Abstract: The present invention relates to a charged particle device with improved detection scheme. The device has a charged particle source providing a beam of primary charged particles; a first unit for providing a potential; a second unit for providing a potential; and a center unit positioned between the first unit and the second unit. The center unit is capable of providing a potential different from the potential of the first and the second unit for decelerating the primary charged particles to a first low energy and for accelerating the primary charged particles to a second high energy. Therein, the first unit and/or the second unit is a detector for detecting secondary electrons released at a specimen.