phase measurement calibrating method , calibrating device and ranging device based on the liquid crystal shutter principle are disclosed . a light wave is emitted by a light wave emitter to a tested target through a first liquid crystal shutter . the light wave is reflected and returned from the tested target to be focused by an optical device , and is received by a receiver . the received light wave is used as the external light path beam of the measurement system . while the light wave is passing through the first liquid crystal shutter , a part of the light wave is reflected by the first liquid , crystal shutter to pass through a second liquid crystal shutter . the light wave passing through the second liquid crystal shutter is received directly by the receiver and used as the internal light path beam for fundamental reference of the system phase measurement . the first liquid crystal shutter and the second liquid crystal shutter are switched respectively while the system operates so that the receiver is utilized for comparing phases of the internal light path beam and the external light path beam received respectively to output phase shift for eliminating a fundamental reference . the calibrating method achieves phase compensation and calibration , increases measurement accuracy of a laser ranging operation , and enhances ranging stability of the system .