CALIBRATION METHOD AND DISTANCE MEASUREMENT DEVICE THEREOF BASED ON PHASE MEASUREMENT OF DOUBLE-WAVELENGTH LASER TUBE

A calibration method and a distance measurement device thereof based on phase measurement of a double-wavelength laser tube. The method comprises the following steps: step 1, a first wavelength light-wave is transmitted to a target to be measured through a first light filter from a light wave transmitting device during forming an external light path, the light-wave is modulated from a high frequency oscillating signal (S101); step 2, a second wavelength light-wave is transmitted to the receiving device through a second light filter from the light wave transmitting device during forming an internal light path, as an internal light path signal of a basic reference, the second light-wave is generated from the high frequency oscillating signal (S102); step 3, the receiving device compares phases of the two sequentially received light-waves, and output a phase signal eliminated the base reference (S103).