Monthly Notices of the Royal Astronomical Society · 1977 · 107 citations · 0 references
Natural SciencesAstronomyPhysicsOptical AstronomyOpticsRadio AstronomyDiffractionFourier OpticsObservatory InstrumentationPhysical OpticsRadio TelescopesTelescope OpticsContour PlotsDiffraction Pattern AnalysisDish Surface AccuracyFourier TransformReflecting TelescopesReflector Surface AccuracyTelescopesZenith Telescope Measurements
The well-known Fourier Transform relationship between the complex illumination function and the diffraction pattern of an aperture has been applied to measurements of the reception patterns of dishes of the 5-km telescope; the results have provided contour maps showing the distribution of reflector surface errors with an accuracy of ~ 0.1 mm. By repeating the measurements at different zenith angles the structural deflections due to gravity were investigated.