The invention discloses a device and a method for detecting movement errors of a working platform in
multiple degrees of freedom. Reflected light is reflected onto a three-surface reflector fixed on the working platform through a light path regulation reflector, returns to the light path regulation reflector after being reflected by the three-surface reflector in sequence, is reflected onto a second light splitting piece, enters a beam expanding mirror after being reflected by the second light splitting piece, and is projected onto a
detector. Transmission light enters the beam expanding mirror after being transmitted by the second light splitting piece and is projected onto the
detector. Two beams of light generate interference on the
detector, and measurement on deflection and movement displacement of the working platform can be achieved by regulating shapes of interference fringes and measuring
phase displacement. By means of the device and the method for detecting movement errors of the working platform, synchronous and real-time measurement on an angle of oscillation, an angle of
pitch and axial movement displacement of the working platform can be performed, real-time compensation is performed according to the measurement result to eliminate effect caused by movement errors, and
measurement precision and manufacturing precision can be improved. The angle measurement ranges from +3rad to -3mrad, and measurement requirements of the working platform can be met.