Although glass objects for artistic and utilitarian purposes were present during Roman times and earlier, optical metrology was practically non-existent prior to the emergence of spectacles. Glasses to improve human vision first appeared in Italy around 1280, and some progress in understanding fundamentals of optics was made after that date and during the renaissance. It was not, however, until 1608 with the invention of the telescope in Holland, that the long evolutionary development of optical metrology as a specific scientific discipline began in earnest. The Author traces classical methods of optical metrology from the 17th century telescope era up to the mid-20th century, with emphasis on optical systems for reconnaissance, surveillance, and astronomy. The Author’s hands-on experience in quantitative optical metrology began shortly after World War II with military surplus optics, followed by the construction and testing of numerous telescopes between 6 and 16-inches aperture during the 1950s. The 1960s brought extensive testing and evaluation of lenses at the optical laboratories at Wright-Patterson AFB, Ohio and elsewhere, continuing through the early days of laser metrology in the mid-late 1960s and afterward. This paper presents examples of testing lenses and cameras for USAF, DoD, and NASA to include those used in the Gemini and Apollo Programs. Special emphasis is placed on classic resolving power testing with large collimators and special test cameras using aerial photographic films. Closing comments will stress impacts for later-era digital sensors, high-speed computers, and metrological lasers.
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