LFI report, part 3: LED technology, outdoor lighting (MAGAZINE)

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This article was published in the July/August 2011 issue of LEDs Magazine.

View the Table of Contents and download the PDF file of the complete July/August 2011 issue.

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LFI report, part 1: Linear LED lighting, OLED and planar lighting

LFI report, part 2: Retrofit lamps, modular SSL

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Section 5: LED technology

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The LED technology that underlies innovative SSL products was also on full display at LFI. As mentioned previously, Philips won an LFI Innovation award with its Luxeon A family. Perhaps the most notable LED trend is the combination of red or amber LEDs with white LEDs to more-efficiently produce warm-white light. In its TrueWhite-based lighting products, Cree has used sensors to monitor the white and red emitters to detect differences in lumen depreciation and adjust drive current accordingly. The company has now decided that the sensor is not needed, eliminating it in the previously mentioned CR linear fixture. Cree’s VP of research and development Paul Pickard said, “Our longevity data indicates similar depreciation rates in both colors of LEDs used in Cree TrueWhite technology. This allows us to design fixtures that maintain their specs, over their lifetime, with no adjustments.”

SSM-80 LED from Luminus Devices

Luminus Devices has been best known for its self-proclaimed big-chip LEDs, but at LFI moved to a smaller emitting area with the launch of the 1600-lm SSM-80 LED. The new LED offers a tighter beam and will target applications such a spotlights used to illuminate retail merchandise. Luminus’ Chuck DeMilo said customers can more easily design drive circuits for the new LED. The device actually uses four emitters in series yielding a 12V stack that requires 1A in drive current. That’s more in line with LEDs from other vendors whereas the Luminus SST-90 product, for example, requires 3.2V and 3.2A.

Bridgelux ES Star Warm White

Bridgelux continues to ride improvements in its LED technology to offer brighter products in smaller packages, announcing the third generation of the LS, ES, and RS LED-array families at LFI. The benefit according to VP of global marketing Jason Posselt is better efficacy and lower cost. Generally, Posselt said the second-generation products offered 75 lm/W in luminous efficacy at $0.013-$0.015 per lm. The new products take efficacy to 90 lm/W and cost under $0.01 per lm. As to how the gains were made, Posselt said, “It’s a sum of epi, chip design and packaging.” He noted that a close examination of the LEDs would reveal that “we’ve added some extraction features to the silicone-coated phosphor on the arrays.”

Osram Brilliant-Mix technology

Osram Opto Semiconductors launched its own Brilliant-Mix technology at LFI, utilizing white and amber Oslon SSL LEDs to generate warm-white light. Osram is advocating the use of a sensor to monitor the different LEDs, thereby ensuring consistent brightness and color. Brian Terao, director of SSL, believes that customers will relish the choice of optimizing a design for efficacy or cost. He said the Brilliant-Mix will yield better efficacy, although the sensor will make it more expensive. Osram said Brilliant-Mix will deliver 110 lm/W in luminous efficacy – 30% higher than can be achieved using warm-white LEDs with similar CRI and CCT.

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Section 6: Outdoor lighting

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The established players in LED-based outdoor-area lighting were all present at LFI, most of whom utilize relatively-small LEDs mounted on a circuit board in an array, and total-internal-reflection (TIR) optics on each LED to form a beam pattern. It’s generally been considered problematic to control the light from larger LED sources although such sources could offer advantages in outdoor lighting since many such applications require significant light output. LFI witnessed more luminaire makers using larger sources. For example, Eagle Eye Lighting demonstrated lights that use its retrofit module based on larger Bridgelux arrays and reflectors that form the desired beam pattern.

BetaLED LEDway SLM

BetaLED stuck with smaller emitters in the new LEDway SLM and LEDway SLM IP66 products launched at LFI. If a street light can be called elegant in terms of looks, then the SLM is the one. SLM stands for single light module and as the nearby photo shows the fixtures are rather sleek-looking relative to the more typical rectangular or cobrahead lights. BetaLED says that the products can replace 70-250W high-pressure-sodium lights. Certainly the development of the SLM products was enabled by significant industry gains in LED brightness.

GE Evolve series luminaires

GE Lighting is the one established player in street and area lighting that has utilized reflector technology broadly in its outdoor LED product line. The Evolve family typically includes one or more closely-grouped arrays of LEDs mounted within circular or rectangular reflector structures. At LFI, GE announced new Evolve series luminaires for area-light, flood-light, garage-light, post-top, and roadway-light applications. The Contemporary Conical luminaire pictured is designed for post-top use and offers a 60% reduction in energy consumption compared with typical HID lights, according to GE.

