Following research at Sheffield-based LED packaging firm Litecool, narrow beam angles from LED packages without secondary optics or reflectors look closer. The proof-of-concept device produced a beam with 50% of light in 36 degrees, and over 90% efficiency. “Most package manufacturers design their LED packages for maximum light extraction. This means as little manipulation of […]
Narrow beam angles from small LED packages Read More »
LED and OLED lighting, which is generally called solid-state lighting (SSL), is becoming more common as the next generation lighting. Evaluations of total luminous flux (a performance index for lighting) and color are important for SSL, and to evaluate those values, it is indispensable to measure the light intensity of each wavelength accurately based on
Researchers develop LED covering full visible light spectrum Read More »
A good power supply is an essential subject to the microcontroller’s base project; it’s like a heart that gives a life to our microcontroller. Sometimes we take it for granted the important of having an adequate power supply to our microcontroller project and this can lead to the unexpected result or behavior from the circuit.
Powering Your Microcontroller’s Base Project Read More »
The Module-Driver Interface Special Interest Group (MD-SIG) has released its specification for a universal electrical interface between LED lighting modules and their power supplies. The standard has the support of Osram, Panasonic, Philips and Tridonic. Called LEDset1 edition1.0, it is a three wire interface (see diagram): power, ‘Iset’ and a return for both. The specification
Standard release for lighting LED-driver interface Read More »
Cree has added 50% more light output to its 3.5×3.5mm ‘XP’ format with the introduction of the four-junction XPH35 series. Something like 1,800 lm is available with the device turned up to its absolute maximum of 1.05A, when it typically drops something over 12.3V (~140 lm/W). At the specified current of 350mA (Vf ~11.3V) output
Cree squeezes 13W LED into XPH35 3.5×3.5mm package Read More »
Download the full package (micro code and PCB data) The core of this project is a PIC12F508 which was strictly picked based on cost and availability. This firmware should be easy to port to just about any PIC micro. Code only uses 1 timer, no interrupts, 22 bytes ram, and 369 words of flash. The
5 channel LED candle Read More »
There’s a new high-density class of CXA arrays from Cree that doubles the lumen density for next-gen LED spotlights. The CXA 1520 is the first HD Array announced under the breakthrough technology. It enables lighting manufacturers to create products that deliver the same intensity and light quality as 39W ceramic metal halide (CMH) at up
LEDs with double lumen density and 50% less power Read More »
The LEDactus is my version of a dry climate niche dweller like a cactus. LEDactus is immobile and attempts to survive by creating a pleasant display. This is of course in the hopes that passersby will be so entranced that they will build the LEDactus’ progeny. Initial generations create a simple but pleasing display. Later
LEDactus using PIC18F1320 Microcontroller Read More »
Finding a way to deposit vertical dielectric barriers has allowed Litecool of Sheffield to make dramatic cut in LED thermal resistance – from 1.25 to 0.5°C/W is one case – see diagram. Dielectric layers are essential to separate electrical conductors but, with a few notable exceptions like diamond, introduce thermal barriers. Spreading heat before it
Sheffield firm slashes LED thermal resistance Read More »
Arbitrary-beam headlights are another step closer, claims a German consortium. Cars already exist in which cameras shape the headlight beam around other road users – maximising light on the road while minimising dazzle. These adaptive headlamps are based on forward-facing cameras and shaped mechanical shutters within the headlight. With the advent of LEDs, headlamp developers
Germany takes a step to imaging LED matrix headlamps Read More »
