Fast spectral-spatial EPR imaging with modulated gradient and simultaneous field scan

Spectral spatial EPR imaging with modulated gradient and simultaneous field scan (MOSS) was investigated with regard to its spectral and spatial resolution and its total measuring time. The gradient coil system is used to overlap the fast field scan with a modulated field gradient. The complete image was measured in 64 s, utilizing a gradient-modulation frequency of 66 s⁻¹. This technique does not require image reconstruction. The influence of different modulation functions (cosine and triangular) and of a partial blanking of the applied cosine-modulated signal on the spectral-spatial image is discussed. The partial-blanking method is most suitable for fast imaging and best image quality.