Philips LED bulb Tear-down

http://www.edn.com/blog/PowerSource/40512-Remote_Phosphors_Philips_LED_bulb_Tear_down_Part_II.php

by powertower • 15 years ago

116 69 15 years ago

deweller• 15 years ago

I would love to see something like this on the new Switch bulb coming out (supposedly) this fall. More info on the Switch bulb: http://www.slate.com/id/2298444/pagenum/all

ErikRogneby3• 15 years ago

Hell of a lot of components for a light bulb. The joys of achieving feature parity with the (150+ year old) incumbent product/technology.

owenmarshall• 15 years ago

I'd be interested in seeing what lightbulbs looked like if we designed them from scratch today -- without, as you note, 150+ years of expectations and needs.

What could they do that the traditional old incandescent can't? What would they look like?

On a more general note, does this "design in a vacuum" have any valid applications? Can this lead to ideas that we can use today, or is it just pie in the sky thinking?

ristretto• 15 years ago

Well the bulb shape is really a relic from the past. The design has already been disrupted with fluorescent lights, that brought bigger cylindrical shapes that diffuse more.

ErikRogneby3• 15 years ago

It might look like this: http://www.adafruit.com/products/357 - Buy your lighting by the foot. 12V DC may make more sense for homes these days than 115 AC. The incandescent bulb was the "killer app" for a whole power ecosystem. In older houses in places like San Francisco you sometimes find wiring going through the old gas lamp lines.

Alex3917• 15 years ago

"I'd be interested in seeing what lightbulbs looked like if we designed them from scratch today"

The problem is that humans have coevolved with both sunlight and fire. While the shape of the lightbulb may be arbitrary, I think the fact that they provide uneven lighting and cast all sorts of shadows is probably necessary for good mental health. (Because it provides more sensory stimulation, and more closely mimics the natural environment as compared with what you would get from evenly distributing LEDs across the ceiling.)

bryanlarsen2• 15 years ago

Perhaps even more interesting would be "what would they look like if unconstrained by technology"? A lot of science fiction proposes the uniformly glowing ceiling. This would provide a very consistent & uniform light without the eye strain caused when you look directly at a point source.

Another common idiom in science fiction is to replace your windows with giant transparent television sets, functioning simultaneously as window, television, telephone, artwork and light bulb.

ChuckMcM2• 15 years ago

Lots of good suggestions here. GE has 'light panels' [1] and one of the things which I am sure we'll see for 'installed' lighting will be 'sky ceilings' that would be a ceiling covered with OLED panels arranged seamlessly which mimic the 'sky' when you are outdoors, providing night views with stars, twilight colors, etc. Probably won't be the 'common' implementation however.

Generally I think one thing that will survive will be 115V ac power distribution. Its got a lot going for it in terms of installed base and understanding its transmission properties. The means LED based lighting will always have some circuitry to rectify and regulate that voltage. Of course they may evolve so it rectifies it to 135v dc and then runs off that.

I enjoyed the psychology comment as well. There were some comments that gas didn't give that 'homey hearth fire' smell when burned back when people were switching from wood fireplaces over to gas.

Even without constraint, I think you will find lighting fixtures don't change too much. You've got area lights and directional lights. The designers will have fun with them, glowing coils, maybe pillows that glow. But a good reading light puts out a uniform beam of light that can be directed easily to your lap. A good area light provides a widely dispersed light without being impossible to look at. Those constraints won't change because the technology has.

[1] http://www.ge.com/products_services/lighting.html

cjdavis• 15 years ago

Meanwhile the >75% reduction in power usage and >800% increase in lifetime are features that have surpassed the incumbent (which are what makes the $40 cost affordable - a feature they are no where near approaching..)

jonknee• 15 years ago

Parity? It uses less energy, exhausts less head and lasts orders of magnitude longer.

marshray• 15 years ago

But even parity was not achieved by CFLs, particularly for dimmable applications. It seems like the latest generation achieving parity (where the CFLs failed to) with the century-old technology is the notable point, more so than by how much they surpassed it.

