高清晰度粒子全息再现像的获取方法

Methods for obtaining high-quality reconstructed image of particles

为了掌握同轴粒子场全息诊断中再现系统参量,如放大率、光强、图像采集设备及背景光等因素对粒子再现像质量的影响,开展了系列的实验研究。由实验可知,调节再现光的强度,使背景光强尽量接近CCD阈值下限,可以得到背景噪声均匀、再现清晰度高的图像;而对于粒径在20μm以下的较小粒子及具有一定放大率的再现系统,则需要通过适当增加再现光强度来得到高清晰度的图像;保持实验室的暗背景环境对图像采集是非常有利的。结果表明,此方法可以在粒子场全息再现过程中获得高清晰度粒子再现像。

In order to understand the effect of the system factors, such as light intensity, magnification, CCD and background, on the reconstructed image of different diameter particles in the process of holographic reconstruction, a series of experiments were performed. The experimental results showed that, by adjusting the light intensity and making the background light intensity closed to the lower limit of CCD threshold,images with smoothing background and high definition were acquired. For particles with diameter less than 20μm and a reconstruction system with a certain magnification, a little higher intensity of reconstruction light was needed for ideal images. It was favorable for image keeping the experimental environment dark. Results show that high quality particle images can be obtained by means of the above methods in the process of particle holographic reconstruction.