Eye Lighting KiaroLED area light

Eye Lighting has boldly entered the market with its KiaroLED area light that is the first product to use a TIR approach with larger LED sources. The product is based on Luminus Devices’ SST-90 LEDs. To eliminate light losses caused by the Etendue effect, the TIR must be quite a lot bigger than the source resulting in a 0.75-in-diameter TIR according to Eye Lighting VP of lighting Rob Freitag. The luminaires use 6 to 9 LEDs in linear or rectangular arrays depending on the prescribed beam pattern, whereas outdoor lights based on smaller emitters often use 20-60 LEDs.About the Author

LFI outdoor sessions address best practices and MLO

The Lightfair International (LFI) conference program featured a broad set of classes and sessions, and several addressed outdoor lighting in general, whether the light source was LED-based solid-state lighting (SSL) or legacy lamps. Sessions on best practices and the new Model Lighting Ordinance (MLO) stood out, providing key information on glare, the human visual system, and lighting levels that balance visibility and minimal light pollution.

In the outdoor-lighting area, Ray Grenald and Mark Harris of lighting firm Grenald Waldron Associates presented “Street and area lighting around the world – reducing energy, carbon emissions and light pollution while maintaining quality of life.” The session proceeded informally but provided a series of lessons that could easily be the basis of a best-practices guide.

Inconsistent global regulations

Harris lamented the lack of consistency in lighting regulations around the world. He said that Ottawa, Canada city code prescribes brightness levels that are 50% of Illuminating Engineering Society (IES) recommendations whereas the nation of Qatar in the Middle East prescribes double the IES recommendation.

The pair are generally in favor of less light at night, and suggested that too much light can reduce safety. Grenald said, “You can inadvertently put more light on the pupil causing it to close and you get less light in the back of the eye.” In such cases visibility is reduced, and glare is often the issue.

Harris said, “The key for me is more fixtures and greater control.” But of course more fixtures would drive costs up. Still there are other ways to improve lighting with the knowledge of the human visual system. Harris said, “We see brightness not foot candles and we see more vertical brightness than horizontal brightness.” Again glare from high angles is a major concern.

Grenald also addressed the need for security lighting in applications such as college campuses. He said, “Don’t make it brighter like most people do, but light the bushes and trees at a low level.” His point was to light places where a predator might hide.

Model Lighting Ordinance

Nancy Clanton of lighting firm Clanton & Associates also addressed outdoor lighting and specifically the MLO that the IES and the International Dark-Sky Association (IDA) have jointly developed. Some have seen the IES and IDA as having dueling goals, but Clanton said, “There really was a cohesive common goal.” Clanton said the organizations were seeking to minimize excessive light to save energy, improve the enjoyment of the night sky, and minimize the impact on bio-cycles of people and animals.

MLO sample table

At LFI Clanton said the MLO release was imminent and it has in fact been released to the public as of June 14. The goal was an ordinance focused on lighting first rather than energy. It is meant to apply to lighting applications such as monuments, signs, water features, and seasonal, landscape, emergency, and temporary lighting. Generally the target is lighting on private property. The MLO exempts street lighting although it can be adopted by small communities that lack the engineering resources to create their own street light regulations.

The MLO is defined by a series of five zones that are designated LZ0 through LZ4. Clanton said LZ4 is for places like Las Vegas or Times Square and “is not recommended for most cities.” LZ0, conversely, prescribes no constant ambient lighting and the use of motion sensors. Ultimately the success of the MLO will depend on city planners that make the right decision in choosing the appropriate zones and enforcing the MLO. The easiest way to learn more is to visit the IDA web site. Clanton said that Plymouth, MN and Anchorage, AK would be the first cities to adopt the MLO.

About the Author

LFI shows LED skeptics remain and OLED still trails

While the show floor was brimming with LED-based luminaires and lamps, Lightfair International (LFI) sessions demonstrated that skepticism still lurks over solid-state lighting (SSL). OLEDs were also highlighted on the show floor, although an expert panel focused more on the roadblocks that limit the technology to decorative lighting for now.

There were numerous LED-centric sessions at LFI, but one entitled “LED performance: Myths and facts – an LED industry report card” served to remind that SSL is a relatively new technology. Indeed presenter John Curran of consulting firm LED Transformations took a skeptical approach in his session that seemed targeted at newcomers to SSL. And clearly despite the prevalence of LED technology at LFI, the technology is still new to some lighting designers, architects, building owners, and municipalities.

Component and luminaire life

Curran described known issues with LEDs in lighting such as component life and the need for thermal management. He presented a case study detailing LEDs that maintained L70 (70% of initial brightness) for 148,000 hours when the junction temperature was maintained at 55°C whereas the useful life dropped to 67,000 hours at 85°C.

Philips 75W-equivalent LED lamp

Curran also addressed LM-80 testing and misconceptions saying, “If someone tells you LM-80 is indicative of LED life, they are wrong.” He said LM-80 only tells you how to take the measurements. He expects the TM-21 standard for predicting lumen maintenance to be more valuable saying, “TM-21 will tell you how to connect the dots.”

