Hybrid Down-Converting Structures for Solid State Lighting

Achieving higher luminous efficacy in phosphor converted light emitting diodes (pcLED) requires breakthroughs in down-converting materials that provide high conversion efficiency, tunable narrow bandwidth emission, and temperature/chemical stability. To achieve these goals, PhosphorTech (PTC) and its partners propose the development of high performance hybrid inorganic down-converting (HID) material systems for high brightness LED (HBLED) applications. While conventional bulk phosphors are currently the dominant down-converters used in high power solid-state lighting (SSL) applications, their performance is limited by intrinsic properties such as high scattering cross-sections and large emission bandwidth. On the other hand, conventional luminescent nanocrystals (e.g, quantum dots or QDs) have high self- absorption and poor thermal and chemical stability for HB LEDs. By designing an all- inorganic hybrid system, PTC believes that the new HID materials will outperform both bulk phosphors and conventional QDs. Ultimately, these materials will enable a new generation of solid state lighting devices with high luminous efficacies, high color and thermal stability, and with spectral efficiency near the theoretical maximum luminous efficacy of radiation (LER), as a result of their color tunability and narrow bandwidths (FWHM < 30nm).