Device and method for energy and angle-resolved electron spectroscopy

The invention concerns devices and methods for imaging of a beam of particles composed of charged particles with a certain energy and angle distribution on a detector, and a spectrometer, especially for electron diffraction measurements, with energy and angle resolution. A device for imaging a beam of particles composed of charged particles with a certain energy and angle distribution on a detector device using a device, including a deflection unit with at least one deceleration lens provided for forming essentially parallel particle paths in the particle beam, whose reciprocal distances correspond to the angle distribution of the particles, and a filtering unit, which is located between the deflection unit and the detector facility, whereby the filtering unit may be biased with a potential for formation of a braking field and is adapted to be energy-selectively permeable for the particles, on the sample side before the deflection unit, an entry window in the form of an axial-symmetrical staged aperture or an entry grid is located, which is electrically separated from the deflection unit and at ground potential.