The Collaborative International Dictionary of English v.0.48:

Photochromoscope \Pho`to*chro"mo*scope\, n. [Photo- + Gr.
   chrw^ma color + -scope.]
   1. A device for giving shifting effects of color to a
      photograph. The unmounted print, made translucent, is
      illuminated from behind with colored light.
      [Webster 1913 Suppl.]

   2. A combination of three optical lanterns for projecting
      objects on a screen in the colors of nature. The images of
      three partial photographs taken through color screens
      (red, green, and blue, respectively) are superimposed.
      Each image is given its own primary color, and these
      colors blend and reproduce the colors of the object.
      [Webster 1913 Suppl.]