Shown above is a scanned optical diagram of the Cary™ 14
from Instructions for Cary Recording Spectrophotometer Model 14, circa 1953.

The arrows on the optical diagram trace the path of the ultraviolet and visible radiation through the instrument. Radiation from the deuterium or tungsten lamp is directed to the monochromator entrance slit D by appropriate lenses and mirrors. From mirror E it travels to prism F where it is refracted, then to mirror G which reflects it to variable width intermediate slit H. Mirror I reflects the radiation to grating J and from there the monochromatic beam is directed to mirror K and exits the monochromator through slit L. Semicircular mirror O, driven by motor Q, chops the beam at 30 Hz and alternately sends half the beam to the reference and half to the sample. Elements V, V¹, W, and W¹ pass the separated beams to the phototube. The light pulses of the two beams are out of phase with each other so that the phototube receives light from only one beam at a time.

The photomultiplier for UV/Vis work is shown at X and the NIR detector for 700-2600 nm is shown at Y. The handle, shown at Z, is automated in the Olis Cary™ 14 & 17 models.