Led Luminaries

Cree has introduced an ‘S Line’ version of its XP-G3 led line – the remainder is now called ‘Standard’. “Through innovations in component architecture, the new XLamp XP-G3 S Line LED can withstand double the number of switching cycles when compared to competing leds in its class,” said Cree in the launch paperwork – leaving me to wonder if the ...

While pondering the heat shedding capability of a 100mm diameter sheet of 3mm thick aluminium with an led on a star board bolted to it, I came across the rule of thumb formula: Rha = 50/√(area in cm2) I believe this is for ‘sufficiently thick’ plates Does anyone know where this comes from? And if it suits horizontal flat plates ...

According to the University of Toledo, it has found a mechanism for a direct link between blue light exposure and age-related macular degeneration. A quick look at the scientific report revealed that when the researchers tried light at 445, 488, 515 and 594nm,  only light at 445nm did any damage. The university is mentions sunlight and screens – phone, tablet ...

A combination of IR (850nm), red (660nm) and violet (405nm) leds has proved effective against ulcers on fingers caused by the auto-immune disease systemic sclerosis, according to University of Manchester and Salford Royal NHS Foundation Trust which 14 ulcers amongst eight patients were exposed to 10J/cm2 for 15 minutes twice weekly for three weeks, with follow-up at weeks four and eight. ...

Gaggione has introduced a 67mm dia one-piece zoom collimator for 6mm diameter emitter CoBs – where is it said to zoom across ±5 to ±11° to 50% (10-22° FWHM) and ±9° to ±22.5° to 10% (18-45° FWTM). As this is zoomed simply by moving the one-piece collimator back and forth in front of the CoB, I was keen to see some beam ...

Cree has introduced a ‘High Efficacy’ (HE) version of its venerable XP-G2 led, making a device with “higher output and greater efficiency” compared with the original XP-G2. Cree has added some detail below The difference is the use of the “newest Dmax high-power chip technology”, said the firm. Branding over. The numbers are, said the firm: 25% greater output via a ...

A four year German industry and academia project has payed off, producing a new way to surface-mount very small led die and a technology demonstrator – a high intensity full-colour video wall module with emitters on a 1mm pitch. Running between December 2014 and February 2018, InteGreat was the project, with participants investigated existing manufacturing approaches and know-how along the entire ...

Samsung is offering red leds optimised for horticulture lighting, and some whites. LH351B Red is a high-power package providing 660nm red with a photosynthetic photon flux (PPF) of 2.15μmole/s at 350mA. “The 660nm wavelength helps to accelerate the growing of plants including their photosynthesis, as well as enrich the blooming of flowers,” said the firm. For heat extraction, thermal resistance ...

Flemish horticulturalist TomatoMasters is to install Plessey-made grow lights in a 54,560m² (5.4Ha) greenhouse development. Hyperion 1750 luminaires are being installed, rated at 1,750μmole/s, equivalent to a 1kW SON-T lamp. “All Hyperion grow lights come in a range of standard and tailor made spectrums, with a host of features and benefits designed to give a higher commercial return to growers,” said ...

Cree’s CMT metal-based chip-on-board (CoB) leds cover three light emitting surface (LES) diameters (9.8, 14.5 and 22mm) with 10 devices, which have options across 2,700-6,500K colour temperature and 70, 80 and 90 CRI, as well as premium colour options that include high fidelity (98 CRI) and speciality colour points. “With more than 6,000 hours of LM-80 data available, the expanded ...