We propose a passive self injected scheme for the generation of short pulse trains from various pulsed lasers. In this scheme a single subnanosecond pulse is generated from a short cavity seeding laser. The pulse is then returned to the same gain medium and amplified regeneratively until the gain is quenched completely. An ultraviolet subnanosecond pulse train is directly and passively generated from a solid state laser medium (Ce 3+ ∶LuLiF 4) pumped by a standard 10 nsec laser.