| 摘要 |
PROBLEM TO BE SOLVED: To improve robustness to fluctuations of characteristics of an ion source such as mass dependence and plasma state change by sufficiently increasing an opening size in continuous ion flow direction of a pulser ion ejection port than an opening size in continuous ion flow direction of a detector for detecting an ion. SOLUTION: An opening size E in continuous ion flow direction (x direction) of an ion ejection port 22 of a pulser 20 is increased, and a difference in x- direction speed Vx is absorbed by a width in x direction of a packet-shaped ions 24 to be ejected in y direction. If the x-direction speed vx is reduced by a change in characteristics of an ion source with an ion from point B being incident on a detector 30, an ion 24 emitted from a point B will not be incident on a detector 30. Since an ion ejection port 22 is large, an ion emitted from a point C is incident on the detector 39, and sensitivity is kept unchanged. With respect to mass dependence generated for every ion mass, since efficiency of the ion incident on the detector 30 is not changed, the efficiency can be significantly improved. |
