Wave-optical calibration of a light-field fluorescence microscopy

In light-field microscopy, a single point emitter gives rise to a complex diffraction pattern, which varies with the position of the emitter in object space. In order to use deconvolution-based wave-optical reconstruction schemes for light-field imaging systems, established methods rely on theoretical estimation of such diffraction patterns. In this paper we propose a novel method for direct experimental estimation of the light-field point spread function. Our approach relies on a modified reversed micro-Hartmann test to acquire a composite light-field point spread function of several thousand point emitters in the object plane simultaneously. By using fiducial markers and a custom image processing algorithm we separate the contributions of individual point emitters directly in raw light-field images and allow the construction of the forward imaging process without any prior assumption about the optical system required. The constructed forward imaging model can finally be applied in the 3D-deconvolution based wave-optical reconstruction scheme.