The Wavefront Power Spectral Density Measurement of Aspheric Lens with Long Focal-Length Using a Computer-Generated Hologram

To ensure the performance of optical system, machining accuracy lens with long focal lengths is required to image quality. A new method for transmission wavefront power spectral density (PSD) in mid-frequency domain measurement using binary phase computer-generated hologram (CGH) presented. This technique widely applicable and particularly useful measuring large-size lenses lengths. comparison experiment CGH results from a Fizeau sphere interferometry carried out verify convenience measurement. Furthermore, uncertainty due fabrication process analysed. Analysis test showed overall less than 1 nm RMS over 30 m length Φ410 mm clear aperture. can provide reference spheres high precision, meantime greatly shorten air space, thus reducing effect vibration turbulence, therefore great importance PSD The realization efficiency nondestructive testing focal-lens ultra-precision certainty level machining, hence improving comprehensive system.