newsletter link
mondo arc
MONDO ARC

A new era for lighting

Issue 55 Jun / Jul 2010


Dr Geoff Archenhold casts his eye over the latest LED and OLED launches at Light + Building.

This year’s Light+Building will most likely be remembered more for the volcanic eruption in Iceland and tales of how weary travellers made it back to various parts of Europe, rather than the eruption of change seen in the lighting industry. It was clear from the first day in Frankfurt that the lighting industry has changed for good and significant battle lines are being drawn between technologies, companies and indeed sectors. Despite a lengthy 18 hour trip back to the UK by train, taxi and coach it was certainly worth the effort along with the other 180,000 visitors.
After five days of visiting the show there were five key themes that stood out:

1. LED lighting was the dominant lighting solution.
2. Significant progress was made on OLEDs.
3. LED Retrofit bulbs will make a significant impact on our daily lives very soon and it will be dominated by the big organisations.
4. A shift will happen over the next five years from traditional western lighting brands to global consumer electronics brands from Asia.
5. The price:performance ratio for LED lighting will rapidly reduce over the next two years despite short term supply chain issues.

I was fortunate enough to meet with several leading players as well as a few entrants within the European lighting industry to discuss how the lighting industry is going to look by 2015. This month’s article will cover the general consensus of what the market will look like along with a selection of the most interesting products launched at the show.

LED Lighting dominates
Light+Building was dominated by LED products with only a handful of manufacturers deciding not to show LED related offerings. The majority of the LED lighting launched was of a bulb retrofit basis. However many of the traditional lighting companies demonstrated both CFL recessed downlights and street lighting technologies.
It is a testament to the rapid improvement in LED efficacy (due mainly to the scientists and engineers behind the scenes) that LEDs have become the future of lighting for volume white light applications. A few years ago in this very column I predicted that LED bulbs would be available in retail stores at pricing that would ensure mass market adoption by the London Olympics and it was very clear this will now be the case. Several manufacturers including GE, Lighting Science Group, LG, Philips, Panasonic, Toshiba and various others are now investing significantly to develop and market their retrofit bulb ranges.
It is clear from walking four or five halls at the show that one of the greatest challenges facing lighting designers and end users is how best to choose LED products that are high quality and reliable. Many of the CEO’s I managed to interview all expressed a concern of possible user and designer backlash from sub-standard products over the next 18 months. The key issue cited by the larger companies was that LED bulbs all appeared very similar in style so it wasn’t very clear to end users how to determine if a particular product used quality components and all aspects of thermal management was properly designed.
I believe this issue is going to be a major barrier that the lighting industry is going to have to self-regulate through developing standards and active policing on quality and safety, or else the lighting industry’s reputation will be tarnished by failing LED products. Unlike previous market perception problems suffered by technologies such as CFL, LEDs have a lower cost and technology barrier to the market which leads to significant numbers of LED products being sold, so the light source is not dominated by a handful of manufacturers that could control quality. The second issue is that traditional light sources’ lifetime performance was mostly set by the lamp manufacturing process whereas LED fixtures have many links in the chain that can degrade fixture quality and performance including poor thermal management. 
I will cover some of the interesting product launches later in the article, but let’s turn our attention to the LED emitters and light engines on show.

LED Emitters and Light Engines
As one would expect there was a significant number of new LEDs being demonstrated at Light+Building. Here are my highlights:

AC LEDs – rapidly developing
Although AC LEDs have been around for a couple of years (see my previous article on the mondo*arc website), they are now starting to show a degree of maturity with development from companies such as Seoul Semiconductor exhibiting impressive performance. The big news however was that Philips Lumileds has now decided to enter the AC LED market with their own new AC LED product range due for launch later in 2010.

