2. Cathode ray tubes

The first electronic image projection systems to appear in the 1970s used cathode ray tube (CRT) technology. Their use increased in the 1980s with the advent of consumer rear projection. Today, given their size and weight, and the difficulty of installing and adjusting them on the customer's premises, there are hardly any tube-based products left in the world of front projection, except in very specific applications (military, etc.). These have been supplanted by more compact, user-friendly technologies such as liquid crystal display (LCD) (§ 3