A New Approach to Optical Beam Shaping for Lighting Applications based on Nano-Optics
In this paper a new revolutionary approach to optical beam shaping for lighting applications is presented. The optical devices, developed by IQ Structures under the trade name Nanoptiqs are based on principles of diffraction, which are applied in a novel way to achieve improved performance of white light illumination systems. This unique solution is based on full control over the modulation of material and geometric properties of the optical elements at a nano-level. The surface (or volume) properties of the micro/nano structured optics are calculated with details as small as 10 nanometres, generally in three-dimensions. High complexity modelling of the light interaction with matter at nano-scale makes this task extremely computationally intensive. Moreover, manufacturing of three-dimensional optical nano-structures requires application of state-of-the-art mastering techniques with extreme spatial resolution such as electron-beam lithography, direct-writing based on multi-photon absorption and similar. These techniques together with in-house developed computational tools and high-precision mass-replication technologies stand behind Nanoptiqs unique properties, which promise an important role with these products not only in laboratory applications, but also in high capacity industrial production.
This contribution is focused on the explanation of physical principles of Nanoptiqs elements, description of selected approaches to computer modelling of optical nano-structures and optimization techniques developed particularly for design of advanced lighting systems. Commonly used approaches to design and analysis of diffractive elements are further extended for systems exploiting polychromatic light sources. The interaction of light with nano-structured materials is modelled using a hybrid approach based on a combination of ray-tracing methods with rigorous vectorial wave-optics techniques. Manufacturing of the designed elements using lithographic techniques is also discussed with focus on deep volume structures. Special attention is devoted to mass production of Nanoptiqs elements as this is a key factor for their future wide application in commercial practice. Besides improving the performance of current lighting solutions, the main benefits of Nanoptiqs are completely new design options and optical features following from full control of the light through nano-structured materials. Highly efficient mass production and reduced material and energy costs further emphasize attractiveness of presented approaches.
The paper also analyses possible future complex lighting systems consisting of a combination of transmission diffractive micro/nano elements with specially designed reflection systems. Nanoptiqs elements include hybrid systems using specially designed micro-reflectors. The technology of cost-effective (but simultaneously very precise) production of miniaturized systems of reflectors with complex shapes is a part of the proposed solution. Finally, the cooperation of IQ Structures with company Crytur is briefly mentioned, which focuses on the first application of Nanoptiqs directly on the surface of LED phosphor parts. Such a combination leads to a significant improvement in efficiency of LED light sources.