Seoul Semiconductor exhibited the latest Acriche A4 that has a luminous flux of 83 at a power of 0.83W and a CCT of 6300K providing a 100 lm/W efficacy. The new Acriche A4 uses a different type of manufacturing process from previous A3 emitters overcoming many of the issues including dimming with earlier products making the technology much more efficient and useful in real applications. The A4 is very compact in size with a footprint of 7mm x 7mm x 3mm. The warm white version of the A4 has a typical CRI of 85 at a CCT of 3000K with a typical 50 lumen output at a power of 0.76W providing 66 Lm/W efficacy.
The Acriche production is currently ramping up to produce a 100 lm/W version by the summer of 2010 with mass production of 150 lm/W being scheduled to begin by the end of the year accelerating the replacement of halogen lamps, incandescent light bulbs and fluorescent lighting with LED technology. Certainly, at 150lm/W even in cool white, the Acriche technology will find a place in many applications where simple LED drivers are required.
In addition, Seoul has also launched the 1W A6 and the 4W A7 Acriche emitters -  both in a small footprint compared to the previous generation of 1W and 4W emitters. The A6 and A7 will use the new production process that enables the die to be reduced down so the A7, at 8x8 mm, offers space-saving versatility over current 18x12 mm Acriche products.

A new entrant to the AC LEDs world is Philips Lumileds who launched the Luxeon Rebel AC which will be available in full production by the end of 2010. This is a radical departure for Lumileds who create the original high power DC LED die that has revolutionised LED lighting. However, a key advantage of the new AC LED is that it is in the same Rebel form factor and package architecture ensuring the thermal management is of high quality.

The key points highlighted by Lumileds include:
• 60 lumens/W typical
• 2700 and 3000K CCT
• High current efficacy
• Excellent hot / cold factor
• Proven reliability
• Exceptional color stability
• Superior lumen maintenance

Philips Lumileds states that it has an advantage over its main competitors because of the die architecture it uses as shown in figure 1. The Rebel AC uses one large die which is in a flip chip format so there are no bond wires required and is directly mounted on a ceramic/silicon submount rather than a sapphire substrate thus improving performance. 
The foray into AC LEDs by Philips demonstrates a new strategy which is probably a sign that LED bulbs will need a different approach than just standard DC LEDs. One of the difficult issues with LED retrofit bulbs is squeezing an LED driver into such a small area and then adding a high temperature environment up to and in excess of 100°C making them unreliable at best. Thus, by using an AC LED for these applications it reduces the complexity of the driver saving space and getting rid of lots of unreliable components.

Everlight also demonstrated its Action series AC LEDs with up to 68 lm/W efficacy in 2W and 4W packages both in 3000K and 5700K colour temperatures. The AC LEDs are available in 100V, 110V, 220V and 230V AC ratings.

DC LEDs continuing efficacy and CRI
DC LEDs are not quite finished yet and Light and Building saw many new LED emitters launched with ever higher efficacy and improved CRI efficiency.

Firstly, Philips Lumileds displayed the new Rebel ES available initially in Cool and Neutral White CCT’s with a minimum lumens per watt efficacy of 120 lm/W producing 120 lumens at 350mA and 108 lm/W with 225 lumens at 700mA. The preliminary specifications for the new Rebel ES are shown in Table 1.
The interesting points to note is the new ES has a much lower forward voltage than most white LEDs and the typical voltage at 350mA is 2.85V rather than the 3.15V. Launch for volume production is anticipated to be sometime in summer 2010.

Everlight from Taiwan introduced the new 3W Shuen LED family (see figure 3) offering a slim package (3mm x 4.5mm x 2.2mm), high power and high luminosity for advanced lighting applications. The 3W LED can deliver up to 170 lm/W at 700mA and has the flexibility of various CRI (Color Rendering Index) with 75 and 90 depending on their lighting applications. The new product will be available from August 2010.
Everlight has also developed the 5W Yi (6mm x 6mm x 4.28mm with 4 LED die) and 10W Tsan (10mm x 10mm x 5.15mm with 9 LED die) LED Emitter packages that offer higher wattages in both Cool and Warm white colour temperatures. The Yi offers a minimum luminous flux of 375 lumens at 700mA in Cool white whilst the Tsan delivers 625 lumens at 1050mA in Warm White.

Avago announced the release of a 3W LED emitter shown in figure 4 with dimensions of 5mm x 4mm x 1.85mm thick packaged in a 6-leaded small outline package (SOP) and capable of being driven to up to 700 mA. By delivering a high flux output with a minimum of 100 lumens at 350mA driving current, the ASMT-Jx32 provides a wide viewing angle of 140-degrees to meet the needs of designers who require good colour uniformity. Avago’s 3W emitter is a high performance LED designed to handle high thermal and high drive currents. The ASMT-Jx32 features a maximum allowable junction temperature of 135°C to provide greater design flexibility to the lighting designers. The LED is encapsulated in a heat and UV resistant silicone material and features a low thermal resistance of 9°C per watt due to its superior heat dissipation capability.

