Applications of subaperture stitching interferometry for very large mirrors

Full aperture interferometric metrology has enabled fabrication and verification of large primary mirrors with nm precision. The measurement of mirrors that are several meters in diameter with flat or convex aspheric surfaces can be performed using interferometric measurements of overlapping subaperture regions, then stitching the date from these measurements together to provide a full map. This paper explores the application of this measurement technique for very large mirrors, and discusses issues for measuring large flat or convex mirrors.