| 摘要 |
PURPOSE:To obtain a discharge tube able to stop generation of metal vapor without using buffer gas by providing a housing part of a metal vapor supply with a connecting-through part which connects through an internal space of the discharge tube and an internal space of the housing part while providing a switching means switching this connecting-through part by the operation from outside the discharge tube. CONSTITUTION:The inside of a discharge tube 1 is provided with a housing part 14 housing a metal vapor source. This housing part 14 consists of a fixed first cylindrical body 15 and the second cylindrical body 16 free-slidably inserted into this first cylindrical body 15. When laser oscillation is to be stopped, a projected end 19 operates to shift the second cylindrical body 16 to the first cylindrical body 15 and to relatively shift the connecting-through holes 15a and 16a so as to close connection-through of an internal space of the discharge tube 1 and an internal space of the second cylindrical body 16. This closure stops the supply of metal vapor to the internal space of the discharge tube 1 so as to stop oscillation of laser light. |
