The Experts below are selected from a list of 12645 Experts worldwide ranked by ideXlab platform
Hoi Wai Choi - One of the best experts on this subject based on the ideXlab platform.
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68.1: Angular Uniform White Light‐Emitting Diodes with an Internal Reflector Cup
SID Symposium Digest of Technical Papers, 2010Co-Authors: Ling Zhu, Xiang Hua Wang, Pui Tao Lai, Hoi Wai ChoiAbstract:We report on a white light-emitting diode (LED) with a truncated- conical (TC) geometry produced by laser micromachining. A blue LED was shaped into a circular disc with 50o-inclined sidewall using a modified laser micromachining setup. A layer of Al was coated onto the inclined sidewall and the bottom surface to form an integrated reflector. Due to the highly reflective mirror, laterally propagating photons were redirected into the Upward Direction, contributing to a 21.7 % increase of light intensity in the normal Direction. with quantum dots applied to the surface, white light emission from this TC-LED structure demonstrated a 37% enhancement in color uniformity, compared with a conventional device.
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Angularly Uniform White Light-Emitting Diodes Using an Integrated Reflector Cup
IEEE Photonics Technology Letters, 2010Co-Authors: Lixing Zhu, Xiang Hua Wang, Pui Tao Lai, Hoi Wai ChoiAbstract:We report on white light-emitting diodes (LEDs) with a truncated-conical (TC) geometry produced by laser micromachining. A blue LED was shaped into a circular disc with 50°-inclined sidewall using a modified laser micromachining setup. A layer of Al was coated onto the inclined sidewall and the bottom surface to form an integrated reflector. Due to the highly reflective mirror, laterally propagating photons are redirected into the Upward Direction, contributing to an increase of 21.7% of light intensity in the normal Direction. With quantum dots applied to the surface, white light emission from this TC-LED structure demonstrated a 37% enhancement in color uniformity, compared with a conventional device.
Lixing Zhu - One of the best experts on this subject based on the ideXlab platform.
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Angularly Uniform White Light-Emitting Diodes Using an Integrated Reflector Cup
IEEE Photonics Technology Letters, 2010Co-Authors: Lixing Zhu, Xiang Hua Wang, Pui Tao Lai, Hoi Wai ChoiAbstract:We report on white light-emitting diodes (LEDs) with a truncated-conical (TC) geometry produced by laser micromachining. A blue LED was shaped into a circular disc with 50°-inclined sidewall using a modified laser micromachining setup. A layer of Al was coated onto the inclined sidewall and the bottom surface to form an integrated reflector. Due to the highly reflective mirror, laterally propagating photons are redirected into the Upward Direction, contributing to an increase of 21.7% of light intensity in the normal Direction. With quantum dots applied to the surface, white light emission from this TC-LED structure demonstrated a 37% enhancement in color uniformity, compared with a conventional device.
Pui Tao Lai - One of the best experts on this subject based on the ideXlab platform.
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68.1: Angular Uniform White Light‐Emitting Diodes with an Internal Reflector Cup
SID Symposium Digest of Technical Papers, 2010Co-Authors: Ling Zhu, Xiang Hua Wang, Pui Tao Lai, Hoi Wai ChoiAbstract:We report on a white light-emitting diode (LED) with a truncated- conical (TC) geometry produced by laser micromachining. A blue LED was shaped into a circular disc with 50o-inclined sidewall using a modified laser micromachining setup. A layer of Al was coated onto the inclined sidewall and the bottom surface to form an integrated reflector. Due to the highly reflective mirror, laterally propagating photons were redirected into the Upward Direction, contributing to a 21.7 % increase of light intensity in the normal Direction. with quantum dots applied to the surface, white light emission from this TC-LED structure demonstrated a 37% enhancement in color uniformity, compared with a conventional device.
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Angularly Uniform White Light-Emitting Diodes Using an Integrated Reflector Cup
IEEE Photonics Technology Letters, 2010Co-Authors: Lixing Zhu, Xiang Hua Wang, Pui Tao Lai, Hoi Wai ChoiAbstract:We report on white light-emitting diodes (LEDs) with a truncated-conical (TC) geometry produced by laser micromachining. A blue LED was shaped into a circular disc with 50°-inclined sidewall using a modified laser micromachining setup. A layer of Al was coated onto the inclined sidewall and the bottom surface to form an integrated reflector. Due to the highly reflective mirror, laterally propagating photons are redirected into the Upward Direction, contributing to an increase of 21.7% of light intensity in the normal Direction. With quantum dots applied to the surface, white light emission from this TC-LED structure demonstrated a 37% enhancement in color uniformity, compared with a conventional device.
Xiang Hua Wang - One of the best experts on this subject based on the ideXlab platform.
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68.1: Angular Uniform White Light‐Emitting Diodes with an Internal Reflector Cup
SID Symposium Digest of Technical Papers, 2010Co-Authors: Ling Zhu, Xiang Hua Wang, Pui Tao Lai, Hoi Wai ChoiAbstract:We report on a white light-emitting diode (LED) with a truncated- conical (TC) geometry produced by laser micromachining. A blue LED was shaped into a circular disc with 50o-inclined sidewall using a modified laser micromachining setup. A layer of Al was coated onto the inclined sidewall and the bottom surface to form an integrated reflector. Due to the highly reflective mirror, laterally propagating photons were redirected into the Upward Direction, contributing to a 21.7 % increase of light intensity in the normal Direction. with quantum dots applied to the surface, white light emission from this TC-LED structure demonstrated a 37% enhancement in color uniformity, compared with a conventional device.
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Angularly Uniform White Light-Emitting Diodes Using an Integrated Reflector Cup
IEEE Photonics Technology Letters, 2010Co-Authors: Lixing Zhu, Xiang Hua Wang, Pui Tao Lai, Hoi Wai ChoiAbstract:We report on white light-emitting diodes (LEDs) with a truncated-conical (TC) geometry produced by laser micromachining. A blue LED was shaped into a circular disc with 50°-inclined sidewall using a modified laser micromachining setup. A layer of Al was coated onto the inclined sidewall and the bottom surface to form an integrated reflector. Due to the highly reflective mirror, laterally propagating photons are redirected into the Upward Direction, contributing to an increase of 21.7% of light intensity in the normal Direction. With quantum dots applied to the surface, white light emission from this TC-LED structure demonstrated a 37% enhancement in color uniformity, compared with a conventional device.
Stephen K. Wismath - One of the best experts on this subject based on the ideXlab platform.
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Volume requirements of 3D Upward drawings
Discrete Mathematics, 2009Co-Authors: Emilio Di Giacomo, Giuseppe Liotta, Henk Meijer, Stephen K. WismathAbstract:This paper studies the problem of drawing directed acyclic graphs in three dimensions in the straight-line grid model so that all directed edges are oriented in a common (Upward) Direction. We show that there exists a family of outerplanar directed acyclic graphs whose volume requirement is super-linear. We also prove that for the case of directed trees a linear-volume upper bound is achievable.
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Graph Drawing - Volume requirements of 3d Upward drawings
Graph Drawing, 2006Co-Authors: Emilio Di Giacomo, Giuseppe Liotta, Henk Meijer, Stephen K. WismathAbstract:This paper studies the problem of drawing directed acyclic graphs in three dimensions in the straight-line grid model, and so that all directed edges are oriented in a common (Upward) Direction. We show that there exists a family of outerplanar directed acyclic graphs whose volume requirement is super-linear. We also prove that for the special case of rooted trees a linear volume upper bound is achievable.
