Top-level requirement Implied requi

Top-level requirement Implied requirementsMinimum requirements1.Guide figuring to within capture range of principal optical test.2.Reduce geometry errors (R, off-axis distance, clocking) to levels that can be corrected by polishing (~10 µm p-v surface). 1.Net accuracy of 2 µm rms for first 10-15 Zernike polynomials.2.Measure distance from tracker to segment to 0.6 mm.•equiv to 1 µm rms defocus3.Measure physical references at edge of segment to 1 mm.•limits focus and astigmatism to ~1 µm rmsGoals1.Verify that focus and astigmatism are small enough to be corrected within ~half of 30 N rms force budget for active correction.2.Determine radius of curvature to 0.5 mm.3.Determine off-axis distance to 2 mm and clocking angle to 50 arcseconds. 1.Measure astigmatism to 1 µm rms surface•correctable with 12 N rms force2.Measure defocus to 0.5 µm rms.•equiv to 0.3 mm radius error•correctable with 17 N rms force3.Measure distance from tracker to segment to 0.3 mm.4.Measure physical references at edge of segment to0.5 mm.•equiv to 25 arcseconds clockingAmbitious goals1.Verify that focus, astigmatism and coma are small enough to be corrected within 30 N rms force budget.2.Determine radius of curvature to 0.3 mm.3.Determine off-axis distance to 1 mm. 1.Measure astigmatism to 0.5 µm rms surface•corresponds to 1 mm change in off-axis distance•correctable with 6 N rms force2.Measure coma to 0.14 µm rms surface•correctable with 20 N rms force3.Measure defocus to 0.3 µm rms.•equiv to 0.2 mm radius error•corresponds to 0.4 mm change in off-axis distance•correctable with 10 N rms force4.Measure distance from tracker to segment to 0.2 mm.