Abstract: This paper suggests a new a scheme for a laser aecelerator according to the principle of geometrie opties. A lens with special non-spherical surface is used to focus the laser rays onto the axis. The phase of these rays can be continuously adjusted as the electrons move forward along the axia, so that the constant acceleration of electrons lis achieved. Because the focusing factor lis very large, the electrons can obtain a very high energy gain on a very short length of travel. When the electrons are decelerated, it is possible to realize a free electron laser. Finally, we prove that it is impossible to use a focusing mirror in this scheme.