Integration of 3D printed lens with InGaN light-emitting diodes with enhanced light extraction efficiency

Yu Kee Ooi; Christopher Ugras; Cheng Liu; Matthew Hartensveld; Shaunak Gandhi; Denis Cormier; Jing Zhang

doi:10.1117/12.2252734

20 February 2017 Integration of 3D printed lens with InGaN light-emitting diodes with enhanced light extraction efficiency

Yu Kee Ooi, Christopher Ugras, Cheng Liu, Matthew Hartensveld, Shaunak Gandhi, Denis Cormier, Jing Zhang

Author Affiliations +

Proceedings Volume 10115, Advanced Fabrication Technologies for Micro/Nano Optics and Photonics X; 1011508 (2017) https://doi.org/10.1117/12.2252734
Event: SPIE OPTO, 2017, San Francisco, California, United States

Abstract

III-nitride based light-emitting diodes (LEDs) have great potential in various applications due to their higher efficiency and longer lifetime. However, conventional planar structure InGaN LED suffers from total internal reflection due to large refractive index contrast between GaN (n_GaN = 2.5) and air (n_air = 1), which results in low light extraction efficiency (η_extraction). Accordingly, various approaches have been proposed previously to enhance the η_extraction. Nevertheless, most of the proposed methods involve elaborated fabrication processes. Therefore, in this work, we proposed the integration of three-dimensional (3D) printing with LED fabrication as a straightforward and highlyreproducible method to improve the η_extraction. Specifically, 500-μm diameter dome-shaped lens of optically transparent acrylate-based photopolymer is 3D-printed on planar structure 500 × 500 μm2 blue-emitting LEDs. Light output power measurement shows that up to 9% enhancement at injection current 4 mA can be obtained from the LEDs with 3D printed lens on top as compared to LEDs without the lens. Angle-dependent electroluminescence measurement also exhibits significant light output enhancement between angles 0 and 30° due to the larger photon escape cone introduced by the higher refractive index of the 3D printed lens (n_lens = 1.5) than the air medium as well as the enhanced light scattering effect attributed to the curvature surface of the 3D printed lens. Our simulation results based on 3D finitedifference time-domain method also show that up to 1.61-times enhancement in η_extraction can be achieved by the use of 3D-printed lens of various dimensions as compared to conventional structure without the lens.

Conference Presentation

Citation Download Citation

Yu Kee Ooi, Christopher Ugras, Cheng Liu, Matthew Hartensveld, Shaunak Gandhi, Denis Cormier, and Jing Zhang "Integration of 3D printed lens with InGaN light-emitting diodes with enhanced light extraction efficiency", Proc. SPIE 10115, Advanced Fabrication Technologies for Micro/Nano Optics and Photonics X, 1011508 (20 February 2017); https://doi.org/10.1117/12.2252734

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