Sharp supplemented its LED lighting portfolio with three new white ‘high colour rendering’, high-performance LEDs. The ‘DoubleDome’ LEDs shown in Figure 5 already provide suitable light for energy-efficient lighting without secondary optics.
The light conversion layer of the ‘DoubleDome’ LEDs is based on a two-phase development procedure especially developed by Sharp for this purpose. A layer of phosphorous for the conversion of white light is applied in a first step. The installation of the globe top made from transparent silicone in a second step makes light extraction possible without spreading loss. Sharp’s breakthrough ceramic substrate achieves high reliability and heat dissipation.
The high colour rendering LEDs reach the high CRI value of 85 through the combination of blue LEDs with a special blend of green and red phosphorous to deliver up to 54 lumens in a 0.8W package. The SMD LEDs from the new GM2BBxxBM0C series ensure high colour fastness with typical applications for high colour rendering LEDs including photography, retail lighting and in medical applications.
As different applications also require different lighting concepts, the ‘DoubleDome’ series is available in three different Colour Temperatures, starting with ‘Warm White’ at 3,000K, and ‘Natural White’ with 4,000K to ‘Pure White’ with 5,000K as shown in Table 2. In combination with the high CRI values, the new LEDs from Sharp are approximately equivalent to conventional fluorescent tubes with regard to their efficiency, colour temperature and colour rendering index (CRI). Sharp’s ‘Double Dome’ LEDs, are compact in a package only 2.8mm x 2.8mm x 1.9mm in size.
With such a high CRI the 3000K LED provides approximately 58 lumens per watt, the 4000K approximately 60 lm/W and the 5000K approximately 64 lm/W. It may seem that the efficacy is low for CCT values of 4000K and 5000K however this is impressive when you take into account that it is for a CRI of 85 which is difficult to achieve at such colour temperatures.

Verbatim is a well known brand in the IT world and many of you may remember it from the 3.5” floppy disk era. However the owner of Verbatim, Mitsubishi Chemical company (MCC), has announced they are going to enter the LED market in 2010.
Mitsubishi Chemical, manufactures both phosphors and LED chips and has decades of experience in these technologies but they are looking to develop a new generation of LEDs, planned for 2011, that utilises a violet light emitting chip with red, green and blue phosphors. These products, also in warm white, will offer further improvements in CRI with a typical average value of 98 providing an industry leading figure. A further advantage of using a violet LED with three part phosphor (shown in figure 6) is that lighting fixtures can be made colour tunable with a high CRI from 2700K to 5500K without significant loss of lumens per watt across the colour temperature range.
Interestingly, violet LEDs with multipart phosphors do not require binning because the output is not dependant upon the wavelength variations of the LED as found with standard Blue LEDs with yellow YAG phosphors.
Providing these new Violet based LEDs come to market with efficacies between 60 lm/W and 70 lm/W in 2011 then they could provide a compelling offer although violet LEDs have never managed to break through into the marketplace.

Cree announced a breakthrough new lighting-class LED platform, the XLamp XM LED. This new single chip LED delivers record-breaking efficacy of 160 lumens per watt at 350 mA. The LED also delivers 750 lumens at 2 A, which is equivalent to the light output of a 60W incandescent light bulb at less than 7 watts. The thermal resistance of the XM platform is 2 degrees C per watt — an industry-leading technology breakthrough and a 350 percent improvement over Cree’s flagship XLamp XP-E LED. It is estimated that the XM LED will be available sometime in the Autumn.
The XM LED emitter family will provide an acceleration of LED technology away from traditional light sources enabling LED fixtures to compete with even high flux CFL based products. For example, a 2000 lumen LED downlighter could be manufactured from just three XM LEDs at 2A!

