Precise optical model of multi-chip white LEDs

Precise optical model of multi-chip white LEDs.

A single-chip white light LED is commonly modeled by considering the phosphor coating as a homogeneous Lambertian light source. However, this approach leads to an incorrect optical simulation of phosphor-coated multi-chip LEDs due to the presence of a previously unreported spatial distribution of emission spots across the phosphor layer. We introduce "weighting" factors based on position-depend...

Nanophosphors for White Light Leds

Precise slit-width control of niobium apertures for superconducting LEDs.

We introduce a novel three-step procedure for precise niobium (Nb)-etching on the nanometer-scale, including the design of high contrast resist patterning and sacrifice layer formation under high radio frequency (RF) power. We present the results of precise slit fabrication using this technique and discuss its application for the production of superconducting devices, such as superconductor-sem...

Cup-shaped copper heat spreader in multi-chip high-power LEDs application.

In this study, cup-shaped copper sheets were developed to improve heat dispassion for high-power light emitting diodes (LEDs) array module (3 × 3, 4 × 4, and 5 × 5) using an electroplating technique. The cup-shaped copper sheets were directly contacted with sapphire to enhance the heat dissipation of the chip itself. The lateral emitting light extraction and heat dissipation of high-power LEDs ...

Application of Multi Flux Model to Predict Optical Performance of Titanium Dioxide Nanopigments

   The area of nano-pigments is a limitless field with exceptional potential applications in industry, and their application is becoming the focus of many research groups worldwide in recent years due to their outstanding and tunable properties. Titanium dioxide (TiO2) nanoparticles, on the other hand, are among the most widely used pigment particles, and the interest for utiliza...