Late 1600s – Dutch scientist Antonie van Leeuwenhoek constructed a microscope with a single spherical lens. It magnified up to ×275. 1800s - the optical quality of lenses increased and ...

He shows us how he restores an oil painting from the 1800s. This includes looking at it under a microscope, performing X-rays on the painting, filling in areas where paint has chipped off ...