DEBRIS SHIELD

摘要

PROBLEM TO BE SOLVED: To make it possible to irradiate a target with laser beams stably for a long time by installing a debris shield between a laser-beam entry window and a target so that the shield can move in the direction crossing the optical axis of the laser beams. ;SOLUTION: Excited laser beams 7 are linearly condensed 2, penetrates a laser-beam entry window 10, a debris shield 6 and a through-hole 50 and irradiates a target 3. The irradiation of the laser beams generates an X-ray laser 8 from laser plasma generated on the surface of the target 3. A shield plate 5 and a shield 6 block out the debris which is generated and scattered at the same time to prevent it from adhering to the entry window to. Though some debris passes through the through-hole 50 and adheres to the shield 6, most of it is shielded 5. As a result, most of the surface area of the shield 6 can avoid the adhesion of the debris. Since a wind-up roll 61 is driven to move the shield 6, moreover, the surface with adherents is off a light path and a new surface is located on it. Then, the laser beams 7 emitted subsequently irradiate the target 3 smoothly. This makes it possible to irradiate the target 3 stably for a long time.;COPYRIGHT: (C)1998,JPO