The Bridgelux Array platforms were demonstrated within the Helieon module (Figure 7) designed for high light output applications including retail, street, wide area, high bay, and commercial lighting. The Helieon lighting system is the first plug-and-play, sustainable solid state lighting module to integrate high-efficiency precision lighting with an easy-to-use socketed solution to accelerate innovation and enable the mass adoption of solid state lighting. The Bridgelux arrays were used by Manor Group to replace 50W halogen light sources in their Zurich store to good effect as shown in figure 8 whilst reducing energy consumption by over 50%.
The Helieon modules offer uniform high-quality illumination with beam control optics (24, 32 and 50 degree options), High system efficacy enabling luminaires with operating efficiencies of >50 lm/W and colour controlled to a single 3-step MacAdams ellipse.

OLEDs make an increased presence
Light+Building marked a significant showing of various OLED companies all demonstrating products at a variety of technology readiness levels. What was impressive was the number of OLEDs being demonstrated and the focus being placed on the technology.
I have followed OLED technology for more than ten years and I strongly feel that OLEDs are a technology waiting for an application but it is not displays or lighting. However, many of the companies I spoke with think my view is wide of the mark and OLEDs are ready to launch into the lighting market within a few years.

Verbatim will launch its OLED offering in 2011 and is a solid-state semiconductor device composed of ultra thin films of organic molecules that create light. Multiple times thinner than a human hair, OLED lighting can be made flexible and as light as a feather. Mitsubishi Chemical Corporation (MCC) has decided to use the unique qualities of OLEDs, integrating them into printable hole injecting material (HIM) with newly researched light emitting technology. This allows the mass production of the world’s largest class of lighting area, about 14cm square.
Lighting fixtures based upon MCC OLED technology will offer high quality colour lighting with dimming and full colour tuning capabilities. Verbatim has a variety of quality OLED products on show (see figure 9) and what was impressive was the size and colour consistency of the panels as with most OLED systems they use small areas of OLEDs but the Verbatim products were significantly larger than most. Interestingly, Verbatim have partnered with another leading Japanese brand, Pioneer, on OLED production.

Novaled demonstrated a complete booth of OLED type fixtures and light engines providing a very high quality light with a CRI of up to 95. A range of OLED lighting from warm white to clear cold white was also exhibited including colours such as deep orange, rich red and intense blue. Colour tunable OLEDs which cover a broad span of colours from light blue through clear white and all the way to orange were also be launched.
The OLED devices which are manufactured on glass and metal substrates, are extremely thin, lightweight and come in various sizes from 25sqcm up to 225sqcm active area. Depending on the substrate material and device structure chosen, OLEDs can be transparent, have a diffuse appearance or behave like a mirror in the off state.
For Novaled’s commercially available OLEDs (up to 15x15 cm active area) they currently confirm around 20 lm/W efficacy although Novaled are part of the www.oled100.eu consortia who are developing an OLED panel with the target specifications in Table 3.

LEDON OLED Lighting, a division of Zumtobel, demonstrated the LUCEOS OLED lighting series, a combination of a new lighting technology and innovative integration solutions for future lighting applications. The LUCEOS OLED lighting series is based on the ORBEOS CDW-031 OLED elements fabricated by OSRAM Opto Semiconductors.
The ORBEOS OLED panel has a round lamp surface of 79mm diameter and is integrated into a hexagonal mounting system which includes an electrical and data bus system for maximum flexibility in large areas. LUCEOS OLED lighting series offers a reliable contact configuration and robust housing by ensure a thin profile of about 6 mm.
The mounting system for LUCEOS lighting modules offers secure magnetic holding to easily replace OLED lighting modules. Additionally it allows easy chain connections to establish large area fields which offer a large area aspect ratio with over 80 % effective lighting area fill.
In addition to the LUCEOUS LEDON demonstrated the LUREON OLED lighting series which combines high area aspect ratio with a slim form factor and excellent optical properties to achieve large area lighting. Again, the mounting system is based on the patented housing and holding system and includes an electrical and data bus system for maximum flexibility in large areas.
The LUREON OLED lighting systems offer different rectangular form factors, at the beginning two standard sizes (100x100mm and 50x100mm) are available. The OLED panels allow the realization of high quality lighting systems with colour rendering indexes over 80 for natural colour representation.
Also the New Energy and Industrial Technology Development Organisation (NEDO), (www.nedo.go.jp/english) funded by the Japanese Government, had an all OLED Booth showing over ten different products from companies such as Panasonic and NEC. The projects ranged from OLED modules through Chandeliers and downlights to a really cool OLED window which offers 80% light transmittance when switched off so you can see through very clearly.