If that makes any sense.

ErikRogneby3• 15 years ago

Required parity features: bulb form factor, warm white light, dimmable, runs off 115V AC source, screws in to existing sockets. Feature enhancement: long life.

digikata• 15 years ago

For all the complexity, it's a lot more efficient. Some of the complexity problem comes from adapting LED to design decisions made for incandescent AC lighting in the switches, dimmers, sockets, and power supply. If it were worth it for the user to rewire their house, they could likely get overall simpler and more reliable LED lighting.

There's a parallel to software design, one often incurs complexity when optimizing or adapting one software approach to another. The system might be more reliable overall if you can re-align the entire design, but there's a cost involved in it that might not make it worth it (particularly for physical things with replication costs).

pilgrim689• 15 years ago

Here's another feature an LED light bulb offers: high-bandwidth data transfer.

http://www.ted.com/talks/harald_haas_wireless_data_from_ever...

maukdaddy• 15 years ago

Does the use of connectors imply that users could replace failed LED boards instead of trashing the entire bulb? Or even upgrading to more efficient LED boards?

sixtofour• 15 years ago

I'm sure it's no usable serviceable parts. The article's author had to destroy the bulb to get in and take pictures.

ChuckMcM2• 15 years ago

It means its possible, it doesn't mean that the owner could do it. It would be good PR on phillip's part to include a postage paid mailing label that would let you recycle dead bulbs. They could recover most of it and save both e-waste and the energy cost of casting a new heatsink.

ars7• 15 years ago

The energy cost of individually mailing a heavy bulb is greater than the energy cost of casting a heatsink.

Centralized recycling might work, but not a postage paid mailer. Plus who is going to successfully store a mailer for 10 years while waiting for the bulb to burn out.

And in 10 years they won't want this bulb back, there won't be anything reusable in it. Just recycle it for the metal.

nate_meurer5• 15 years ago

This is a brilliant idea. Absolutely brilliant.

My biggest reservation about buying LEDs now isn't the price; it's that the lights that will be available next year will be twice as good, and I can't stand the thought of discarding an entire bulb in order to upgrade. It makes no sense to me that the actual LED is inseparable from its quarter-pound aluminium and plastic shroud. A lightbulb should allow you to swap out some small component that includes the LED die and perhaps the driver.

ars7• 15 years ago

When compact fluorescent bulbs first came out they did something like this.

The ballast lasts much much longer than the bulb, so you were able to remove the bulb while keeping the ballast.

It was a total failure. And in hindsight a terrible idea.

No two companies' bulbs were compatible so most of the time you were not able to find a replacement bulb even if you tried, and when you could find them they cost more than an entire new bulb!

The reason is that the extra cost of manufacturing them in a replaceable fashion costs more than simply tossing them.

I can confidently predict that you will never swap any components from a commercial LED bulb.

And BTW the "LED die and perhaps the driver" is probably 95% of the cost of the bulb. The heatsink and housing is nothing in comparison. There is nothing of value in them to keep. Just recycle them for the metal.

weeny6• 15 years ago

It's definitely not user serviceable. Indeed, the SMPS circuitry at the base of the bulb is going to fail before the LEDs do, and that stuff is all encapsulated in epoxy.

probablyrobots• 15 years ago

ianaee, but the board from the led bulb looks just as hand soldered as the board from the cfl. I don't think the following argument holds up very well.

"I was quite impressed by the use of connectors in this bulb rather than relying on low-cost-labor for hand-soldering which has been used in the manufacturing of CFLs."

bryanlarsen2• 15 years ago

Daniel_Newby provides an alternative explanation: that it's wave soldered.

http://news.ycombinator.com/item?id=2860140

weeny6• 15 years ago

The Rebel LEDs can't be hand soldered or wave soldered. They are reflow soldered. You can do this with a toaster oven.

jim_h3• 15 years ago

The LED technology used in that bulb seems a little dated. I believe it's using Phillips' Luxeon Rebel LEDs.

