Tukey窗切趾全息图用于粒子场在焦位置测量的实验研究

提出采用能量透射率较大、频谱旁瓣峰值和旁瓣衰减斜率较小的Tukey窗对粒子场数字全息图进行切趾处理.分析了在焦位置测量和Tukey窗切趾粒子场数字全息图的原理.实验记录了附着于玻璃板表面的微小单层粒子场的数字全息图,采用Tukey窗对其切趾后进行数值再现.实验结果表明,全息图切趾后的再现像中已不存在黑白相间的干涉条纹,衬比度增强,再现粒子像更清晰,处于边缘区域的再现粒子像几乎被切趾孔径所淹没;随着窗函数切趾参量的逐渐增大,可更准确地确定单层粒子场的在焦位置,提高粒子场在焦位置的测量精度.

Application of Digital Hologram Apodization Using Tukey-Window for Particle In-Focus Position Measurement

A apodization method with Tukey-window function for digital hologram of particle-field was presented, whose energy transmission is relatively high and the sidelobe peak is relatively low as well as the sidelobe roll-off rate.The principles of in-focus position measurement and digital hologram apodization using Tukey-window for particle were analyzed.The digital holograms of little monolayer particle-field attached on glass surface were recorded,and the apodized holograms adopting Tukey window were reconstructed.The experimental results show that the reconstructed images after digital holograms apodization do not have black-and-white interference fringe, increase contrast and have more clear particle image.The reconstructed particle image located in the fringe field is nearly submerged by the apodized aperture.With increasing the apodization parameter of the window function,the more accurate position of the particles in-focus can be gained,and the measurement precision of particle in-focus position is improved.