Zacharias Janssen himself and his father Hans were 2 Dutch spectacle makers who in 1590 invented the compound microscope and they first did it by experimenting on the lenses made of glass which was though first invented in the 1st Century AD and they did it by placing several of these lenses in a tube and made a very important discovery and that discovery was that objects near the end of the tube appeared to be greatly enlarged much larger than any simple magnifying glass could achieve by itself.
though the earliest version of the microscope itself existed since before Zacharias Janssen and his Father Hans but was though simple and were only magnifying glasses which had a power of 6X – 10X and the thing that was very common and interesting to look at was fleas and other tiny insects. These early magnifiers were hence called flea glasses.
(The father of Microscopy itself was Anthony Leeuwenhoek)
Though we do not know the complete and full life of Zacharias Janssen but we do know that he died in 1632 (sometimes 1638).
We don’t know the full life of Zacharias Janssen though Janssen’s life was documented by the many investigations on the subject before the Second World War. Many of the Middelburg archives were destroyed by a bombing of Middelburg on May 17 1940 during the Nazi invasion of the Netherlands. Without these earlier studies very little would be known of Janssen’s life at all since all original files were lost in the fires following the bombardment.