Most of these require additional equipment in addition to a basic compound microscope. Under a compound microscope conidia appear ovoid in shape. The use of a compound microscope is needed for accurate identification. Cells were first seen in 17th century Europe with the invention of the compound microscope. Galileo Galilei is also sometimes cited as a compound microscope inventor. When looking underneath a compound microscope, you will be able to see the ascospores. By 1624, Galileo had used a compound microscope. His was a single lens simple microscope, rather than a compound microscope. Other historians point to the Dutch innovator Cornelis Drebbel with his 1621 compound microscope. In 1621 Drebbel had a compound microscope with two convex lenses. A compound microscope also enables more advanced illumination setups, such as phase contrast.