提出了一种应用于LED照明的光学系统设计方法,分别实现基于透镜和反射器的LED均匀照明光学系统,可在一特定距离的目标面上形成均匀圆形光斑。采用基于蒙特卡罗法的光线追迹软件对两种光学系统进行模拟仿真,结果显示,目标面上光斑的均匀度优于85%,系统效率高于90%。 相似文献
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为设计单个非球面扩束(缩束)透镜,由光线折射定律矢量形式和对非球面折射特性的理论分析,提出了一种设计单个非球面扩束(缩束)透镜的新方法全面学习策略的粒子群算法,并用此方法设计出了线度小于170 mm缩束14.16倍的单个非球面缩束透镜,用光线追迹方法模拟了缩束或扩束过程。模拟结果表明,单个非球面透镜可以起到缩束或者扩束作用,全面学习策略的粒子群算法可用于非球面缩束透镜的设计。单个非球面透镜作为扩束镜使扩束系统结构大大简化,大大提高了出射光斑的均匀性。 相似文献
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A high-frequency method for the three-dimensional analysis of integrated dielectric lens antennas is presented. This method consists on improving the physical optics (PO) currents on the lens surface by modifying, via suitable transition functions, the spreading factor of those rays from the source point which arrive at the lens-air interface close to the critical angle of incidence. Invoking the locality principle of the high-frequency phenomena, the method uses the rigorous canonical solution of the semi-infinite dielectric space locally tangent at the lens surface. A uniform asymptotic evaluation of this canonical solution is provided with the introduction of a new transition function for the TM case. The present formulation provides significant correction from the PO currents of an elliptical lens, with a consequent improvement of the radiation pattern prediction, testified by comparisons with results from a full-wave analysis. 相似文献
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倒锥透镜型光纤端由特殊技术加工而成。本文给出了这种光纤端的折射率分布。借助于光纤在球面上的折射公式及光线传输方程,分析了这种新型单模光纤端的光学传递性质。在近轴近似下,给出了这种光纤端的光学传递矩阵。 相似文献
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The paraxial lens theory cannot directly be applied to the cathode trajectories inside the gun. This inconvenience makes the interpretation of cathode trajectories difficult since one cannot use the physical concepts familiar in the paraxial lens theory, such as focal length and magnification factor. We have proposed the canonical mapping transformation (CMT) to describe the electron trajectories inside the gun by relating the ray conditions on the cathode surface to those in the crossover plane. The method takes as variables the distance along the surface and the sine of the ray angle with respect to the surface normal to define ray conditions. It has been shown that the CMT can be characterized by a small number of optical parameters. One of the parameters is the 'electron gun focal length', an extension of the image side focal length in the paraxial lens theory. The crossover size of a triode gun can be calculated from the electron gun focal length and the initial transverse energy spread. The calculation predicts the dependence of the crossover size on the grid voltage due to the change in the electron gun focal length. The prediction is compared with the measurement and shows good agreement with it. Since the CMT optical parameters can be calculated from the representative trajectories only and as they predict practically all the necessary source properties of guns, the CMT can be used as a practical tool in the designing of various types of electron guns. 相似文献
