The progress in solar energy has been driven by the fields of optics, solid-state physics, thermal science, materials and chemistry. They play a key role in the development of present and future solar energy technologies. Optical elements are used for collecting, guiding, concentrating, coupling, trapping, transforming and absorbing the light in solar energy systems. The Optics for Solar Energy (SOLAR) Conference focuses on optical science and its applications to solar energy conversion, mainly in the areas of solar thermal, concentrating photovoltaics and new-type solar cell such as perovskite solar cell, two dimensional semiconductor devices, organic solar cell, nano-structured semiconductor solar cell and so on, but not limited on the above mentioned novel type SOLAR technology. All these areas are experiencing rapid progress, which strongly relies on the advances in efficiency, cost, and reliability of their optical elements. Fundamental and applied concepts are addressed at the conference and they include the design, modeling, optimization, integration, experimental evaluation, manufacturability, reliability, and techno-economics of solar energy systems, as well as the use of novel materials in all aspects of such systems. This conference has attracted professionals and scientists from many different scientific and industrial areas, creating a multidisciplinary arena to discuss technical challenges beyond the state-of-the-art. Optical scientists, physicists, engineers and industry managers are brought together to discuss the most novel developments in the field with the aim of improving the competitiveness of solar energy.