John F. Gregory (1927–November 14, 2009) was an American optical engineer and a popularizer of amateur telescope making.
In the 1960s he worked for Barnes Engineering Company in Stamford, Connecticut, where he designed and tested lenses used in the infrared and ultraviolet.
Gregory's article included detailed optical specifications as well as shop techniques and testing algorithms.
He was a frequent attendee at meetings of amateur astronomers, including Stellafane and the Riverside Telescope Makers Conference.
The car his wife Carolyn was driving in Lakeway, Texas, was struck by a pickup truck around 8:20 am.