LED array microscopy system correction method with comprehensive error parameters optimized by phase smoothing criterion

Abstract

LED array microscopy is a novel computational imaging technique that can achieve two-dimensional (2D) phase imaging and three-dimensional (3D) refractive index imaging with both high resolution and a large field of view. Although its experimental setup is simple, the errors caused by LED array position and light source central wavelength obviously decrease the quality of reconstructed results. To solve this problem, comprehensive error parameters optimized by the phase smoothing criterion are put forward in this paper. The central wavelength error and 3D misalignment model with six freedom degree errors of LED array are considered as the comprehensive error parameters when the spatial positional and optical features of arbitrarily placed LED array are unknown. Phase smoothing criterion is also introduced to the cost function for optimizing comprehensive error parameters to improve the convergence results. Compared with current system correction methods, the simulation and experimental results show that the proposed method in this paper has the best reconstruction accuracy, which can be well applied to an LED array microscope system with unknown positional and optical features of the LED array.

Alternating projection combined with fast gradient projection (FGP-AP) method for intensity-only measurement optical diffraction tomography in LED array microscopy

“…Green LEDs, with a central wavelength of 520 confirmed by a spectrometer, are employed for illumination. The systematic errors caused by LED array can seriously affect 3D reconstruction results, so before the start of 3D reconstruction algorithm, our previous work is used to correct the multi-parameter errors in the system [ 35 ]. The axial imaging range during the reconstruction process is also set to 100 , and the number of sample layers in the z-direction is determined to be 24 by , and .…”