| 摘要 |
PROBLEM TO BE SOLVED: To provide a quadrupole mass spectrometer suppressing the noise caused by the light generated at an area to be measured or at an ion source, with few sensitivity loss. SOLUTION: For the quadrupole mass spectrometer, impressing high frequency voltage to a quadrupole electrode 10 composed of 4 pieces of rod-shaped electrodes arranged parallel with each other, emitting only the ion having specified mass, ionized at an ionizing part, from an outlet of the quadrupole electrode 10, and detecting the emitted ion by an ion detector 11 located at the back side of an outlet part as a current, a light receiving surface 16 of the ion detector 11 is formed into ring-shape, and the center axis of the light receiving surface 16 and the axis of the quadrupole electrode 10 are arranged so as to coincide with each other, and an electric field, guiding the ion to the part located between the outlet of the quadrupole electrode 10 and the light receiving surface 16 of the ion detector 11, is formed. |
