CL Detectors

 Cathodoluminescence (CL) is the emission of photons of characteristic wavelengths in the visible spectrum which is caused by the interaction of the electron beam with a sample. CL is a powerful structural and compositional analysis technique for materials that can reveal valuable information that cannot be obtained through SE, BSE or EDX. Such information includes zonal composition, lattice structure, superimposed strain or damage to the structure of the material. SEM-based CL imaging achieves much better resolution compared to optical CL microscopes.

TESCAN CL detectors

Thanks to their outstanding sensitivity, TESCAN CL detectors achieve high signal-to-noise ratio even at low accelerating voltages, which makes imaging of fine details of sample structure possible. Furthermore, the signal collection efficiency is uniform over the full field of view (FOV). Using the TESCAN Wide Field Optics™ technology, a FOV up to 35mm (width) without any signal decrease towards the image outer border can be achieved.

Panchromatic CL Detectors:

TESCAN has developed two types of panchromatic detectors with different wavelenght range of detected light:
  • 350 nm – 650 nm for detecting mainly visible and near UV light. This version can be either stand-alone or exchangeable CL/BSE detector.
  • 185 nm – 850 nm for detecting UV, visible and near IR light.

Rainbow CL detector

The Rainbow CL detector enables simultaneous panchromatic and live colour CL imaging in the spectral range of 350- 850 nm. The CL signal is split into red, green and blue components which are acquired simultaneously and they are electronically composed into a live colour image of the scanned area.


All TESCAN CL detectors are fully integrated in the microscopes control software. They can be retracted from their working position whenever not in use.

CL Detectors
CL Detector

Related Application Notes

Cathodoluminescence analysis of zircons
Zircons (ZrSiO4) are ubiquitous in the crust of Earth and are a common accessory to trace mineral constituent of most granite and felsic igneous rocks. Zircons have low solubility in most melt and fluid compositions and can survive geological processes such as erosion, transport, or high-grade metamorphism. This makes zircon one of the most important minerals for geochronology. Different types of zircon domains are identified by CL imaging and U-Pb dating is then used to determine ages of different zones within the crystal. This helps to recognize various geological processes recorded during the history of the grain.
pdf – 1.8 MB
Cathodoluminescence imaging of mineralogical samples
Cathodoluminescence (CL) - light emission produced by electron beam - reveals information about material composition and structure that often cannot be obtained by other methods. In geosciences, optical cathodoluminescence became a standard technique. With the development of scanning electron microscopes, SEM-CL is gaining in popularity. In comparison with optical CL microscopes, where the sample is irradiated with stationary unfocussed electron beam, SEM-based CL imaging achieves much better resolution and it can be combined in situ with other analytical methods.
pdf – 3.9 MB