* Single - molecule fluorescence imaging by total internal reflection fluorescence microscopy ( IUPAC Technical Report )

Total internal reflection fluorescence (TIRF) is a popular illumination technique in microscopy, with many applications in cell and molecular biology and biophysics. The chief advantage of the technique is the high contrast that can be achieved by restricting fluorescent excitation to a thin layer. We summarise the optical theory needed to understand the technique and various aspects required for a practical implementation of it, including the merits of different TIRF geometries. Finally, we discuss a variety of applications including super-resolution microscopy and high-throughput DNA sequencing technologies.