early 1970s, when better lasers appeared. Funding for fusion research was stimulated by energy crises produced rapid gains in performance, and inertial designs were soon reaching the same sort of "below break-even" conditions of the best MCF systems. LLNL was, in particular, well funded and started a laser fusion development program. Their Janus laser started operation in 1974, and validated the approach of using Nd:glass lasers for high power devices. Focusing problems were explored in the Long path and Cyclops lasers, which led to the larger Argus laser. None of these were intended to be practical devices, but they increased confidence that the approach was valid. It was then believed that a much larger device of the Cyclops type could both compress and heat targets, leading to ignition. This misconception was based on extrapolation of the fusion yields seen from experiments utilizing the so-called "exploding pusher" fuel capsule. During the late 1970s and early 1980s the estimates for laser energy on target needed to achieve ignition doubled almost yearly as plasma instabilities and laser-plasma energy coupling loss modes were increasingly understood. The realization that exploding pusher target designs and single-digit kilojoule (kJ) laser irradiation intensities would never scale to high yields led to the effort to increase laser energies to the 100 kJ level in the ultraviolet band and to the production of advanced ablator and cryogenic DT ice target designs. Shiva and Nova One of the earliest large scale attempts at an ICF driver design was the Shiva laser, a 20-beam neodymium doped glass laser system at LLNL that started operation in 1978. Shiva was a "proof of concept" design intended to demonstrate compression of fusion fuel capsules to many times the liquid density of hydrogen. In this, Shiva succeeded, reaching 100 times the liquid density of deuterium. However, due to the laser's coupling with hot electrons, premature heating of the dense plasma was problematic and fusion yields were low. This failure to efficiently heat the compressed plasma pointed to the use of optical frequency multipliers as a solution that would frequency triple the infrared light from the laser into the ultraviolet at 351 nm. Schemes to efficiently triple the frequency of laser light discovered at the Laboratory for Laser Energetics in 1980 was experimented with in the 24 beam OMEGA laser and the NOVETTE laser, which was followed by the Nova laser design with 10 times Shiva's energy,