Ozan Cakmakci

Optical design of a color-corrected 2.75 g visual loupe

Abstract. The key contribution is the optical design of a 2.75 g 2.5× magnification visual loupe developed within the Defense Advanced Research Projects Agency Manufacturable Gradient Index (M-GRIN) phase 2 program. We present a visual loupe (i.e., a Galilean telescope) that is constructed by a positive optical power objective lens that makes use of a spherical gradient index profile and a negative optical power eye lens that collimates the light for visual use. The optical materials and the preform thickness in the design are judiciously designed to be manufacturable within the spherical gradient index design rules available today. A comparison of the M-GRIN design to an all-plastic homogeneous baseline design shows that the M-GRIN design reduces the weight from 4.15 to 2.75 g while maintaining equivalent optical performance of the baseline.