The invention discloses a
system and a method for accurately calibrating an
optical path of a
point diffraction interferometer based on image information. The
system comprises spectroscopic prisms, abeam expanding collimation
system, a
diffraction orifice plate, a wave-front sensor, lenses, an
optical power meter, three-
dimensional precision electronically controlled translation stage and driverthereof, a CCD1 (charge-coupled device), and a computer. The method comprises the following steps of: analyzing and obtaining a
mathematical relationship between an alignment error and a
diffraction wave-front deviation by using the Rayleigh-Sommerfeld
diffraction theory; designing an accurate
optical path calibration system according to requirements to obtain a spot-hole alignment image and lightintensity before and after the diffraction
orifice plate; then analyzing and measuring alignment deviation information through an
image processing algorithm to establish a
mathematical model betweenthe measurement quantity and the control quantity; and finally, achieving accurate calibration according to a system implementation principle. According to the system and the method for accurately calibrating the
optical path of the
point diffraction interferometer based on the image information, the precise alignment of the diffraction holes and the spot in the visual environment is realized, andthe influence of the alignment deviation on the detection precision of the
point diffraction interferometer to some extent is eliminated. The system and the method have characteristics of high precision and high efficiency, and reduce the damage of the
laser to the vision of operators during experimental operation.