Angle-Resolved

Overview

In the angle-resolved cathodoluminescence (ARCL) mode, the direction in which a photon is emitted is determined. An objective lens or, more commonly, a collection mirror projects an image of the emitted light onto a pixelated detector, e.g., a camera. When an appropriate optical system is used, each pixel in the captured image corresponds to a unique emission direction from the specimen. The raw image is typically transformed into polar coordinates for display and interpretation.

The result of an angle-resolved measurement contains no wavelength or polarization information unless additional dispersion filtering is used (e.g., wavelength- and angle-resolved mode).

Angle-filtered information may be captured using an iris or a pinhole to select a specific (range of) angle(s). However, this particular acquisition mode's low resolution and highly serial nature have limited its usefulness.