Lithographically defined optical nanostructures can be used to design various fundamental optical functions, including polarization, phase, refraction, and wavelength management. This paper describes the design, fabrication, and manufacturing of free-space discrete and integrated optical devices based on optical nanostructures. These devices are fabricated using a nanomanufacturing platform based on wafer-level nanoreplication with mold and nanopattern transfer by means of nanolithography. The nanoreplication process, based on imprinting a single-layer spin-coated ultraviolet (UV)-curable resist, achieved excellent nanopatterning fidelity and on-wafer uniformity with high throughput. It also achieved excellent wafer-level performance and yield. Nano-optical devices (NODs) (e.g., infrared polarizers and true zero-order quarter waveplates) and integrated NODs (e.g., monolithically integrated semi-isolators and visible circular polarizers) may be fabricated using the nanomanufacturing platform. The developed technology is suitable for the high-throughput and low-cost manufacturing needed to commercialize nanostructure-based optical devices and integrated optical devices. The success of the developed nano-engineering technology will lead to a redefinition of optical device manufacturing and integration and the functional and economic displacement of traditional bulk-optics devices. © 2005 Lucent Technologies Inc.