Precision optical 3D sensors with active optical elements

Optical 3D sensors measure the geometric shape of objects. The most accurate optical 3D sensors, suitable for measuring objects with a rough surface (which is most commonly used technical surfaces) are white light interferometry and the variable focus technique. However, even these methods, although successful and widely used, have certain limitations. The most important of these are the small image field and the need for deep scanning (the measured object moves relative to the measuring device). The aim of this project is to develop an optical 3D sensor based on interferometry in white light, which measures without deep scanning. The output of a fiber interferometer is used as the light source for the measuring interferometer. An optical modulator inserted into one arm of the fiber interferometer changes the difference in optical paths between the arms of the interferometer so that the spectrum at the output of the interferometer is periodic. Changing the spectral period replaces the deep scan. The variable focal length lens ensures the correct position of the focus plane.