Foil based optical elements for beam shaping and color homogenization of phosphor converted white LED sources

Franz P. Wenzl; Wolfgang Nemitz; Ladislav Kuna; Christian Sommer; Paul Fulmek; Johann Nicolics; Peter Pachler; Hans Hoschopf; Franz Schrank; Gregor Langer; Paul Hartmann

doi:10.1117/12.2061944

25 September 2014 Foil based optical elements for beam shaping and color homogenization of phosphor converted white LED sources

Franz P. Wenzl, Wolfgang Nemitz, Ladislav Kuna, Christian Sommer, Paul Fulmek, Johann Nicolics, Peter Pachler, Hans Hoschopf, Franz Schrank, Gregor Langer, Paul Hartmann

Author Affiliations +

Proceedings Volume 9190, Thirteenth International Conference on Solid State Lighting; 91900A (2014) https://doi.org/10.1117/12.2061944
Event: SPIE Optical Engineering + Applications, 2014, San Diego, California, United States

Abstract

Typically, light emission from light-emitting diodes (LEDs) occurs under a broad range of angles. On the other hand, for a lot of applications a more directed light emission is desired. This can be realized with the use of additional optical elements, like lenses. Still, this may provide some complications in case of light sources consisting of a plurality of individual LEDs, e.g., a panel light, which is expected to illuminate a target area homogenously. Instead of a homogeneous illumination, the use of lenses is prone to give reason for an inhomogeneous light distribution in which the emission from the individual LEDs is easily distinguishable. Therefore, there is a strong request for alternative strategies of beam shaping of LED light in LED-luminaires targeting both on a directed as well as homogeneous illumination of an area. In this contribution we discuss an alternative approach in this regard: Firstly, a collimator is designed, which strongly directs the light emitted from a single LED light source. Subsequently, a foil with an optical structure, that can be fabricated in a cost-effective way by soft-lithography and which diffuses the collimated light again, is applied on the collimator. The optical structure and the respective amount of light diffusion are designed in a way that the desired radiation patterns both from a single as well as a plurality of LED sources can be realized. In addition, we show that the realization of a desired radiation profile is not the only advantage of such an approach. A key benefit of this concept is the possibility to reduce the angle dependent inhomogeneity

Citation Download Citation

Franz P. Wenzl, Wolfgang Nemitz, Ladislav Kuna, Christian Sommer, Paul Fulmek, Johann Nicolics, Peter Pachler, Hans Hoschopf, Franz Schrank, Gregor Langer, and Paul Hartmann "Foil based optical elements for beam shaping and color homogenization of phosphor converted white LED sources", Proc. SPIE 9190, Thirteenth International Conference on Solid State Lighting, 91900A (25 September 2014); https://doi.org/10.1117/12.2061944

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available