Capturing high-quality electron-counted diffraction at low dose with the Metro camera

Gatan instrument used

The camera Metro^® enables low-dose imaging and diffraction at low kV via real-time electron counting with a simple user interface.

Background

Selected area electron diffraction (SAED) patterns present a challenge for any recording medium. The variation of intensity from the bright center spot to faint high-frequency ones can be extreme, spanning multiple orders of magnitude and resulting in saturation and undetected spots. Accurately capturing SAED patterns can be quite difficult for a scintillator-based detector, as it requires high dynamic range, high sensitivity, and low noise (high signal-to-noise ratio (SNR)). The Metro camera uses direct detection electron counting and is optimized for diffraction imaging with a background free of noise and other imaging artifacts; it does not require a beam stop and, compared to scintillator-based cameras like the OneView^®, can detect high-intensity and faint diffraction spots with a superior SNR and sharper diffraction peaks.