| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a voltage cutting-off device simple in structure and capable of providing stable switching operation. SOLUTION: This voltage cutting-off device is structured by series-connecting three gaps 1 to 3, and equipped with a laser light source 16 for outputting laser light 18 for triggering and a multi-focus convex lens 30a provided in the lowest-stage gap electrode 11. The multi-focus convex lens 30a has three focal zones different in focal distances from each other, receives the laser light 18 from the laser light source 16, and causes the laser light 18 to pass through the respective focal zones to converge it on the respective gaps 1 to 3. More specifically, the laser light 18 is converged on surfaces of light-receiving electrodes 12c, 13c of the middle-stage gap electrodes 12, 13, and on a surface of the highest-stage gap electrode 14.</p> |
