PROBLEM TO BE SOLVED: To confirm soundness of a laser ion source.SOLUTION: A laser ion source according to an embodiment includes: a vacuum container 1 which is evacuated to produce vacuum and has an incident window 1a formed therein for accepting incoming laser light L a target 2 which is arranged in the vacuum container 1 and generates ions when being irradiated with the laser light L a transport tube 7 which serves as an ion-beam extraction part for extracting an ion beam to the outside of the vacuum container 1 by electrostatically bringing out ions from the vacuum container 1 and an ion beam current measurement instrument 8 for measuring an ion beam current value after being extracted to the outside of the vacuum container.SELECTED DRAWING: Figure 4
