1590s, "one who forms a project or projects," agent noun in Latin form from project (v.). In the sense of "camera with a light source for throwing an image on a screen" it is attested from 1884.
by 1953, said to have been in use in radio broadcast jargon since early 1940s, American English, possibly from Yiddish glitsh "a slip," from glitshn "to slip," from German glitschen, and related gleiten "to glide" (see glide (v.)). Perhaps directly from German. Apparently it began as technical jargon among radio and television engineers, but was popularized and given a broader meaning c. 1962 by the U.S. space program.
No more a-c power line "glitches" (horizontal-bar interference)—because camera filaments are operated from a separate d-c source. [RCA ad for the TK-11A studio television camera in Broadcasting Telecasting magazine, Jan. 12, 1953]
All you get today is "glitch" wherever splicing occurs. "Glitch" is slang for the "momentary jiggle" that occurs at the editing point if the sync pulses don't match exactly in the splice. [Sponsor, Volume 13, June 20, 1959]
Buck Rogers thought it up more than 25 years ago, and Bell System has been working on it here for 15 years. Now it's here.
It is called Picturephone, and it is a small television camera and receiver that allows telephone users to gaze into the features of the person they are talking to.
Whether this really is a boon to mankind remains to be seen.
["Picturephones Are On The Way," St. Louis Post-Dispatch, Aug. 28, 1970]
late 13c., "something which strikes with a loud, sharp noise," agent noun from clap (v.). Meaning "tongue of a bell" is from late 14c. Old English had clipur. Meaning "hinged board snapped in front of a camera at the start of filming to synchronize picture and sound" is from 1940.
Clappering.—It is still necessary to warn clergymen and churchwardens against allowing the lazy and pernicious practice of 'clappering,' i.e. tying the bell-rope to the clapper, and pulling it instead of the bell. More bells have been cracked in that way than by all other causes together, and there is not the least excuse for it .... [Sir Edmund Beckett, "A Rudimentary Treatise on Clocks and Watches and Bells," London, 1883]