Editing Light pen (section)

== History ==

{{anchor|Lightgun}}The first light pen, at this time still called "light gun", was created around 1951–1955<!-- to be narrowed down better --> as part of the [[Whirlwind I]] project at [[MIT]], where it was used to select discrete symbols on the screen,<ref name="Everett_1980"/><ref name="Roch_1996"/><ref name="Carlson_2009"/><ref name="CDE_2009"/> and later at the [[Semi-Automatic Ground Environment|SAGE]] project, where it was used for tactical real-time-control of a radar-networked airspace.<ref name="Roch_1996"/>

One of the first more widely deployed uses was in the Situation Display consoles of the [[AN/FSQ-7]] for military airspace surveillance. This is not very surprising, given its relationship with the Whirlwind projects. See [[Semi-Automatic Ground Environment]] for more details.

During the 1960s, light pens were common on graphics terminals such as the [[IBM 2250]] and were also available for the [[IBM 3270]] text-only terminal.

The first nonlinear editor, the [[CMX 600]] was controlled by a light pen, where operator clicked symbols superimposed on edited footage.

Light pen usage was expanded in the early 1980s to music workstations such as the [[Fairlight CMI]] and personal computers such as the [[BBC Micro]] and [[Holborn 9100]]. [[IBM PC]]-compatible [[Monochrome Display Adapter|MDA]] (only early versions),<ref name="Kosmic_2023"/> [[Color Graphics Adapter|CGA]],<ref name="Kosmic_2023"/> [[Hercules Graphics Card|HGC]]<ref name="Elliott_2020_MDA"/> (including [[HGC+]]<ref name="Elliott_2012_HGCPlus"/> and [[InColor]]<ref name="Elliott_2012_InColor"/>) and some [[Enhanced Graphics Adapter|EGA]] graphics cards also featured a connector compatible with a light pen, as did early Tandy 1000 computers,<ref group="notes">For example, the Tandy 1000 SX has a [[DE-9]] light pen connector on the rear panel; on the later-introduced Tandy 1000 TX, this light pen interface has been replaced with a serial port using the same connector in the same location.</ref> the [[Thomson MO5]] computer family, the [[Amiga]],<ref name="Amiga"/> [[Atari 8-bit]], [[:Category:Commodore 8-bit family|Commodore 8-bit]], some [[MSX]] computers<ref name="MSX_2019"/> and [[Amstrad PCW]] home computers. For the MSX computers, [[Sanyo]] produced a light pen interface cartridge.<ref name="Sanyo"/>

Because the user was required to hold their arm in front of the screen for long periods of time (potentially causing "[[Touchscreen#"Gorilla arm"|gorilla arm]]") or to use a desk that tilts the monitor, the light pen fell out of use as a general-purpose input device.{{citation needed|date=January 2012}} Light pen was also perceived as working well only on displays with low persistence, which tend to [[Flicker (screen)|flicker]].<ref name="Norton_1983"/>