You may not know it, but there’s light that you can’t see. Besides the beautiful hues of the rainbow, from deep red to bright yellow to green and violet, there’s more light… and it doesn’t have any colour. Light is made up of an electromagnetic field, you see. That field moves in waves. If the peaks of those waves are too close together or too far apart, the human eye can’t make sense of them. Light whose peaks are too close together is called ultraviolet, and too far apart is called infrared. But even though you can’t see them, ultraviolet and infrared light are very useful. Scientists in the past have used ultraviolet light (the short one) to make better microscopes: to see things that are too small to see with regular light. Not so long ago they also used it to make very small things like computer circuits and the DVD’s you use to watch movies. But now, scientists at the Max-Planck Institute of Biochemistry in Martinsried, Germany have found a way to use infrared light (the long one) to look at things even smaller than with ultraviolet light. They’ve invented something called a “near-field microscope” — you can see how it works in the picture to the left. It’s just about the world’s most acute “optical sensing” technology ever. Dr. Rainer Hillebrand told DW’s Erik Campano exactly what you’re seeing in that diagram of the fabulous new near-field microscope.