Is More Than 4,000 Lumens in a Single Package a Good Thing?

Posted: January 31, 2009 in Uncategorized

Luminus just announced the offering of  a configuration that pushes over 4,000 lumens in a single packaged device.  The company claims include the use of a Photonic Lattice technology to increase surface brightness and uniformity of the device. The result is a 6mm x 6mm area LED with exceptionally high output.

This all sounds great on the surface (no pun intended), and may be for a few special applications. Here is my own view of products like this:

First: 6,000K is not “cool white” it is beyond daylight white at best and has very limited usefulness for interior illumination.

70CRI is not good enough, period, no matter how much light is being cranked out.

The combination of 6,000K and 70CRI puts the application space for this product in factories, garages, outdoor areas, and warehouse locations, where cost will be a huge issue. The potential for long life may be its biggest asset here, in operational expense over higher maintenance HID products. However, this puts it squarely against 250W and 400W Metal Halide, and 50,000hr T5 lamp technologies – systems all producing well over 20,000 lumens, at very low initial cost.

+/- 32 lumens per watt efficacy is simply not good enough (assuming a raw 34 l/w at a power factor of 75% with a driver/power supply efficiency of 88% and ambient operating temp of 45C). This compounds the thermal design issues raised by its small size .

The package configuration and chip configuration will make optical design very difficult; reducing efficiency and demanding large total package size, further limiting its application potential.

The heat sink required for products like this will be huge, confounding product packaging, on top of the optical design configuration.

The power supply/driver requirements will compound all of the packaging issues – not to mention the cost of development.

The luminous intensity of a 4,000 lumen device in such a small space is simply dangerous to human vision. This is exactly the focus of emerging regulation by ANSI on the safety of LED devices. This will make optical design an even larger problem, likely resulting in even lower applied efficiency.

The poor efficacy seems to indicate that while the lattice technology offers improved uniformity, their is no additional extraction from the LED die themselves that is not already happening with other methods. If there was indeed greater extraction to gain the higher brightness, efficacy should be higher, not lower, than others using the same internal LED die.

Against an HID source of 70 lumens per watt, in a luminaire of 50% efficiency, the Luminus package is essentially an equal, offering only a longer life for its extra cost (will require 5 units to equal a 250 MH lamp). Against a 50,000 hr XL T5 fluorescent lamp of 90 l/w, in a luminaire with 65% efficiency, there is no contest, the T5 wins. Efficacy is a problem, a big problem. Likely, the optical design around it will result in efficiencies around 80% at best, resulting in applied luminaire efficacy that is lower than incumbent low cost products offering better color and simpler packaging. This will make development of finished products that produce strong cost justification positioning very difficult. Unless maintenance or the cost of failure is very high, this is going to be virtually impossible. The markets for low CRI products that are not concerned with CCT are predominantly cost driven, where decisions are made with little or no design input – not a great space to place high end products with minimal efficiency.

All that said, this is but one step toward what will eventually become a tool in the lighting toolbox. If this were producing 70 lumens per watt and 5,000 lumens, at 4,100 CCT, and 80 CRI, the lighting universe would be freaking out and doing hand springs.  The fact that the CB-360 is roughly 70% of the way toward this goal is amazing, and a real indication of what is coming. At the pace of development of LEDs, one could realistically expect that within 18 months, efficiacy improvements, CCT improvements, and CRI quality improvements will occur that put a device like this squarely in the center of general illumination. At that point, everything from outdoor area lighting to interior general illumination will be in play. The increased efficacy will shrink the thermal problem in half, and the color will be tolerable. Now, add some new product designs that put that 6 x 6mm luminous source to work in truly new lighting solutions (I can think of several that will change the way we light space with a package like this), and you will have the home run of the century!

Until then, all I might offer is khudos for the effort thus far, and good luck. In projector, theatrical, and other highly specialized applications, this is a great product and excellent progress. In the long run, this is certainly a company and product worth keeping an eye on. There are others in this field, slowly but surely creeping up on this from the deep recesses of labs around the world:

If you are looking for killer power, nothing reaches the heights of the Kiss! products at 500W and 20,000 lumens, any color and high CRI.

