Share Email Print

Proceedings Paper

Extracting and shaping the light of OLED devices
Author(s): Daniel Riedel; Julian Dlugosch; Thomas Wehlus; Christoph Brabec
Format Member Price Non-Member Price
PDF $14.40 $18.00

Paper Abstract

Before the market entry of organic light emitting diodes (OLEDs) into the field of general illumination can occur, limitations in lifetime, luminous efficacy and cost must be overcome. Additional requirements for OLEDs used for general illumination may be imposed by workplace glare reduction requirements, which demand limited luminance for high viewing angles. These requirements contrast with the typical lambertian emission characteristics of OLEDs, which result in the same luminance levels for all emission angles. As a consequence, without additional measures glare reduction could limit the maximum possible luminance of lambertian OLEDs to relatively low levels. However, high luminance levels are still desirable in order to obtain high light output. We are presenting solutions to overcome this dilemma.

Therefore this work is focused on light-shaping structures for OLEDs with an internal light extraction layer. Simulations of beam-shaping structures and shapes are presented, followed by experimental measurements to verify the simulations of the most promising structures. An investigation of the loss channels has been carried out and the overall optical system efficiency was evaluated for all structures. The most promising light shaping structures achieve system efficiencies up to 80%.

Finally, a general illumination application scenario has been simulated. The number of OLEDs needed to illuminate an office room has been deduced from this scenario. By using light-shaping structures for OLEDs, the number of OLEDs needed to reach the mandatory illuminance level for a workplace environment can be reduced to one third compared to lambertian OLEDs.

Paper Details

Date Published: 22 September 2015
PDF: 9 pages
Proc. SPIE 9566, Organic Light Emitting Materials and Devices XIX, 95661H (22 September 2015); doi: 10.1117/12.2186957
Show Author Affiliations
Daniel Riedel, OSRAM OLED GmbH (Germany)
Friedrich-Alexander-Univ. Erlangen-Nürnberg (Germany)
Julian Dlugosch, OSRAM OLED GmbH (Germany)
Thomas Wehlus, OSRAM OLED GmbH (Germany)
Christoph Brabec, Friedrich-Alexander-Univ. Erlangen-Nürnberg (Germany)

Published in SPIE Proceedings Vol. 9566:
Organic Light Emitting Materials and Devices XIX
Franky So; Chihaya Adachi; Jang-Joo Kim, Editor(s)

© SPIE. Terms of Use
Back to Top