C35 Precision Shape Measurement of Large Aspheric Optics Based on Error Compensation
Details
A precision shape measurement system on SPDT machine tool is built based on error compensation for obtaining the better machining accuracy of large aspheric optics. A series of errors of machining and machine tool were compensated with a specially made straightness gauge. Measurement reference start point is decided accurately by a new approach algorithm at the intersection of two aspheric surfaces. As the result, an electroless nickel coated aspheric optic was machined based on this system, the geometric shape error was decreased to less than ± 120 nm from a few microns in 200 mm mirror range.
