Seems to be well known in the field of microscopy.

This article discusses the topic. Sounds to me like there is an algorithm involved to compute and "reverse" the effects of diffraction.

From the article:

"The most significant source of blur is diffraction, and an image whose resolution is limited only by blur is considered to be diffraction-limited. This represents an intrinsic limit of any imaging system and is the determining factor in assessing the resolution limit of an optical system. Optical theory proposes sophisticated models of blur, which can be applied, with the assistance of modern high-speed computers, to digital images captured in the optical microscope. This is the basis for deconvolution."

Edit: And:

"[...] because blur is a function of the microscope optical system (principally the objective), it can be modeled with relative simplicity. Such a model renders it possible to reverse the blurring process mathematically, and deconvolution employs this model to reverse or remove blur."