提出了一种粒子尺度信息提取方法, 通过将傅里叶叠层思想应用到粒子尺度信息提取中实现了比λ/NA更高的空间分辨率。在传统的傅里叶叠层成像系统中, 采用一个二维LED阵列作为光源以获得不同角度的照明, 通过扫描阵列中的所有LED, 获取一系列低分辨图像, 然后利用这些低分辨图像生成一幅高分辨图像。为了减少所需的低分辨图像幅数, 进一步提出了选择型照明傅里叶叠层成像提取粒子尺度信息的方法, 通过分布在一个圆周上的LED提取粒子尺度信息, 根据分辨率极限公式给出了圆周半径的选择方法。仿真结果结果表明提出的方法在不损失精度的前提下能够大幅度减少需要的低分辨图像幅数。

A method, which can extract the particle size information with a resolution beyond λ/NA, was proposed. This was achieved by applying Fourier ptychographic(FP) ideas to the present problem. In a typical FP imaging platform, a 2D LED array was used as light sources for angle-varied illuminations, a series of low-resolution images were taken by a full sequential scan of the array of LEDs, and the data were then combined to produce a high-resolution image. Here, the particle size information was extracted by turning on each single LED on a circle, whose radius was chosen according to an expression for the resolution limit. The simulated results show that the proposed method can reduce the total number of images without loss of reliability in the results, and the total number of images can be further reduced by optimizing the aperture overlapping rate.