Designing a Secondary Optical Freeform Lens for Signal Lighting
Faculty of Electrical Engineering and Computer Science, University of Applied Sciences Bremen; 2 Institute for microsensors, -actuators and -systems, University of Bremen
Abstract
The advantages of light-emitting diodes (LEDs) make them considered in many applications. Luminous intensity distribution of LEDs must be redistributed to meet the requirements of each specific application. Contrary to ordinary illumination applications, for signal lights the intensity distribution is specified to meet requirements regarding the brightness perception of users, not the illumination of an object. Freeform optical systems playing an important role in the field of illumination engineering for redistributing the Luminous intensity of LEDs. In this talk we present a part of results of eboLED project (Funded by the BMBF), using a new method of designing a secondary optical freeform lens dealing with the adaption of physical output properties to the requirements of signal lighting luminous intensity distribution. As an application, a freeform lens is designed for achieving a uniform luminous intensity distribution. After designing the freeform lens, the optical performance of the freeform lens is investigated by using a numerical simulation of optical ray tracing. In addition, tolerance analysis are presented.