Our technical glossary on the topic of coating thickness measurement, material analysis and the characterization of surfaces.
- Definition: Aperture
The use of an Aperture (collimator) restricts the cross-section of the primary X-ray beam, creating a measurement spot with a pre-defined size, which allows precise adjustment of the size and shape of the X-ray beam to the specimen geometry. Depending on the measurement system, individual fixed apertures or exchangeable multi-apertures are employed.
For measurements on very small objects such as the bond areas on leadframes, the Aperture is substituted by a special X-ray optics with mirrors or poly-capillaries, which simultaneously provides for both a very small measurement spot and high excitation intensity.