Light Field Microscopy Combined with Super-resolution Techniques

Abstract

This study introduces a light field microscopy (LFM) in which a microlens array is employed for spatial and angular sampling of light from an object through an objective lens in a wide-field optical microscopy. The LFM has expanded depth of field and digital refocusing ability for 3D measurement. However, it has a critical drawback that spatial resolution is limited by spatial sampling determined by diameter of each microlens. Typically each microlens have several sub-millimeter diameter, hence the cutoff frequency in the diffraction limited imaging system spatial exceeds spatial sampling frequency in the LFM images. As one of the solutions for this problem, resolution improvement based on sub-pixel shift multi-image processing was proposed. Then the experimental apparatus to verify the proposed method was developed. The resulting image (see Figure. 1) exhibited higher spatial resolution than that of a sub-aperture image obtained by a typical light field microscopy. Furthermore, a different approach towards the super-resolution of the LFM, which employs Fourier Ptychography a kind of computational imaging technique, will be introduced.