Viewlex was a manufacturer of slide projectors and associated audio-visual media devices:
They seem to have reached their prime in the 1960's, when they introduced some innovative products, including the "Slide Scriber":
|Popular Science, June 1962|
|Toledo Blade, March 24, 1962|
"The device, which uses no liquids or chemicals, will produce spirit masters, projection transparencies, offset masters, regular office copies and also laminate. It is designed for use in schools, offices and factories and measures 16 by 13.5 inches. It will retail for about $200."
In 1966 came "Viewlex Super Sound," the first 8-mm cine projector designed to add sound to this format of film. This was also called the M format or Maurer 8 format, named for the engineer who designed it, John A. Maurer.
Starting in the late 1960's, the company entered the planetarium technology arena with its Apollo projector.
The "Viewlex" trademark was first filed in 1958, but cancelled in 2000. Their "Apollo" trademark expired in 1992. Apparently, the firm declared bankruptcy sometime in the 1990's.