| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a foil trap in which each foil is prevented from being deformed by debris and an exchange frequency can be reduced, and a light source device employing the same.SOLUTION: In the foil trap which is disposed between collector mirrors each for collecting light emitted from a light source and captures debris from the light source, a plurality of foils are divided into a plurality of inside foils 52 which are disposed in an inside area parted by an internal ring 53 and an intermediate ring 54, and a plurality of outside foils 51 which are disposed in an outside area parted by the intermediate ring 54 and an external ring 55. Since damage caused by debris is more obvious in the inside foils than in the outside foils, the inside foils 52 are made thicker and the outside foils 51 are made relatively thinner than the inside foils so as to be as thick as foils which are conventionally used. Thus, damage on the inside foils 52 is reduced and light transmissivity can be prevented from being reduced.</p> |
