A novel LED light source based on large, flexible and transparent substrates has been developed with help from an easy-to-customize LED foil. The light source, developed at the VTT Technical Research Centre of Finland, can be mass produced and used in applications such as vehicles, greenhouses, shopping centers and architectural lighting. VTT is working with Finnish companies Flexbright and Lighting Design Collective on a three-year European project called Delphi4LED. Their main objective is to develop a standardized method to create multi-domain (thermal-optical-electrical) LED-based design and simulation tools for the solid-state lighting industry. The Delphi4LED project has developed a tool that enables mass production of high quality large-area LEDs that cost less. Courtesy of Flexbright. Heat management is a key factor dictating the performance and reliability of LED lighting solutions. The operation of LED components is also affected by their electrical and optical characteristics. Combining all of these properties is difficult using the existing design tools. Researchers in the Delphi4LED project have developed new simulation models to consider these factors in simplified form, ultimately saving computing capacity and enabling a more comprehensive design than is currently possible. Researchers hope to make the design process more efficient and reduce the number of design errors. This will allow faster production and faster introduction of the products on the market, with higher quality and a lower cost. A Finnish consortium coordinated by VTT Technical Research Centre of Finland is applying the results of the Delphi4LED project to the development of LED luminaires based on transparent large-area foil. These kinds of novel structures enable the implementation of a thin, flexible light source for lighting and display applications. The project is being coordinated by Philips Lighting from the Netherlands. Other partners in the consortium are Technische Universiteit Eindhoven from the Netherlands; Havells Sylvania Lighting Belgium from Belgium; Magillem Design Services SAS, Ingélux, PISEO, Philips France and Ecce'Lectro from France; Budapest University of Technology & Economics and Mentor Graphics Hungary from Hungary; Mentor Graphics UK from the United Kingdom; and Pi Lighting SARL from Switzerland.