Reflectance imaging for visualization of unlabelled structures using Nikon A 1 and N-SIM

Interference Reflectance Microscopy (IRM) was the initial application of reflected light imaging1. IRM involves the formation of an image from signal that is generated by light interacting at the boundary of substrates with differing refractive indices (RI). Since this original application, a variety of different configurations have emerged leading to the generation of images based on RI mismatches that are naturally occurring throughout cell and tissues samples. However, contrast can also be artificially induced by the introduction of materials with high RI and optical density, analogous to fluorescent labelling.