Patent ID: 7391019
Filing Date: 2008-06-24
Classification: H01J

Abstract:
1. An ion source of the type which comprises an ionization chamber and an adjacent low-pressure region, the ion source comprising a capillary tube having an axial bore for supporting fluid communication between the ionization chamber and the adjacent low-pressure region, the axial bore of the capillary tube being substantially concentrically aligned with an orifice of a skimmer positioned to sample ions emitted from the capillary tube, the ion source further comprising a blocking element that is disposed in an aligned facing arrangement with the axial bore of the capillary tube and on an opposite side of the orifice relative to the capillary tube, wherein droplets or particles flowing through the axial bore of the capillary tube pass through the orifice of the skimmer and to the blocking element, wherein the blocking element comprises a tube having a first end facing the orifice for receiving the droplets or particles passing therethrough.