Measurer calibration method based on phase triangulation for measurements in limited volume with refraction of optical signals

The paper presents a method for calibration of a three-dimensional geometry measurement system based on the phase triangulation for measurements in the conditions of limited volume with optical signals refraction. The calibration algorithm implements calibration procedures directly in the measurement volume in the presence of all the limiting objects that cause optical signals refraction. The method is universal for various conditions of limiting volume with optical signals refraction. The developed calibration method was tested in the case the limiting volume in the form of a plexiglass tube with the transverse size of 200 mm ´ 200 mm and the wall thickness of 20 mm and the measurement volume of 100 mm ´ 100 mm ´ 100 mm. The accuracy of 12 microns was achieved in the measurement of flat object three-dimensional geometry.