Fuel pellets for use in laser fusion reactors

Purpose: To improve fuel pellets for use in laser fusion reactors thereby attain uniform irradiation and conversion of laser wavelength to shorter wavelength. Constitution: In a fuel pellet having multilayered spherical structure, spherical shell layers are disposed to the outside of a fuel portion situated at the core of a pellet, in which the spherical layers comprise a permeation layer transmitting light at the wave-length of shorter than 0.1 μm, a reflection layer disposed to the outerside of the permeation layer having one or more laser energy permeating windows and attached at its inner surface with material for reflecting laser beams and a layer disposed between the permeation layer and the reflection layer that contains material which is gaseous at normal temperature. Since laser beams are irradiated only to the window permeating the laser energy, the number of laser beams can be decreased to simplify the structure of the reactor. While repeating reflection, the energy is absorbed into gases and gases formed into plasmas generate light with shorter wavelength which are passed through the permeation layer and absorbed in the fuel spheres. The inside of the pellet is not heated and can be compressed stably, to attain uniform irradiation. (Kamimura, M.)