The current lighting mechanisms enable globe lights, with no supported method to create directional / spot lights. This has resulted in 1.60 and 1.62 mod / other content creators are creating linkages based on undocumented class functionality to circumvent gaps in the ARMA 3 API.
Request is to expose the existing class capabilities to establish a spotlight through ARMA scripting commands.
Tilion confirmed the functionality exists in the engine in July 2013:
https://forums.bistudio.com/topic/146430-reflector-lights/#entry2372239
Example community requests for this functionality:
https://forums.bistudio.com/topic/169214-scripted-searchlights/
https://forums.bistudio.com/topic/146430-reflector-lights/
https://forums.bistudio.com/topic/165609-directional-light-possible/