Abstract: An electromagnetic micro positioner, e.g. for use in fibre optics, is operated by a ceramic piston (8) mounted within a ceramic cylinder (5). The piston (8) is moved by a permanent magnet (9) and an electromagnetic circuit (1/2). By changing the coil (2) polarity the piston (8) will either be attracted or repelled to its top or bottom position. In particular the core (1), capable of polarity reversal, has a magnetic remanence by means of which the movable piston (8) is fixable in one of the two predefined positions when the coil (2) is not energized.