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根据柱透镜单元光传输原理,提出了一种非均匀宽度视差图条纹及其在合成图像中非均匀排列的方法,该方法可以减少立体图像串扰,增加各个视点接收到的对应视差图的信息量,使观看到的自由立体图像更加清晰。此外,置于LCD屏前的柱透镜光栅条纹方向与屏表面的坐标轴倾斜角度的改变会导致图像在竖直和水平方向分辨率的变化。与光线追迹测量分辨率损失的ASAP软件模拟法不同,本文以解析法分析了光栅条纹倾斜角度对竖直和水平方向分辨率损失的影响,计算结果对柱透镜光栅自由立体显示器的设计有一定的参考性。 相似文献
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传统自由曲面LED配光透镜由于在自由曲面求解时存在误差,往往导致最终配光效果不理想。为了进一步提高配光效果,提出基于非球面内表面调制的自由曲面配光透镜设计方法,采用非球面内表面对自由曲面的求解误差进行补偿,有效地减小了自由曲面的误差对配光效果的影响。通过对自由曲面求解误差进行定量计算,建立用于补偿误差的非球面内表面设计方法,形成了基于非球面内表面调制的自由曲面配光透镜的完整的设计思路。将这一方法应用于矩形照明区域的LED路灯透镜设计之中,相对于传统自由曲面配光透镜,照度均匀度由0.66提高到0.73,能量利用率从47.3%提高到63.2%。 相似文献
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New calculations for coupling laser diode to multimode fiber 总被引:1,自引:0,他引:1
A simple and useful method is presented for calculating characteristics of a laser diode to a multimode fiber coupling. Attenuation of higher order modes in multimode fiber is introduced into ray tracing. Maximum coupling efficiencies and misalignment tolerances of optical circuit components are computed for utilization of a relatively large spherical lens and combination of two relatively large spherical lenses. It is clarified that attenuation of higher order modes strongly affects both maximum coupling efficiency and misalignment tolerances. Agreement between theoretical and experimental coupling characteristics is greatly improved compared with the case for conventional ray tracing. 相似文献
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光场相机作为一种新型的成像系统,可以直接从一次曝光的图像中得到三维信息。为了能够更充分有效地利用光场数据包含的角度和位置信息,完成更加精准的场景深度计算,从而提升光场相机的三维重建的精度,需要实现精确的几何建模,并精确标定其模型参数。该方法从薄透镜模型和小孔成像模型出发,将主透镜建模为薄透镜模型,将微透镜建模为小孔成像模型,结合光场相机双平面模型,将每个提取到的特征点与其在三维空间中的射线建立联系,详细解释了内参矩阵中每个参数的物理意义,以及标定过程中初值确定的过程,并在镜头径向畸变模型的基础上进一步应用了相机镜头的切向畸变模型以及基于射线重投影误差的非线性优化方法,改进了光场相机的标定方法。实验显示,该方法的RMS射线重投影误差为0.332 mm,与经典的Dansereau标定方法相比,进行非线性优化后得到的射线重投影误差精度提升了8%。该方法详细分析的场景点与特定像素索引的推导过程对光场相机的标定具有重要的研究意义,为光场相机光学模型的建立与初始化标定奠定了基础。 相似文献
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为了设计单个椭球面缩束(扩束)透镜,采用全面学习策略的粒子群算法作为设计方法,依据光线折射定律矢量形式所表征的椭球面折射特性进行了理论分析,得到了用全面学习策略的粒子群优化算法设计单个椭球面缩束(扩束)透镜的适应度数据公式,设计出了线度小于170mm缩束14.16倍的单个椭球面缩束透镜,并用光线追迹方法模拟了缩束或扩束过程。结果表明,单个椭球面透镜可以起到缩束或者扩束作用,全面学习策略的粒子群算法可用于椭球面缩束透镜的设计。这一结果对于简化扩(缩)束系统结构、设计出适应于不同要求的单个扩(缩)束透镜是有帮助的。 相似文献
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Diffraction fields in the focal space of some lens is investigated by using ray tracing and Stratton-Chu formulas. Two formulas are used. One is surface integration formula, and for another a line integration is added. Comparison of two calculation results is given. It is shown that for hyperbolic lens two calculations results are same and for extended hemi-ellipsoidal lens there are a lilt difference between them. 相似文献
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在综合研究已有的各种复合物镜(如移动物镜、变轴物镜和摆动物镜等)的基础上,本文对复合物镜的一般理论进行了探讨,推导了普遍化计算公式,并提出新的复合物镜(弯曲物镜)系统。采用解析函数近似表示系统场分布,对弯曲物镜系统象差进行了理论分析,并设计出一个实际系统。数值计算结果给出该系统在55mm2扫描场内,束孔径角5mrad和能散2.5eV下,最大彗差0.005m,横向色差0.001m。 相似文献