光学学报, 2017, 37 (6): 0611002, 网络出版: 2017-06-08
无衍射光束成像系统携带信息的研究
Study on the Image Information Carried by the Non-Diffraction Beam Imaging System
成像系统 无衍射光束 离散傅里叶变换 图像信息 imaging systems non-diffraction beam discrete Fourier transform image information
摘要
研究了无衍射光束成像系统对图像信息的携带情况。在入射的平面波中加入图像信息, 基于基尔霍夫衍射公式和菲涅耳衍射公式的角谱理论, 使用离散傅里叶方法描述图像经轴棱锥后在观察面的光强分布, 对图像面进行数据抽样并引入色散公式; 将离散傅里叶公式导入Matlab并设置参数模拟, 得到不同位置处的光强图。实验中, 利用蓝光LED发出光束经扩束后入射到含有信息的菲林片和轴棱锥上, 实验参数与数值模拟一致, 利用CCD观察结果, 对比模拟结果可知: 菲林片上的图像经轴棱锥后, 在传输100 mm内, 可以完整观察到图像信息, 图像大小会随距离的增加而减小。实验结果与数值模拟十分吻合。
Abstract
The status of image information carried by the non-diffraction beam imaging system is proposed. Based on the Kirchhoff diffraction formula and Fresnel diffraction formula’s angular spectrum theory, the intensity distribution of receiving screen is described using the discrete Fourier method, with image information in the incident plane wave. After adding the dispersion formula and data sampling, a discrete Fourier formula is derived, the related parameters are set and simulated with Matlab software, and the light intensity figures at different positions are obtained. In the experiment, the blue LED is incident on information film and axicon after expanding, and consistent with the numerical simulations. The results observed by CCD and compared to simulation show that the image can be observed completely when the transmission distance within 100 mm and becomes smaller as the distance increases. The experimental results are in fair agreement with the numerical simulation.
何艳林, 徐浩博, 吴逢铁. 无衍射光束成像系统携带信息的研究[J]. 光学学报, 2017, 37(6): 0611002. He Yanlin, Xu Haobo, Wu Fengtie. Study on the Image Information Carried by the Non-Diffraction Beam Imaging System[J]. Acta Optica Sinica, 2017, 37(6): 0611002.