Of course Philips were demonstrating their OLED panels which did seem to have a slightly better illumination quality than the majority of OLED panels. However they were in a much smaller form factor.

GE, a major Lighting force, showed off their latest OLED panels that were 75mm x 150mm in size and offering 28 to 30 lumens per watt in high CRI and various CCT versions. The research and development partnership between GE and Konika Minolta seem to be bearing fruit as 30 lumens per watt is a step further than most OLED manufacturers can achieve. GE believes that they will have a significant lead compared to other OLED entrants as they will produce the OLED panels on a roll-to-roll process similar to newspaper printing which will enable them to produce high performance, low cost devices when commercialisation starts next year. Most of the other manufacturers OLED panels are produced using a different technique which spins or vacuum coats a glass or plastic plate, which is more expensive and time consuming to produce.

Despite the increase in presence of OLED manufacturers the technology is still in its infancy with low lumens per watt efficacies, high costs and a raft of production issues still to be overcome. However, I think OLEDs will definitely become the next big technology for lighting at the next Light+Building in 2012.

The battle of the LED bulb
Although the OLED market is dominated by large players from both the traditional lighting and consumer goods sector, the real battle is beginning within the LED retrofit bulb arena. As previously described, LED retrofit bulbs are very difficult to manufacture reliably because they have a limited space envelop in which to dissipate heat and that usually translates to poor optical performances compared to traditional light sources and decreased reliability because of high driver temperatures (one reason why AC LEDs may dominate the retrofit sector). However, the battle lines are being drawn up between traditional lighting companies like GE, Philips and OSRAM and new global brands including Panasonic, Toshiba, Verbatim as well as smaller LED companies such as Lighting Science Group.

Verbatim’s retrofit LED lighting will be available in wholesale and retail outlets throughout Europe by the end of 2010.  Initially, the company plans to sell lamps with many of the most common shapes and base fittings including A-lamps, candle lamps and directional MR16s, with a choice of E14, E27, GU5.3 and GU10 bases to follow later. The products will be suitable for direct replacement of incandescent and halogen lamps with typical energy savings up to 80%, compared with conventional lighting. The products will have lifetimes of around 35,000 hours depending on operating conditions.
The first family of lamps will be based on a blue light-emitting chip LED technology. They will be competitively priced, available in cool and warm white, and have a typical colour rendering index (CRI) similar to that of other products currently in the market. The next generation of lamps, planned for 2011, will use a violet light emitting chip with red, green and blue phosphors. These products, also in warm white, will offer further improvements in CRI with a typical average value of 98.  
 
Toshiba officially entered the European lighting market with the launch of the E-Core LED product line, consisting of lamps and a high-efficiency LED downlight fixture line. The lamp line, which includes six reflector lamps in three colours and two A19 bulbs in two colours, features high brightness and energy efficiency in compact designs. The downlight line includes six models available in four colours, in which the brightest model reaches a luminous flux of 1250 lumens.
Toshiba is also demonstrating several technology prototypes including LED bulbs with a 1690 lumens performance and a 260-degree lighting angle, and GX53 self-contained round units with a total luminous flux of 2000 lumens. Other prototypes feature surface-mount ceiling lights that integrate a high-efficiency LED and a power circuit that produces 120 lm/W, and LED flood lights that can light up tall buildings and bridges with the same central luminosity as metal halide lamps.
The LED retrofit bulbs, see figure 11, are offered in a variety of lumen outputs however the 2700K 9W lamp offered 600 lumens providing an impressive efficacy of 67 lm/W whilst the 4000K 9W version provided 78lm/W. More impressively is that these total flux measurements were taken after the light bulbs had been switched on and off 40,000 hours. The LED light bulbs also have a minimum 80 CRI.
Toshiba also demonstrated the LED Downlight 2000 which has a diameter of 169mm and height of 79mm. The 2700K, 26W produces 1295 lumens (~50 lm/W) whilst the 4000K counterpart produces 1460 lumens in 26W (~56 lm/W). Toshiba representatives stated that pricing will be very competitive and emphasized that Toshiba have a strict quality control process ensuring user reliability.

