Performance Enhancement and Applications Review of Nano Light Emitting Device (LED) (original) (raw)
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Nanomaterials, 2020
LENS (Light Emitting Nano-pixel Structure), a new nano-metric device, was designed, simulated, and modeled for feasibility analysis, with the challenge of combining high resolution and high brightness for display, essentially adapted for Augmented Reality (AR) and Virtual Reality. The device is made of two parts: The first one is a reflective nano-cone Light Emitting Device (LED) structure to reduce the Total Internal Reflection effects (TIR), and to enable improved light extraction efficiency. The second part is a Compound Parabolic Concentrator (CPC) above the nano-LED to narrow the outgoing light angular distribution so most of the light would be "accepted" by an imaging system. Such a way is drastically limiting any unnecessary light loss. Our simulations show that the total light intensity gain generated by each part of the pixel is at least 3800% when compared to a typical flat LED. It means that, for the same electrical power consumption, the battery life duration i...
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IntechOpen eBooks, 2022
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IEE Proceedings - Optoelectronics, 2001
An analytic model of thc optical behaviour of laterally light emitting thin film structures is dcveloped. It is employed to calculate the outcoupled light of a pixcl used in light emitting dot matrix displays such as laterally cmitting thin film electrolumincsccnt displays (LETFEL) with micromirrors. Consequently, one can identify the optiinum pixcl geomctry. Here, the optical behaviour of thc circular, square and hexagonal pixel geometry is modelled. The presented closed form solutions are based on a ray optics approximation whereby the absorption of the light within the light generating medium (phosphor material) and the transrnission bchaviour of the phosphorair interfacc is taken into account, as well as the inicroinirror width. Thcsc solutions, however, neglect back reflected light. The effect of this neglect is investigatcd for square pixels by taking into account the first rcflection. The model is applied to a typical LETFEL display with ZnS material doped with Mn. An optimal pixel diameter of 35 pm is estimated for that particular type of display.
Rigorous simulations of emitting and non-emitting nano-optical structures
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