Enfis. These guys have the color thing nailed to the wall. Intensity as well, including a 4,000 lumen array. On top of this, Enfis offers full color, white light engines that can be run from <3000K past >6000K, at over 90 CRI, and very high drive currents.

Kiss! GmbH. Want lumens? These folks got lumens, 20,000 of them at an efficacy of around 40 l/w using W/G/B/R/Y die, color is excellent as well. In Frankfurt, they presented their 500W device in a display they required you wear welding glasses to view – now THAT’s power!

These are just the scratches in the surface of high power LED products to come.

In the meantime, medium and high brightness LEDs today are reaching efficacies, and color performance that are just starting to make a dent in general illumination. There is still a lot to be accomplished at the sub-micro-star level of performance. These higher output products have a place today in some very specialized applications, that will grow into the lighting market as costs and performance continue to come together.

  1. kwillmorth says:

    Jon Connel wrote the following:

    I must confess, when I first saw these new high Output Luminus Devices (LD) products I was first struck by the mechanical design. I thought to myself – “wow, it looks almost like a new lamp type”.
    Hold on though…
    To explain myself a little – I come from a classic electronics educational background, but have spent the last 25 years in the lighting industry designing lighting fixtures. I “get” electronics; I know lighting.

    I always say that we lighting types should never forget that we are fundamentally working in the construction industry. Much as people like myself would have the world believe we are rocket scientists (and some of us in lighting even are), in the end our product needs to stand next to other equally hardworking engineer’s products – concrete, rebar and galvanized junction boxes to name but a few. Pick up a 200 watt Metal Halide lamp and you have something that Joe the Plumber won’t accidentally snap the pins off while reading the sports pages at the top of a ladder on the jobsite on a rainy Monday morning.
    It has consistently irked me since I first picked up a white Nichia LED in the late 90’s that LEDs are so “electronic” in design. What commercial lighting needs is something “electrical” in design. There is a difference…

    I immediately noticed the relatively massive Amp Stakon type quick disconnects attached to the MCPCB and corrected myself “its not a lamp it’s a filament” . Very close to what I have been dreaming of – a lamp component building block that I don’t need an electronics assembler to make work.

    Actually its not, but its close. The quick disconnects are there to handle the huge current these little monsters draw. I hear that the Avnet sales team actually pushed the factory for an interconnect solution that worked without soldering. That’s good thinking on their part – the average lighting manufacturer still struggles with solder and pcb headers and a product which we can connect easily on the bench is a huge step forward. These new products are in fact closer to the perpendicular mount projection LED boards (Osram / LD) than they are to my personal dream of an LED lamp building block / LED filament. The whole “electronicness” (sorry) of most packaged LED solutions is still miles away from what an industry that is used to arcs, filaments and tubes needs. This LD product is a step in the right direction.

    If I was a product manager at an LED manufacturer today I would pass on the Lumens / Watt chase for 9 months and work on my packaging and interconnect solutions. That would generate way more dollars than 10 more Lumens / Watt in a package ever would. Electronics connectors and solder connections are off-putting to engineering vp’s everywhere – we all trust what we know. I have no idea what the ideal solution would be, but putting some good minds together on the problem would be a start.

    Don’t get me wrong… I don’t want a lamp, I want a filament.
    A type lamps look like A lamps because that’s the best possible 3d footprint you could put a hot filament in at the time. Fluorescent lamps are long thin white tubes because they make more light and last longer that way. Ditto that thinking for HID lamps. Fixtures in turn are the shape they are because a good fixture designer always starts with the source and then wraps the enclosure around it to meet the performance and protection requirements for the project. I don’t want a lamp – that will come over the next decade without a doubt. What I want is a “filament” that some clever minds can then start thinking about pins, lamp envelope, interconnect and lamp holder solutions for – to make an analogy to conventional terminology. Until the LED packagers start thinking along those lines and – over the next decade – start to standardize some of my putative filaments into commercially useful parts we fixture designers will never have the analogous lamp to wrap our fixtures around.
    It’s a series of linked steps that define each other – Filaments, arcs and tubes,>> define capsules,>> which define lamp bases,>> which define lamp holders,>> all of which define fixture form. Its that simple. It’s a birthing process and one we really need to get on the stick with here in the US. We know we need to retrofit these parts at some point – so why not start with a plug in part now? That’s what we excel at in the US after all – process and method driven design. Kudos for the connectors LD.

