Introduction to the Issue on Advanced Signal Processing in Microscopy and Cell Imaging

Microscopy imaging, including fluorescence microscopy and electron microscopy, has a prominent role in life science and medical research. During the past two decades, biological imaging has undergone a revolution by way of the development of new microscopy techniques that allow the visualization of tissues, cells, proteins and macromolecular structures at all levels of resolution, physiological states, chemical composition and dynamic analysis. Thanks to recent advances in optics, digital sensing technologies and labeling probes (i.e., XFP—Colored Fluorescence Protein), we can now visualize subcellular components and organelles at the scale of a few nanometers to several hundreds of nanometers. As a result, fluorescent microscopy has become the workhorse of modern biology. Further technological advances include structured and coherent light sources, faster and more sensitive detectors, smaller and more specific molecular probes and automation processes for image acquisition. Additionally, there is a push towards multimodal imaging in order to gather complementary information such as the concentration of fluorophores at various wavelengths and the refractive index of a given sample (phase imaging).