Magnetically-focused electrono-graphic cameras have been under development at the Naval Research Laboratory for use in far-ultraviolet imagery and spectrography, primarily in astronomical and optical-geophysical observations from sounding rockets and space vehicles. Most of this work has been with cameras incorporating internal optics of the Schmidt or wide-field all-reflecting types. These cameras have flown on a number of sounding rocket missions for stellar ultraviolet studies, and are planned for addition-al missions on sounding rockets and space vehicles in the near future. More recently, we have begun development of electronographic spectro-graphs incorporating an internal concave grating, operating at normal or grazing incidence. We also are developing electronographic image tubes of the conventional end-window-photo-cathode type, for far-ultraviolet imagery at the focus of a large space telescope, with image formats up to 120 mm in diameter. Our work so far has been with air-exposable alkalihalide photocathodes sensitive in the wavelength range below 2100 A. We are presently under-taking to extend the utility of the electronographic Schmidt and end-window devices toward longer wave-lengths, by the use of appropriate photocathode materials.
George R. Carruthers,
Chet B. Opal,
E. O. Hulburt,
"Electronographic Cameras For Space Astronomy", Proc. SPIE 0028, Instrumentation in Astronomy I, (1 September 1972); doi: 10.1117/12.953539; https://doi.org/10.1117/12.953539