This spectrophotometer is being used to measure the cathode photoresponse and quantum efficiency of image tubes in the UV to near IR region (from 200 nm to 900 nm), with an external lock-in amplifier synchronized to the Cary's internal optical chopper. Good day-to-day stability has been routinely verified by using an image tube calibrated by a photometrics laboratory. Fully automatic operation is achieved via a Varian personal computer and IEEE-488 communication. Hard copy printout is both numerical and graphical.
W. E. Flynt, W. E. Flynt,
"Photoresponse Measurements Using A Modified Cary/Varian 2390 Spectrophotometer And Computer", Proc. SPIE 1072, Image Intensification, (14 April 1989); doi: 10.1117/12.952550; https://doi.org/10.1117/12.952550