Early 16th-Century Optical Microscope

Timeline

1. c. 1580–1590Middelburg · ZeelandIn the late 16th century, Dutch spectacle manufacturing flourished; the magnifying principle of combining convex and concave lenses was repeatedly experimented with in the workshops of spectacle makers in Middelburg, Delft, and elsewhere, laying the craft foundation for the birth of the compound microscope.
2. c. 1590–1595Middelburg · ZeelandAccording to oral accounts from later members of the Janssen family, the Janssens made a compound microscope prototype with a sliding brass tube, a convex lens objective, and a concave lens eyepiece, achieving 3–9× magnification, mounted on a tripod for observing small objects.
3. c. 1600–1630Low Countries · Low CountriesThe concept of the compound microscope spread in the Netherlands and neighboring regions; contemporaneous spectacle makers such as Lippershey are also listed by some scholars as possible inventors. Because no early physical specimens survive, priority of invention remains uncertain, but the 1590s is the chronologically accepted anchor point in scholarship.