Ultra-compact on-chip LED collimation optics by 3D femtosecond direct laser writing.

By using two-photon lithographic 3D printing, we demonstrate additive manufacturing of a dielectric concentrator directly on a LED chip. With a size of below 200 μm in diameter and length, light output is increased by a factor of 6.2 in collimation direction, while the emission half-angle is reduced by 50%. We measure excellent form fidelity and irradiance patterns close to simulation. Additionally, a more complex shape design is presented, which exhibits a nonconventional triangular illumination pattern. The introduced method features exceptional design freedoms which can be used to tailor high-quality miniature illumination optics for specific lighting tasks, for example, endoscopy.

[1]  Julio Chaves,et al.  Introduction to Nonimaging Optics , 2008 .

[2]  H. Giessen,et al.  Sub-micrometre accurate free-form optics by three-dimensional printing on single-mode fibres , 2016, Nature Communications.

[3]  M. Lazić,et al.  Rheology properties and acylglycerols and fatty acids composition of the wheat flour supplemented with Boletus edulis flour , 2015 .

[4]  K. Streubel,et al.  High-efficiency resonant-cavity LEDs emitting at 650 nm , 2001, IEEE Photonics Technology Letters.

[5]  R Schmogrow,et al.  Photonic wire bonding: a novel concept for chip-scale interconnects. , 2012, Optics express.

[6]  Harald Giessen,et al.  Two-photon direct laser writing of ultracompact multi-lens objectives , 2016, Nature Photonics.

[7]  Boris N. Chichkov,et al.  Parallel direct laser writing of micro-optical and photonic structures using spatial light modulator , 2015 .

[8]  R Di Leonardo,et al.  Focusing and imaging with increased numerical apertures through multimode fibers with micro-fabricated optics. , 2013, Optics letters.

[9]  Zach DeVito,et al.  Opt , 2017 .

[10]  Strong light-extraction enhancement in GaInN light-emitting diodes patterned with TiO2 micro-pillars with tapered sidewalls , 2012 .

[11]  G. Batavičiūtė,et al.  Characterization of photopolymers used in laser 3D micro/nanolithography by means of laser-induced damage threshold (LIDT) , 2014 .

[12]  R. Gadonas,et al.  Femtosecond laser polymerization of hybrid/integrated micro-optical elements and their characterization , 2010 .

[13]  Yan Li,et al.  High efficiency multilevel phase-type Fresnel zone plates produced by two-photon polymerization of SU-8 , 2010 .

[14]  David Hillerkuss,et al.  Photonic Wire Bonds for Terabit/s Chip-to-Chip Interconnects , 2011, 1111.0651.

[15]  E Fred Schubert,et al.  Effects of the refractive index of the encapsulant on the light-extraction efficiency of light-emitting diodes. , 2011, Optics express.

[16]  Joel R. Wendt,et al.  InGaN/GaN quantum-well heterostructure light-emitting diodes employing photonic crystal structures , 2004 .

[17]  M. Wegener,et al.  Direct laser writing of three-dimensional photonic-crystal templates for telecommunications , 2004, Nature materials.

[18]  Mangirdas Malinauskas,et al.  Monolithic generators of pseudo-nondiffracting optical vortex beams at the microscale , 2013 .