Looking at the pictures, there's 3 sections and each section has 6 Rebel LEDs. Total of 18 LEDs. All for output of 800 lumens.

A recent LED flashlight can produce 800 lumens with just 1 (CREE XM-L) LED. For example, http://www.fenixlight.com/viewproduct.asp?id=141 If you want a warmer white tint, it's a little less lumens, but you can always use 2 LEDs..

LEDs have come a long way in the last couple of years. It's just unfortunate that light bulb manufacturers do not make and sell new models as quickly as flashlight companies. There seems to be a new model every week with the latest LED for crazy light output.

Another example, http://www.fenixlight.com/viewproduct.asp?id=149 It does over 2,000 lumens with 3 LEDs!! This is just one company. There are many more that also have crazy flashlights.

If you want to learn more about LEDs or flashlights, head over to http://www.candlepowerforums.com/vb/forum.php

ars7• 15 years ago

The reason they are so bright is they don't need to worry about color accuracy. I bet these bulbs are very blue.

Also, their efficiency is about 57.8 lm/w which isn't very good (it's not terrible - but once you try to get a good color the efficiency drops a lot). http://www.wolframalpha.com/input/?i=800+lumens+%2F+%288*250...

weeny6• 15 years ago

They aren't blue at all, they are 2700K - and this is a big part of the reason they are 57.8 lm/w. The remote phosphor, while creating a very uniform photometric distribution, reduces the overall light output by filtering the very monochromatic blue light into warm white light.

mixmastamyk• 15 years ago

From the article it appeared that the selling point of the bulb was omnidirectional light at a certain power. In that case a large number of weak leds makes sense.

weeny6• 15 years ago

Philips updates the technology in the Rebel LEDs several times a year. In fact, they have on several occasions demonstrated record-breaking output in this form factor up until earlier this year.

The reason that flashlights are updated so much more frequently than light bulbs is that flashlights don't require any consumer safety ratings. Where a company can release a battery-powered flashlight with no safety testing, a light bulb running on line voltage has to be brought through a rigorous UL, CSA and FCC standards compliance testing.

jim_h3• 15 years ago

Yes, you are correct. I overlooked that important fact. It'd still be nice if they moved faster.

euroclydon• 15 years ago

Anyone know what this comment means:

Incandescent technology is still superior to any other lighting tech, especially solid state. When one factors in laser sintering of incandescent filaments that increases their efficacy to 3-5 times even LED's, incandescents absolutely rule when considering their performance and cost of production/recycling/logistics/..ect... I love bandgap technology, but it will be hard pressed to beat Edison's brilliance (it hasn't been done yet, despite articles such as this one).

nate_meurer5• 15 years ago

It means nothing. LED lighting is still an infant technology. Any shortcomings are a moving target given how fast the technology is progressing.

The reference to filament sintering is incorrect. First, it's not sintering, it's a process applied to a filament after is has been drawn. Second, the efficiency gain is around double, which still can't even come close to LEDs. Look here for a bit more:

http://www.rochester.edu/news/show.php?id=3385

The reference to "production/recycling/logistics" is also wrong if it refers to the EROI of LED lighting, which has already bettered that of incandescent lighting:

http://www.osram-os.com/life-cycle-assessment

ck2• 15 years ago

As previously seen on HN http://news.ycombinator.com/item?id=2845306

Note this is a $40 bulb. And it doesn't come with a 20 year warranty, the circuit could fail in a few years and then you've got one expensive lump.

angusgr• 15 years ago

This. In particular, I'm concerned by the little switchmode power supply on a non-user-servicable board potted into the depths of the bulb.

If that 5c capacitor dies, a $40 bulb gets scrapped even if everything else is still good. Hopefully Phillips have designed around that, but 20 years is a long time and they have little incentive to do so.

