| 摘要 |
In a discharge tube (1) of the present invention, a filler gas is composed of a mixture of inert gas and hydrogen gas and an airtight cylinder (10) in which the filler gas is enclosed in an airtight manner is provided. A pair of first and second discharge electrodes (22,24) are opposed to each other within an internal space of the airtight cylinder (10), so that an electric discharge is generated between discharging surfaces of the first and second discharge electrodes (22,24). In the discharge tube (1), a concentration of the hydrogen gas in the filler gas is set in a range from 20 percent by volume to 80 percent by volume. |