Not all of Curran’s comments were skeptical. He told the audience that if you buy LED products from a reputable manufacturer that other components would likely fail before the LEDs. But Curran also warned the crowd about the realities of the market discussing retrofit lamps and the consumer market. He quipped that if he bought a $40 LED bulb, “I’m going to keep the receipt for a while.” His actual point was that residential customers are far more upfront-cost conscious than commercial customers, and residential customers look for much faster payback periods preferably inside one year. That could make residential a tough market to crack.

OLED lighting potential

While LEDs have become the workhorse star of LFI, OLEDs remain the technology of untapped potential. The “Creating a vision for OLED lighting session” allowed proponents to once again discuss that potential. The session featured Acuity Brand executives Jeannine Fisher and Peter Ngai, lighting designer Patricia Glasow, James Brodrick from the US Department of Energy (DOE), and consultant Paul Burrows of Reata Research.

Acuity Kindred OLED luminaire

Acuity clearly intended to use the panel to promote its investment in OLED technology and the introduction of the Kindred and Revel OLED fixtures at LFI. Burrow did the heavy lifting in the session providing a relatively complete explanation of how OLEDs work.

Burrows acknowledged the Acuity OLED announcements saying “Before today, there was no real OLED lighting product on the market.” What he didn’t say was that Acuity won’t ship the OLED products until next year and they are likely to be below the 100-lm/W efficacy threshold that most experts believe OLEDs must reach to serve in mainstream lighting. Acuity hasn’t released full specs for the OLED fixtures, but in the OLED session Fisher argued, “60 lm/W is the entry point for being able to mainstream OLED lighting.”

Burrows was probably more candid than Acuity would have preferred in his other remarks. He said that you can easily make decorative OLED fixtures today, “but that won’t save energy.” His point was that OLEDs will have to replace ambient and task lighting for there to be a compelling energy-efficiency story.

Panel efficiency research

In his role at the DOE, Brodrick is squarely focused on energy efficiency. And he said that efficient lighting needs to address “panels rather than pixels” – thus his continued interest in OLEDs as a planar source. Indeed OLED projects won more than $4.8 million of the $14.8 million in R&D funds recently awarded by the DOE.

Burrows did note several potential OLED advantages. He said that OLEDs need simpler driver electronics than do LEDs, and with OLEDs the device efficiency is the luminaire efficiency. He also said that OLEDs will better deliver warm white light.

Still Burrows noted numerous roadblocks. He said today only 20% of the light escapes an OLED source without out coupling. There are also dispersion-pattern and substrate issues. All of the roadblocks can be overcome but for now manufacturing costs that are too high. He said cost today is $50 per square meter and that needs to drop to $20 or less.

Glasow chose to focus purely on the aesthetic advantages that OLEDs offer. She noted that the technology offers better RGB color mixing than LEDs. And she said, “OLEDs let you get rid of those heat sinks.” But clearly energy efficiency and cost will gate wider deployment, and we will wait yet another LFI cycle or more to witness clearance of those hurdles.

About the Author

Barbapapa Light

credmp posted a photo:

To make it easier to look at my son without turning on the big bad lights we bought him a LED based barbapapa.

Barbapapa is both the title character, and name of the “species” of said character, of a series of children’s books written in the 1970s by Annette Tison and Talus Taylor, who resided in Paris, France. The books were originally written in French (barbe à papa is French for cotton candy, or—literally—”father’s beard”), and were later translated into over 30 languages. As short cartoons of a length of only five minutes, they reached a broader audience via TV. Also a comic book version was created. Both the cartoons and comics sometimes show concerns about the environment and contain environmental messages.

Uglyworld #1233 – Ugly Towers At Nights (Project BIG – Image 230-365)

Project B.I.G. – Image 230/365

Withs me beings away so muchers since we movered intos the new cookie cave as I likes to callers it, the one thing I has been missering mega muches is the awesomer Ugly Towers, insides which I renters a roomer with somes of my coolers friendlies.

I deciders to shows you a litter of how mega coolers the towers looks at nighters when we fires up the LED lighterings that Baz installeds for us.

At the moments it’s probablies a gooder idea that I is travellerings so much as the amounts of roomers is getting mega limiteds in all three towers, so I has appliereds for plannering permissions to gets Ugly Tower #4 buildered, hopefullies it gets approvered so we can all has plenties more spacers.

Sunwayman V10R Ti

wuyeah posted a photo:

“China makes crap” it is true in some areas but in flashlight making Chinese factories have been taking more than few notches up in quality. Number of companies such as 4Sevens, Fenix, JetBeam, Nitecore…name a few all making top notch quality flashlights. Of course they are not Surefire but they are not asking Surefire prices too.

My newly arrived Sunwayman V10R Titanium is perhaps one of the best looking 1 cell battery flashlight on the market. Titanium case body with CREE R5 LED. 210 lumens (1.5hr) on high output with Infinite Variable Output ring to 1 lumen (35hr). It is not the most powerful single cell battery flashlight but ain’t it a beauty.