Design the algorithm compensation of vignetting error at optical-electronic autoreflection system by modelling vignetted image

Nowadays one of metrology problems is the measurement of angular values, in particular, angular deformations in the critical points of oversized objects. For the solution of this problem, effectively use optoelectronic autoreflection systems. The autoreflection systems allows measuring a mirror turning angle as sensitive element in a point of angular deformation with a potential accuracy up to 0.05". Actually the error can exceed considerably the specified value because of existence of systematic error, one of which main components is the error flowing to vignetting of a working beam. The component of systematic error due to vignetting of the beam can be eliminated in case of existence of the analytical description of changes in irradiance distribution of the analyzed image. Because of the complexity of the analytical description of the vignetting processes proposes the use of computer models. Based on the received dependence for compensation of systematic error due to vignetting is equal D=30 arcsecs. As this systematic measurement error unacceptably large, there is a need to compensate for this error. For the design of the algorithm compensate for systematic error were considered three cases of displacement vignetting field on a matrix analyzer due to the rotation of control element. Using the compensation algorithm, the error due to the vignetting amounts to a negligible value 0.4 arcsecs. The designed algorithm compensation systematic error due to vignetting allows to increase the working distance at the autoreflection measurements.