An imaging method is provided for a modular mixed reality (MR) device having an MR calculation module, an MR optical path module and an MR posture module. The MR calculation module is configured to adjust display content according to data from the MR posture module. The MR optical path module comprises a virtual-image optical path and a mixed optical path. A semi-transparent semi-reflective mirror is provided in the mixed optical path. One surface of the mirror is a real-image introduction surface facing a real environment, while the other is a virtual-image introduction surface facing the virtual-image optical path. Virtual-image light is reflected by the virtual-image introduction surface onto an observation end and mixed with real environment light transmitted to the observation end by the real-image introduction surface to form a mixed reality image.