Philips Award Winning LED Bulb Review

ratsbew

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The Philips "Award Winning LED Bulb" is finally in stores and ready for purchase. The award that the name refers to is the Department of Energy's L-Prize which laid out standards for a "next generation" light bulb. Philips Lighting ultimately won the competition after meeting or exceeding all criteria and claimed a $10 million prize. At 94 lumens/Watt, this bulb is currently the world's most efficient A19 form factor bulb. The total power consumption is 10 Watts for a total output of 940 lumens. The estimated lifespan of the bulb is 30,000 hours which comes out to over 27 years when used 3 hours per day. Along with its very high efficiency, this bulb also boasts a color rendering indexof 92 which helps to ensure that colors are accurately rendered. The color temperature is rated at 2700K which is standard for incandescent bulbs and warmer than most LED and compact fluorescent bulbs.
http://i.imgur.com/J0aqR.jpg

Like Philips' first generation LED bulb, this uses remote phosphor technology to convert non-white light to white light. The first generation bulb used three blue LEDs behind each yellow plastic lens. This new bulb uses three blue and three red LEDs. This combination helps improve the color rendering index from 80 with the previous bulb, to 92 with the new bulb. After some prying, I was able to get the plastic lenses off to see what it looked like underneath.

http://i.imgur.com/bhGst.jpg

http://i.imgur.com/8uB6L.jpg
The smooth heatsink doesn't get very hot even after several hours of operation. It becomes too hot to hold onto for more than 2-3 seconds, but it is definitely cooler than many other LED bulbs that I have tested.
The blub is dimmable using leading-edge dimmers according to the box. I tested it out with a dimmer and found that it gives off a quiet buzz when on a dimmer even when at full brightness. The buzzing is probably loud enough to be distracting if you are using this as a reading light. On the subject of dimmability, I found that the bulb's light output becomes a very ugly color when dimmed. As you begin to dim, the light turns bluish and then it becomes pink. Overall, the dimming characteristics of this bulb are quite poor. My favorite dimmable bulb is still the Utilitech 60W equivalent.

The light output of the bulb is very good. The design allows light to be cast in all directions in a fashion similar to a standard incandescent bulb. Also, at 940 lumens, this bulb is one of the brightest available with the exception of Philips' own 75 Watt equivalent bulb that puts out 1100 lumens. The light quality at full brightness is good enough that nobody would likely suspect that it isn't an incandescent bulb if it is hidden by a lamp shade.
As for the design of the bulb, some will love it and some will hate it. The yellow plastic lenses on this new bulb are an ugly yellow in contrast to the nice golden yellow lenses on the first generation bulb. Personally, I think that is is cool looking bulb, but the first generation is much more visually appealing to me (the ugly yellow lenses are really quite hideous).

The initial retail price of the Philips L-Prize inspired bulb will be $50. Yes, FIFTY DOLLARS! The first generation 60 Watt equivalent bulb can be had for less than $25 now and I honestly would recommend it over this new "Award winning LED bulb". The old bulb puts out 800 lumens with 12.5 Watts of electricity. So, yes, it is significantly less efficient than the new bulb and the color rendering index isn't as good. Even as an LED bulb enthusiast I wouldn't spend $50 for this new bulb given what I know now about it. I hope that this review helps other LED enthusiasts decide to skip it. With luck, Philips will be forced to bring the price down when they realize that even the early adopters don't want it at this price.

So in conclusion, this is an excellent bulb if you need extreme efficiency such as in a hotel lobby or other places that have the lights on 24 hours per day. It will not only save on electricity, but also on maintenance costs to replace bulbs since at 30,000 hours of life it will take nearly 4 years of continuous use before they start to fail. For home use though, I would recommend the first generation Philips LED bulb since it is cheaper and still puts out plenty of high quality light.



Your images are oversize, when you post an image please remember Rule #3

Rule #3 If you post an image in your post, please downsize the image to no larger than 800 x 800 pixels.

Please resize and repost. - Thanks Norm
 
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Harold_B

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Thanks for the link and review(s). While I was there I read one of the GE posts as well. I hope you take this as it's intended and that's as constructive criticism but with the Internet full of bulb reviews from professional rags like EE Times and LED Magazine plus the DOE and IES testing it would lend more weight to your reviews if you listed your background and the test methods. If your review is purely subjective then that is fine but still toss out your background and the environment ou are using to assess the bulbs. It would belong on the review About page, not here.

Your writing style makes for an easy read which is a nice change of pace from "white paper" format. Nice looking site too. Thanks again for the link.
 

patrickhuang

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The smooth heatsink doesn't get very hot even after several hours of operation. It becomes too hot to hold onto for more than 2-3 seconds, but it is definitely cooler than many other LED bulbs that I have tested.
The blub is dimmable using leading-edge dimmers according to the box. I tested it out with a dimmer and found that it gives off a quiet buzz when on a dimmer even when at full brightness. The buzzing is probably loud enough to be distracting if you are using this as a reading light. On the subject of dimmability, I found that the bulb's light output becomes a very ugly color when dimmed. As you begin to dim, the light turns bluish and then it becomes pink. Overall, the dimming characteristics of this bulb are quite poor. My favorite dimmable bulb is still the Utilitech 60W equivalent.

