Focal properties of geodesic waveguide lenses

Abstract

The focal properties of uncorrected geodesic lenses in ion‐exchanged glass waveguides are reported. A 13.8‐mm‐focal‐length lens resolved by beams with an angular separation of 27.6 mrad, while a 28‐mm‐focal‐length lens resolved beams with an angular separation of only 3.3 mrad. Intensity profiles of the focal region of the former lens revealed a 40‐μ spot size when the input aperture was 5 mm, and a spot size of 7.7 μ when the aperture was reduced to 1 mm. This value is close to the diffraction‐limited spot size of 5.7 μ.