An optical-path calibration module having a multi-faceted outer sidewall enclosing to define an internal cavity, wherein parts of the multi-faceted outer sidewall define a first light inlet, a second light inlet, and a first light outlet respectively, and a first light-splitting device is disposed in the internal cavity; wherein, the first light inlet is configured to receive or block a calibration beam from an external light source; the second light inlet is configured to receive a target-light-source beam; the first light outlet is configured to output the target-light-source beam and/or the calibration beam; and the first light-splitting device is configured to guide the calibration beam from the first light inlet to the first light outlet for output, and/or guide the target-light-source beam from the second light inlet to the first light outlet for output; wherein optical-path calibration module further comprises: an adjustable mirror mount, wherein, the adjustable mirror mount comprises a light-splitting-device bracket, a base for fixing the light-splitting-device bracket, a cover plate elastically connected with the base, a movable rotating shaft, and a threaded pair, and the adjustable mirror mount is disposed in the internal cavity; the light-splitting-device bracket has a side surface and a bottom surface, the side surface of the light-splitting-device bracket is a hollow inclined surface, the first light-splitting device is fixed to the hollow inclined surface by a pressing piece, the bottom surface of the light-splitting-device bracket is fixed to the cover plate, and the bottom surface of the light-splitting-device bracket defines a light transmission-hole; the cover plate defines a light through-hole at a center of the cover plate, the cover plate is elastically connected with the base at the bottom of the cover plate, and the movable rotating shaft and the threaded pair are elastically disposed between the cover plate and the base; the base defines the first light inlet for light to pass through at a center of the base, and the first light inlet, the light through-hole of the cover plate, and the light transmission-hole of the light-splitting-device bracket are interconnected; a recess defined between the base and the cover plate is configured to clamp the movable rotating shaft, and a through-hole defined at a side of the recess is configured to receive the threaded pair; and the threaded pair extends through the through-hole to abut against the cover plate at a top end of the threaded pair, and to be fixed with a lower surface of the base at a lower end of the threaded pair through a cap for the threaded pair, and the cap for the threaded pair beyond the lower surface of the base is rotatable to adjust a distance between the base and the cover plate. the first light inlet is configured to receive or block a calibration beam from an external light source; the second light inlet is configured to receive a target-light-source beam; the first light outlet is configured to output the target-light-source beam and/or the calibration beam; and the first light-splitting device is configured to guide the calibration beam from the first light inlet to the first light outlet for output, and/or guide the target-light-source beam from the second light inlet to the first light outlet for output; an adjustable mirror mount, wherein, the adjustable mirror mount comprises a light-splitting-device bracket, a base for fixing the light-splitting-device bracket, a cover plate elastically connected with the base, a movable rotating shaft, and a threaded pair, and the adjustable mirror mount is disposed in the internal cavity; the light-splitting-device bracket has a side surface and a bottom surface, the side surface of the light-splitting-device bracket is a hollow inclined surface, the first light-splitting device is fixed to the hollow inclined surface by a pressing piece, the bottom surface of the light-splitting-device bracket is fixed to the cover plate, and the bottom surface of the light-splitting-device bracket defines a light transmission-hole; the cover plate defines a light through-hole at a center of the cover plate, the cover plate is elastically connected with the base at the bottom of the cover plate, and the movable rotating shaft and the threaded pair are elastically disposed between the cover plate and the base; the base defines the first light inlet for light to pass through at a center of the base, and the first light inlet, the light through-hole of the cover plate, and the light transmission-hole of the light-splitting-device bracket are interconnected; a recess defined between the base and the cover plate is configured to clamp the movable rotating shaft, and a through-hole defined at a side of the recess is configured to receive the threaded pair; and the threaded pair extends through the through-hole to abut against the cover plate at a top end of the threaded pair, and to be fixed with a lower surface of the base at a lower end of the threaded pair through a cap for the threaded pair, and the cap for the threaded pair beyond the lower surface of the base is rotatable to adjust a distance between the base and the cover plate.