1) Display technology 
A monoscope was a special form of video camera tube which displayed a single still video image. The image was built into the tube, hence the name. The tube resembled a small cathode ray tube (CRT). Monoscopes were used beginning in the 1950s to generate TV test patterns and station logos. This type of test card generation system was technologicall...
an electron-beam tube capable of providing a picture signal derived from a fixed given image on an electrode inside the tube
a cathode-ray tube that provides a signal of a fixed pattern for testing television equipment.