A new ionization gauge of the 'cascade static lens (CSL) gauge, which
has high sensitivity (S) and operates with weak emission current (I(e)
), was studied. In the gauge, apertured electrodes forming a cascade e
lectrostatic lens system are installed between the cathode and the ion
collector, allowing the electrons to oscillate many times between the
cathode and the ion collector under the focusing effect of the lenses
. Suitable electrode potentials were studied by computer simulation. T
he experimental value of S = 22. 1 Pa-1 (2870 torr-1) with I(e) = 4 mu
A was obtained rather easily, and the linearity was confirmed in the m
easured pressure region (8 x 10(-8) Pa approximately 1.5 x 10(-5) Pa).