Nicolas Hartsoeker

Nicolaas Hartsoeker (26 March 1656, Gouda – 10 December 1725, Utrecht) was a Dutch mathematician and physicist who invented the screw-barrel simple microscopecirca 1694.

He was the son of Anna van der Meij and Christiaan Hartsoeker (1626–1683), a Remonstrant minister in Moordrecht near Gouda. His father took the family to Alkmaar in 1661 and finally to Rotterdam in 1669. Nicolaas started to make a living as a lens maker in Rotterdam, and was instructed in optics by Antonie van Leeuwenhoek. In 1674, he and a fellow student, assisted by Van Leeuwenhoek, were the first to observe semen, a situation that would later lead to a priority dispute between Hartsoeker and Leeuwenhoek over the discovery of spermatozoids.

In 1677, Hartsoeker met Christiaan Huygens and initiated him in the making of lenses. In June 1678, Hartsoeker accompanied, in the role of an assistant, Huygens on a trip to Paris, where they made a great impression with their microscopes. Huygens failed to mention Hartsoeker even once in a subsequent publication in France however, leading to a fall-out between the two.

Hartsoeker returned to Rotterdam, where his parents still lived and where he married Elisabeth Vettekeucken in October 1680. His business as an instrument maker and wine merchant failed and, after the death of his father in August 1683, he moved his family in 1684 to Paris, where he made instruments for the Paris observatory and the academy. Hartsoeker also came up with contrivances for aiming very large aerial telescopes originally popularized by Huygens. He remained there until 1698.

...
Wikipedia