Sub-aperture stitching interferometry using stereovision positioning technique. 
A stereovision-assisted sub-aperture stitching (SAS) approach is proposed to solve the positioning problem of tested optics.  The principle of stitching is analyzed and the overlapping calculation problem is simplified.  Then, a binocular stereovision system is integrated into a test configuration.  By measuring the coordinates of marks attached to the fixture in different positions, the stereovision system obtains the position and pose data of the optics to provide the initial values for optimization algorithm.  The key benefit of stereovision is that the SAS test is easily performed without a precision positioning system.  A simulation and practical examples are given to demonstrate the performance of this method.  The stitching result shows good agreement with the full-aperture result.