3-D glasses were glasses usually made out of cardboard, and two transparent colored wax paper lenses, usually red and blue respectively, for use in watching three-dimensional films. These were made to increase business of movies after the rise of television caused many customers to switch to television instead. Thousands of movie houses closed up shop in the 1950s. Although many 3-D movies of the 1950s were low budget "creature features", one noteworthy film was shot in 3-D, House of Wax, which was medium-budget and intended for a more mainstream audience. Part of the reason for the lukewarm reception of Alfred Hitchcock's The Birds was that Hitchcock filmed it using special three-dimensional cameras, but by the time the film was released, 3-D was largely out of style.
Managers of movie theatres would distribute the glasses to customers before the film, then collect them after the customers departed. Men who worked as theatre attendants during this era often stated this was the worst part of their job, the distribution and recollection of the 3-D glasses, and it was easy for punks to simply walk away with the glasses without returning them, which is most likely how 3-D acquired the glasses for his trademark nickname.
The 3-D movie fad largely passed by the 1960s, when by that era there was significant improvement in cinematography to attract moviegoers. It should be noted that by 2015, 3-D films made a comeback, and were advanced enough that glasses were not needed to enjoy the show.