Laser-driven inertial confi nement fusion (laser fusion) has been investigated with large-scale high-power lasers since 1960’s. Progress of new laser technology, such as multi-beam irradiation system, frequency conversion, beam smoothing, and chirped pulse amplifi cation, signifi cantly accelerated the laser fusion research. FIREX project to demonstrate efficient heating of the compressed fuel to the ignition temperature with Fast Ignition scheme is underway in Osaka. Attempt to achieve high-density implosion and ignition is also underway on NIF in the US, and the first demonstration of the thermo nuclear ignition and burning of controlled nuclear fusion will be demonstrated soon by laser fusion. Laser fusion demo power plants are expected to appear in 2020‒2030. Laser drivers with large output energy, high effi ciency, high repetition rate, long life, and low cost will be required for laser fusion reactors.
