Design of Slim LED Coupler for Collimated Light Source

  • Chun-Hao Sun
  • Tun-Chien Teng


This study proposed a slim coupler to collimate the light emitted from an LED, which can be used as a collimated light source. The coupler is substantially a 2-D compound parabolic collector (CPC); its bottom surface has longitudinally extending V-groove microstructures thereon. The parabolic side walls reflect the propagating light to converge only in the transverse direction, but the V-groove microstructures reflect the light and make its propagating direction gradually rotates around a central axis of the CPC. Therefore, the angular distribution of the light finally converges after several times of reflection on both side walls and V-groove microstructures. Moreover, the illuminance distribution on the outlet of the V-groove CPC becomes more uniform than a CPC without V-groove microstructures. The effects of V-groove microstructures on both angular and illuminance distributions of the light emerging from the outlet of the CPC is analyzed, and the feasibility of providing a uniform collimated light source is verified by conducting simulation.


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How to Cite
Sun, C.-H., & Teng, T.-C. (2016). Design of Slim LED Coupler for Collimated Light Source. Proceedings of Engineering and Technology Innovation, 3, 7-9. Retrieved from