An important invention of the Renaissance was the microscope. Invented in 1590, the microscope was a major help in other scientific discoveries. The microscope uses two different lenses to bend light and enlarge images. Therefore, a person could see things that were too tiny to observe with the naked eye. In 1660, the microscope was used to study bacteria for the first time. A microscope at that time could enlarge images 270 times their normal size.