Modeling of Microlens Arrays with Different Lens Shapes Abstract

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Modeling of Microlens Arrays with Different Lens Shapes Abstract Microlens arrays are found useful in many applications, such as imaging, wavefront sensing, light homogenizing, and so on. Due to different fabrication techniques / processes, the microlenses may appear in different shapes. In this example, microlens array with two typical lens shapes – square and round – are modeled. Because of the different apertures shapes, the focal spots are also different due to diffraction. The change of the focal spots distribution with respect to the imposed aberration in the input field is demonstrated. 2 www.LightTrans.com Modeling Task 1.24mm 4.356mm 150µm input field - wavelength 633nm How to calculate field on focal - diameter 1.5mm - uniform amplitude plane behind different types of - phase distributions microlens arrays, and how 1) no aberration does the spot distribution 2) spherical aberration ? 3) coma aberration change with the input field 4) trefoil aberration aberration? x z or x z y 3 Results x square microlens array wavefront error [휆] z round microlens array [mm] [mm] y y x [mm] x [mm] no aberration x [mm] (color saturation at 1/3 maximum) or diffraction due to square aperture diffraction due to round aperture 4 Results x square microlens array wavefront error [휆] z round microlens array [mm] [mm] y y x [mm] x [mm] spherical aberration x [mm] Fully physical-optics simulation of system containing microlens array or takes less than 10 seconds. 5 Results x square microlens array wavefront error [휆] z round microlens array [mm] [mm] y y x [mm] x [mm] coma aberration x [mm] Focal spots distribution changes with respect to the or aberration of the input field. 6 Results x square microlens array wavefront error [휆] z round microlens array [mm] [mm] y y x [mm] x [mm] trefoil aberration x [mm] Focal spots distribution changes with respect to the or aberration of the input field. 7 Document Information title Modeling of Microlens Array with Different Lens Shapes version 1.0 VL version used for 7.3.1.5 simulations category Application Use Case 8 www.LightTrans.com.

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