A Lekolite (often abbreviated to Leko) is a brand of ellipsoidal reflector spotlight (ERS) used in stage lighting. Introduced in 1933 [1], it was developed by Joseph Levy and Edward Kook, founders of Century Lighting, which eventually became a part of the Strand Lighting Corporation. The instrument was widely used in theatre and entertainment venues into the 1990s, particularly in the USA, and modern fixtures, such as the Electronic Theatre Controls Source 4, are direct descendants of Levy's and Kook's design.
Century Lighting founders and the instrument's inventors, Joseph Levy and Edward Kook, combined the first two letters of their own last names and called the unit "Leko." Rival lighting company, Kliegl Brothers, released their own Elipsoidial Reflector Spotlight that same year, calling it "Klieglight". It is unclear which company was first to develop the new technology, but both had developed the technology earlier and had to wait until a lamp was developed by GE that would work in the new fixture. The Leko nickname became widely used to refer to any ERS. Strand lighting has begun to use the 'Lekolite' name again.