Galileo calls his compound microscope with a concave and a convex lens the occhiolino, or little eye. The magnifying device is a gateway drug—he soon starts experimenting with telescopes.

Then, a maker paired convex and concave lenses together, in an approach similar to how telescopes were made, creating the first compound microscope. By 1625, the term “microscope” had been ...

The properties of concave and convex lenses were first described ... Jansen and his son Zacharias as inventors of the first compound microscope in 1595. Their microscope had two lenses combined ...

These lenses are either convex - converging light, which magnifies an object, or concave, where light diverges making an object smaller. However, this new lens is 40 nm thin on a flat glass surface .