in 1657-58. He possibly met Christiaan Huygens during this time, and may have learned about the magic lantern from him. Correspondence between them is known from 1667. From 1664 until 1670, Walgensten demonstrated the magic lantern in Paris (1664), Lyon (1665), Rome (1665-1666), and Copenhagen (1670).

He "sold such lanterns to different Italian princes in such an amount that they now are almost everyday items in Rome", according to Athanasius Kircher in 1671. In 1670, Walgensten projected an image of Death at the court of King Frederick III of Denmark.