Design and Characterization of Optical Systems and Devices Using Non-Imaging Techniques: From Solar Concentrators to IR Bragg Mirrors

Abstract

Optical engineering is the creative application of classical optical principles to generate new technology. The most natural approach to engineer optical systems is to use image-forming techniques; however, it is possible to design and characterize optical technologies without the use of images. This concept is known as non-imaging optics. In the following work, I will present the design, prototyping, and characterization of solar and infrared (IR) technologies using non-sequential ray tracing techniques and non-imaging optical tools. There is a strong emphasis on tolerancing for fabrication and alignment purposes in all the designs. In the first project, large parabolic mirrors are used in a hybrid thermal/concentrated photovoltaics (CPV) collector to concentrate sunlight and store it as thermal energy. A comprehensive opto-mechanical tolerance analysis of the system is presented. I will also discuss the characterization of the optical throughput of its components and the preliminary PV and thermal data of a full-scale (8.0 × 5.0 m^2 ) demo. In the second project, concentrating refractive freeform optical devices are used to collect solar direct normal irradiance (DNI) and diffuse sunlight for multi-junction CPV cells. The design of several concentrators, from the optimization algorithm to prototyping methods, is discussed, including a 180× compact concentrator collecting 92% of the solar spectrum from 350 to 1400 nm. An algorithm to simulate the solar diffuse radiance for ray tracing simulations is also demonstrated. In the last project, I will examine the theoretical and experimental feasibility of fabricating IR Bragg mirrors using novel high refractive index sulfur-based polymers known as chalcogenide hybrid inorganic/organic polymers (CHIPs).