Panasonic also launched its LED bulb retrofit range with high efficacies. The LED bulb LDA7L-A1is 107mm long and 55mm in diameter with a CCT of 2700K and up to 40,000 hours lifetime. The bulb produces 360 lumens by using only 7W of power to give 51 lm/W efficacy whilst the 6700K version produces 460 lumens or 66lm/W.
In addition to the LED light bulb replacement, Panasonic has launched its GU5.3 and GU10 LED retrofits. The warm white MR16 version has a 2700K CCT and provides 150 lumens in only 4W providing 37.5 lm/W increasing to 50 lm/W for the 3000K version. Panasonic stated that Lifetimes for the MR16 range is 25,000 hours.

GE also launched its LED GLS Lamp consuming only 9 Watts of power and providing a true 360 degrees of light output mimicking a standard 40W lamp. The new light bulb shown in figure 12 will be in US stores from August 2010 and the LED bulb produces 450 lumens for a total of 77 percent in energy savings. Unfortunately, the price looks to be in the $40 to $50 range and provides 25,000 hours of light. GE are using the Cree-XPG LED emitter in the new lamp. The GE Energy Smart LED bulb look ultra cool with external fins that cradle the diffuser while performing a cooling function: they’re connected to the LEDs inside the bulb to draw heat out, keeping the LEDs cool to ensure a longer life and greater efficiency. The fins also keep the surface of the bulb cooler than comparable incandescent bulbs.

Lighting Science Group from the US also launched the DEFINITY line which is a 9 watt LED A19 bulb which will retail in the low $20 range (~£13) and is a direct replacement for 60 watt incandescent bulbs. The DEFINITY LED bulb provides a stunning 770 lumen output which is 80% more efficient than a 60 watt incandescent bulb, will last close to 23 years and provides 85.5 lm/W in warm white variants. This new LED bulb seems to be a significant step ahead of the competition in both technical and commercial offerings and this has been validated by the largest home retailer in the USA, Home Depot, who will retail the DEFINITY later this year.

Philips also demonstrated the Endura LED retrofit lamps, see figure 13, which provides up to 806 lumens in a 12W package (~67 lm/W) equivalent to a 60W lamp. In addition, the use of a new design and remote phosphor technology delivers the same soft white light and shape consumers are familiar with in an incandescent and it will work with standard dimmers. The EnduraLED will be available in the fourth quarter of 2010.

Conclusions
Light+Building demonstrated that it is possible to deliver quality LED retrofit lamps in different formats. However it is clear that this market will be dominated by the global players from lighting and consumer electronic goods - the new Japanese electronic giants - as they have the experience and know-how to displace market leaders in sectors that are being disrupted. For example one only has to look at the TV market where GE and Philips dominated less than ten years ago which is now led by companies such as Panasonic, LG and Samsung.
Therefore, I think the LED lighting industry is going to become very competitive within the next two to three years which can only be good for lighting designers and consumers.
The price is reducing and the performance increasing of LEDs with improved lumens per watt efficacies planned for 2010 and high CRI LEDs being freely available. This new LED technology will ensure LED fixtures will exceed 100 lumens per watt and pass that of even the most efficient fluorescent tubes.
In the next edition mondo*arc I will cover all the latest LED news and discover the vast array of LED products being launched at the Guangzhou International Lighting Exhibition.


If you would like to know more about any aspects of the LED sector then please send your questions or comments to me at g.archenhold@mondiale.co.uk

 

Figure 1: LUXEON Rebel AC architecture


  • Figure 2: LUXEON Rebel AC circuit diagram


  • Everlight 3W Shuen Series


  • Figure 4: Avago ASMT-JX32


  • Figure 5: Sharp DoubleDome

  • Figure 6: Verbatim Phosphors

  • Figure 7: Bridgelux Helieon

  • Figure 8: Bridgelux at Manor Group's Zurich store

  • Figure 9: Verbatim OLED

  • Figure 10: Novaled Enspiro OLED fixture for Trilux

  • Figure 11: Toshiba LED bulb

  • GE LED GLS bulb

  • Figure 13: Philips Endura LED
Related Articles

SEARCH

Follow us on…

Follow Mondo Arc Magazine on Twitter Follow Mondo Arc Magazine on Facebook Follow Mondo Arc Magazine on Linked In





mondo arc india









darc awards DWLF IALD PLDC LRO