ABSTRACT
Fluorescence microscopy was first introduced at the very beginning of the 20th century, and August Kohler was one of the pioneers. From the beginning of the twentieth century, great technological improvements were made in the fundamentally ancient technique of making glass filters. The driving forces were partly scientific, but the rapidly expanding popularity of photography also played a major part. From Ploem’s time up until the turn of the century the common light sources used in fluorescence microscopy were sealed high-pressure arc lamps. The recent development of high-intensity and short-wavelength light-emitting diodes has provided another alternative for fluorescence illuminators. Research-level fluorescence microscopes these days are often computer controlled, which tends to be great for the experienced user who can navigate the subtleties of the software. Computer control is the future, no doubt about it, but to get the best out of a microscope one must understand what is actually happening in the hardware.
