ICF research turned to using an "optical frequency multiplier" to convert the incoming IR light into the ultraviolet at about 351 nm, a technique that was well known at the time but was not efficient enough to be worthwhile. Research on the GDL laser at the Laboratory for Laser Energetics in 1980 first achieved efficient frequency tripling techniques which were then used next (for the first time at LLNL) on Shiva's successor, the Novette laser. Every laser-driven ICF system after Shiva has used this technique.