Calibration method and distance measurement device thereof based on phase measurement of double-wavelength laser tube

A calibration method based on phase measurement of double-wavelength laser tube, wherein:

• the said method includes the following steps:
• Step 1 is the formation of external optical path:
• the light-emitting device of the system emitting the first light-wave through the first filter to the measured object, the said light-wave focused by the optical device after reflecting back by the measured object, then being received by the receiving device and as a measured external optical path of the system;
• The said light-wave through the a first filter, while some light-wave energy is reflected to the receiving device by the filter or other reflective film and filter by the second filter;
• Step 2 is the formation of internal optical path:
• the light-emitting device of the system emitting the second light-wave filter by the first filter and the said filter or other reflective film reflected to the receiving device and through the second filter received by the said receiving device directly, wherein the light-wave through the second filter will be the base reference internal optical path of the phase measurement system;
• Step 3:
• when Steps 1 and 2 is working, the first light-wave and the second lightwave obtained by the light-emitting device switching successively, the said receiving device proceed phase comparison with the internal, external optical path received successively is made, and outputting the phase signal which eliminates the base reference.