Juan Roget

Juan Roget or Joan Roget (Angoulême, France c.1550 - Aveyron, France? c.1617-1624) was a spectacle maker in Girona, Catalonia, Spain who has been cited as a possible inventor of the telescope.

Juan Roget was born in Angoulême, France, and was the son of a cloth carder Ramón Roget. According to the Catalan optometrist and amateur historian Simon de Gualleuma, Juan was married to Joana of Malaville, France, and migrated to the city of Girona, Principality of Catalonia, Spain, where he worked as a master spectacle maker.

His brother Pere Roget, also a spectacle maker, settled in Barcelona by the Plaça del Blat and two of Pere's children also became master spectacle makers. The register of deaths of Rodez Cathedral in Aveyron list the death of Joana Roget as August 7, 1614. There is no register record of Juan Roget's death but the register book for deaths between 1617 and 1624 is missing, giving him a probable death date between those two dates.

A 1959 research paper by Simon de Guilleuma claimed that evidence he had uncovered pointed to the French born spectacle maker, Juan Roget, as the inventor of the telescope before Hans Lipperhey's patent application for the same device in October 1608 and that Dutch spectacle makers had copied Roget's device. Guilleuma referenced a book published in 1618, "Telescopium: sive ars perficiendi novum illud Galilaei visorium instrumentum ad sydera in tres partes divisa" (Telescope, or a performance of the art and means to Galileos's new vision of the stars, in three volumes) by Italian author Hieronymi Sirturi Mediolanensis (aka Girolamo Sirtori of Milan) in which the author describes a 1609 meeting with a "withered old" spectacle maker in Girona named "Roget" who claimed to have invented the telescope. Simon de Guilleuma researched the register of deaths of Rodez Cathedral in Aveyron and found that there was a "Roget" family of spectacle makers, leading him to conclude that the spectacle maker in the Sirtori story was Juan Roget. The claim was further investigated by historian Nick Pelling in an October 2008 History Today magazine article, in which he attempted to reconstruct the movements of Lipperhey and the other Dutch inventors before the patent application, and found that a connection with Roget was plausible. Other evidence that the historians think could help establish priority was a 10 April 1593 will from Barcelona where a man bequeathed a "long eyeglass decorated with brass" to his wife, although this could also describe a magnifying glass.