    I spend a lot of time making my MCPCB designs multi-package capable, future field serviceable and while doing it, try to predict what my market will want 2 years downstream and at the same time what direction the LED packagers will move in. On Friday afternoon this week I was prototyping with some new Seoul LEDs. I had a magnifying glass, a jewelers loupe in one eye and the smallest soldering iron tip money can buy. I burnt myself and found two LEDs in my trouser cuffs when I got home. Difficulty in handling is an impediment to development. I do not believe things have to be this way if we fixture people get together and ask for it. Whatever the future brings, you know it will not be a 9 position gold plated Tyco pcb header – Joe the Plumber would think that’s girly for sure.

    This is definitely not a problem you will have with the LD product. This thing wears Steel toecap boots. You will however have a few other problems on your hands as follows.

    From a light generation point of view this is definitely step forward and in my opinion has its uses. When my Avnet guy showed them to me I immediately thought of HID replacements – high bay and parking lot fixtures, commercial signage etc. The CBM-360 White, 6000k, 4250 Lm and a CRI of 70 definitely puts them out of most architecture and display markets. It certainly packs a punch though.

    No, the Lm/w numbers are not great, but I quit worrying too much about those numbers about 6 months ago when the customers – rightly or wrongly – stopped asking questions and decided that LEDs in the main are more than efficient enough already. I don’t think I would have any problems designing an optic to make this work in the above listed applications – I haven’t tried it yet though…

    These are not cheap parts. I would need to look very carefully at margins on comparable Lumens using multiple devices + mcpcb / driver / optic combinations before I took this to my management. Generally less is less, so a single part could well be lower in cost in a finished fixture design than using multiples of another flavor. The integration of a thermocouple in some of the LD products is nice – now add R,G,B photodiodes to the RGB product please and you really have my attention.

    Power supplies and cooling are big issues here, especially for low-tech manufacturers with minimal in-house engineering resources. Power supplies to match these devices are not something that you can get off the shelf – as far as I know – and would need some not too trivial design work to make happen. There are then multiple code implications arising from the power levels. Something a lot of people are not aware of is that the three largest testing agencies here in the US each interpret the most common UL listing number impacting LED fixture driver and power labels in a different way. Long story short at least two agencies in the US are going to UL test a fixture with a single piece of the LD high power product as if it were a line voltage fixture. This has both lead time to market and cost implications and severely limits the materials selection and housing construction options for the fixture.

    Lastly, as Larry Boxler points out so elegantly, you need a big fat heat sink to make these perform.
    I designed with a 200 Watt Enfis RGB+ LED in 2007. The heat sink was so large that it completely redefined the nature of a lighting fixture. I have clients who are looking at the Edison 50W and 100W products – I hear there is also a 200 Watt from them, but I have never seen it. You run smack dab into the same design issues – a fixture that no longer looks like what Joe public expects a fixture to be. Fun for the designer, but a real concern for marketing and investors..

    In the end that’s all part of the same birthing process I mentioned above – re-engineering our customer’s expectations of what a fixture is while we re-engineer the product to fit around our evolving source.

    This source has definite merit in certain applications.
    Either way good to be talking about something other than Lumen improvements for a change – bring on the next round LD.

    Jon Connell, IESNA-NYC

  2. Seema says:

    sta kon terminals
    The information u shared i very usefull and i follow it.

  3. I would like to know what size the dissipator should be. Maybe army tank size?


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