Which display technology used electron beams to produce images before modern digital screens?

The Cathode Ray Tube (CRT) is the correct answer because it was one of the first display technologies to utilize electron beams to create images. In CRTs, a focused beam of electrons is directed onto a phosphorescent screen, which glows when struck by the electrons, effectively producing images. This technology was the standard for television and computer monitors for many decades until the advent of more modern technologies.

Other display technologies such as Liquid Crystal Displays (LCD), Light Emitting Diodes (LED), and Plasma Displays operate fundamentally differently. LCDs use liquid crystals manipulated by electric fields to control light and produce images, while LEDs use light-emitting diodes for illumination. Plasma displays utilize small cells of gas that emit light when ionized. Each of these technologies represents a significant advancement that eliminated the need for the electron beam mechanism, which was the hallmark of CRTs.