A blue phosphor Ca 2 PO 4 Cl : Eu 2+ was synthesized by solid state reaction and evaluated as a candidate for white LEDs. The luminescent intensity of Ca 2 PO 4 Cl : Eu 2+ was found to be 128% under excitation at 380 nm, 149% under 400 nm, and 247% under 420 nm, as high as that of BaMgAl 10 O 17 : Eu 2+ . Furthermore, Ca 2 PO 4 Cl : Eu 2+ reveals high quantum efficiency and excellent thermal stability. By utilizing a mixture of blue-emitting Ca 2 PO 4 Cl : Eu 2+ , green-emitting (Ba,Sr) 2 SiO 4 : Eu 2+ and redemitting CaAlSiN 3 : Eu 2+ as light converters, an intense white GaN-based n-UV-LED (400 nm) was fabricated to exhibit an excellent color-rendering index R a of 93.4 at a correlated color temperature of 4590 K. Based on the results, we are currently evaluating the potential application of Ca 2 PO 4 Cl : Eu 2+ as a blue-emitting near-UV convertible phosphor.

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CSP (Chip scale package) LEDs have drawn intensive attention lately since it provides multiple times power density than traditional packages. Higher power density brings possibilities of better light control and more industrial applications in UV LED applications. Therefore, a chip scale LED package of 2.0 x 1.6 mm, named 2016, has been designed and fabricated for UV applications. The LED package is fabricated by dispensing highly thixotropic encapsulant to form a encapsulation layer. It's cost-effective and brief in production flow. In this paper, an optical model of 2016 LED package with a dispensed encapsulation layer is constructed for analysis. Variables including encapsulant height are studied by optical simulations. In order to validate the 2016package with production deviations, ray files of the resulting packages are then applied to a three-row silica collimator for high irradiance UV LED module as a test vehicle. After intentional designing for the manufacture window in production, total flux decreases by 5% and peak irradiance decreases by 3% even in the corner case with SMT deviations in the collimator. It then leads to a conclusion that 2016 UV LED with dispensed encapsulant could be applied to UV curing applications well.

Dome lens formation method through dispensing highly thixotropic encapsulant [1] has been introduced into LED industry for several years. It's cost-effective and concise in production flow, but not qualified yet when accurate optical properties are needed. Most of directional fixtures therefore require LED packages with precisely molded dome lenses, which need complex and expensive processes. In this paper, an optical model of LED package with dispensed dome lens is built for analysis. Variables including LED chip position, chip height and lens diameter are investigated through optical simulations. In order to validate the package with production deviations, ray files of the resulting packages are then applied to a linear collimator for high irradiance UV LED module as a test vehicle. The result shows that after intentionally designing for the process window in production, the package's light pattern is stable and its mean direction bias is below 2 degrees under deviations. Peak irradiance drops by 6.3% and total flux drops by 1% even in the corner case with surface mount technology (SMT) deviations in the linear collimator. It then leads to a conclusion that when dispensed dome lens has been well designed for process window, dispensed dome lens could be applied to lighting applications as well.