We present a method to obtain the average lenslet shape of microlens arrays and especially their aberrations from the far-field intensity distribution of the whole array. The method is based on the phase-retrieval algorithm introduced by Gerchberg and Saxton [Optik (Stuttgart) <b>35,</b> 237 (1972)]. We show how to overcome the crucial point of this algorithm, that is finding suitable start parameters to end up with correct results. The procedure is successfully applied to a cylindrical microlens array produced by reflow technique and the result is compared with surface profilometric measurements. The technique is applicable for lenslets having small numerical apertures and fill factors near unity.
© 2002 Optical Society of America
(070.0070) Fourier optics and signal processing : Fourier optics and signal processing
(100.5070) Image processing : Phase retrieval
(120.0120) Instrumentation, measurement, and metrology : Instrumentation, measurement, and metrology
(120.4630) Instrumentation, measurement, and metrology : Optical inspection
Alexander Büttner and Uwe D. Zeitner, "Calculation of the Average Lenslet Shape and Aberrations of Microlens Arrays from Their Far-Field Intensity Distribution," Appl. Opt. 41, 6841-6848 (2002)