I suppose a proper, universal, standard for low-voltage DC in houses (ala 12v Halogen downlighting only universal, something like PoE) is probably too much to hope for.

Cushman2• 15 years ago

I wonder what the actual color temperature of the "blue" LEDs is— I've been hoping for a while that the rise of LED lamps would finally mean shifting to more natural colors.

It's kind of absurd to me that in this day and age we're still trying to make our artificial light look like another kind of artificial light rather than sunlight.

(For reference, daytime sunlight is around 5500k— these bulbs are marketed as 2700k, which is about the color of sunset, sunrise, or a large fire.)

ars7• 15 years ago

That's because we like the color of fire and always have. The lux from the sun is so high that the color temperature doesn't matter except in photos.

Cushman2• 15 years ago

Always have... since the invention of controllable fire by nearly anatomically modern humans? I'm skeptical.

For the entire history of human evolution since the formation of the Earth, that color of light has meant it's almost, or just was, night, and was strictly transient. Just 400,000 years ago it also started meaning that it is night. And just in the last couple of hundred years, with industrialization, it's become the color that most of us see most of the time.

Now, I'm not saying that's necessarily bad— but you gotta wonder why.

jim_h3• 15 years ago

The cool (bluish) white tints of LEDs usually produce the most lumens. As you go to a neutral(5000k) or warm(around 2700k) white tint, the lumens output is lower. I assume they went with a cooler tint to get the most output.

LED production has improved a lot recently and now it's possible to select the exact color temperature of the LED you want to buy. Also, it's now possible to get the same output (800lumens) with only 1-2 LEDs and have a good color temperature without extra steps.

nate_meurer5• 15 years ago

The issue isn't so much the color temperature; it's more about overall color rendering. Black-body radiation, like we get from the sun and incandescents, provides the best color rendering across the whole visible spectrum, assuming a color temp somewhere near the middle.

CFLs aren't too great at rendering, because their phosphors emit very spiky output.

LED phosphors are improving rapidly in this area.

phaker• 15 years ago

> For reference, daytime sunlight is around 5500k— these bulbs are marketed as 2700k, which is about the color of sunset, sunrise, or a large fire.

Cold light will mess up your sleep patterns:

http://en.wikipedia.org/wiki/Circadian_rhythm#Light_and_the_...

(unfortunately I can't find a better source)

nitrogen2• 15 years ago

So you use a varying color temperature and brightness throughout the day/night cycle.

dpark• 15 years ago

There's a big difference between cold light a neutral light. Personally I hate "warm" bulbs. I use the "natural" bulbs which to me appear not cool but neutral. I've read that asian nations also tend to use much cooler bulbs and dislike the warm ones, but I can't find the reference now.

Also, according to your Wikipedia article "Lighting levels that affect the circadian rhythm in humans are higher than the levels usually used in artificial lighting in homes".

weeny6• 15 years ago

AFAIK the blue LEDs used in these remote phosphor applications is 550 nm "royal blue" monochromatic chip; you can buy these chips on their own, and they are some of the highest energy output chips available on the market.

juiceandjuice3• 15 years ago

Does anyone know where you can get the phosphor plastic they use in these?

weeny6• 15 years ago

It is a plastic resin that has been blended to a precise dosage with YAG phosphor. You can buy YAG phosphor easily from wholesalers, for example, phosphortech, a Georgia company, sells a variety of colors of phosphor. However, the trick is to precisely and uniformly blend it in with the plastic resin - the reason that it takes so much time and development money to make a light bulb like this.

juiceandjuice3• 15 years ago

Nice, who do you work for?

dhughes• 15 years ago

Another thing to consider is other than LED being so much more complex compared to a glass bulb with a tungsten wire in a vacuum is why a bulb?

We have been limited to bulbs why not lighting in sheet form or around the edges of rooms rather than a point source in the middle of the ceiling?

I know manufactures have to be backwards compatible but in the future it would be nice to have the option of a different method to light an area.

Philips LED bulb Tear-down

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