Collimator for high takeoff angle energy dispersive spectroscopy (EDS) detectors

The collimator of claim 7 wherein the collimator extension section has a length which is selected such that when the collimator is placed in an EDS detector system the distal end of the collimator extension section extends through an aperture in an upper pole piece to at least 0.1 millimeters below a bottom of the pole piece.

A collimator for energy dispersive spectroscopy (EDS) detectors, comprising:

• (a) a collimator base section having a base end adapted to be attached rigidly to an EDS detector tube, a distal end, a base section aperture extending from the base end of the collimator base section to the distal end of the collimator base section, and a flange formed on the distal end of the collimator base section which extends inward toward the axis of the base section aperture;
• and
• (b) a collimator extension section having a base end, a distal end which is narrower than the base end of the collimator extension section such that the collimator extension section is attachable to the collimator base section by extending the distal end of the collimator extension section through the base section aperture at the distal end of the collimator base section such that the base end of the collimator extension section is within the base section aperture and the collimator extension section is held in the collimator base section by the flange, and an extension section aperture extending from the base end of the collimator extension section to the distal end of the collimator extension section such that the extension section aperture and the base section aperture are aligned when the collimator extension section is attached to the collimator base section.

An improved electron microscope system for performing energy dispersive spectroscopy including an electron beam source, an upper pole piece having an aperture therein through which the electron beam may pass, a sample specimen holder area located below the aperture in the upper pole piece, an EDS detector tube, and an EDS detector mounted in the EDS detector tube, the improvement comprising:

• a collimator having a base end attached rigidly to the EDS detector tube, a distal end extending through the aperture in the upper pole piece to below a bottom of the pole piece, and a collimator aperture extending from the base end of the collimator to the distal end of the collimator such that the collimator aperture is aligned with the EDS detector.