The light output of the bulb is very good. The design allows light to be cast in all directions in a fashion similar to a standard incandescent bulb. Also, at 940 lumens, this bulb is one of the brightest available with the exception of Philips' own 75 Watt equivalent bulb that puts out 1100 lumens. The light quality at full brightness is good enough that nobody would likely suspect that it isn't an incandescent bulb if it is hidden by a lamp shade.
As for the design of the bulb, some will love it and some will hate it. The yellow plastic lenses on this new bulb are an ugly yellow in contrast to the nice golden yellow lenses on the first generation bulb. Personally, I think that is is cool looking bulb, but the first generation is much more visually appealing to me (the ugly yellow lenses are really quite hideous).

The initial retail price of the Philips L-Prize inspired bulb will be $50. Yes, FIFTY DOLLARS! The first generation 60 Watt equivalent bulb can be had for less than $25 now and I honestly would recommend it over this new "Award winning LED bulb". The old bulb puts out 800 lumens with 12.5 Watts of electricity. So, yes, it is significantly less efficient than the new bulb and the color rendering index isn't as good. Even as an LED bulb enthusiast I wouldn't spend $50 for this new bulb given what I know now about it. I hope that this review helps other LED enthusiasts decide to skip it. With luck, Philips will be forced to bring the price down when they realize that even the early adopters don't want it at this price.

So in conclusion, this is an excellent bulb if you need extreme efficiency such as in a hotel lobby or other places that have the lights on 24 hours per day. It will not only save on electricity, but also on maintenance costs to replace bulbs since at 30,000 hours of life it will take nearly 4 years of continuous use before they start to fail. For home use though, I would recommend the first generation Philips LED bulb since it is cheaper and still puts out plenty of high quality light.



Thanks for your sharing~

How does it make 100 .26 luminous efficiency(lm/w) at LM79 report ? it's an incredible specification , the 60w equivalent bulb is just 64 lm/w...
 

mds82

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I'm curious to see if you change the phosphor globe with the 2 versions to see what color light you get as a result. I would expect the more yellow colored phosphor on the 75 watt bulb to be cooler in color.
 

Kinnza

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Thanks for your sharing~

How does it make 100 .26 luminous efficiency(lm/w) at LM79 report ? it's an incredible specification , the 60w equivalent bulb is just 64 lm/w...

They got such improvement by changing the way of achieving the warm white tone. Instead of using blue LEDs and a remote phosphor which convert a large percentage to long wavelengths (red tones), in this lamp they used blue and red LEDs, with a remote phosphor which only converts to shorter wavebands (green and yellow). This solution is way more efficient than the older one.
 

hank

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Can you identify the wavelength of the 'blue' emitters? I wonder if they put out something into the ultraviolet range. ANy caution about taking the phosphor/cover layer off and exposing the bare emitters?
 

Yoda4561

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Damp locations too, a few of these might be nice for our older bathroom fixtures that seem to kill CCFL's on a yearly basis.
 

JohnR66

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50% more efficient than common spiral CFLs, CRI beyond 90 and expected lifetime better as well. While it won't sell at $50, you can expect when other manufactures figure out that blue & red LEDs with remote phosphor are a good way to go, there will be much more LED products coming later this year at better prices. In the next couple years, I expect 10 watt, 1000 lumen, 90 CRI bulbs for around $20.
 

Kinnza

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Can you identify the wavelength of the 'blue' emitters? I wonder if they put out something into the ultraviolet range. Ayy caution about taking the phosphor/cover layer off and exposing the bare emitters?

About 450nm peak wavelength, no any emission in the UV.

As with any powerful blue emitter, never look at it directly from close distance. But it is unconfortable well before the threshold for eye's damage, so actually your instintive reflex are protection enough.
 

Kinnza

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50% more efficient than common spiral CFLs, CRI beyond 90 and expected lifetime better as well. While it won't sell at $50, you can expect when other manufactures figure out that blue & red LEDs with remote phosphor are a good way to go, there will be much more LED products coming later this year at better prices. In the next couple years, I expect 10 watt, 1000 lumen, 90 CRI bulbs for around $20.

Fully agreed, actually there is some other brands releasing such bulbs right now, but emitting about 800lm instead of 900lm. In the next two years this level of performance should become very usual at much lower prices.

For the moment, at bulbs.com its at $59.99.
 
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About 450nm peak wavelength, no any emission in the UV.

As with any powerful blue emitter, never look at it directly from close distance. But it is uncomfortable well before the threshold for eye's damage, so actually your instinctive reflex are protection enough.


Any chance the red emitter is the 660 nm Rebel? That would be ... funny... given that there is a shortage of them right now.
 

Kinnza

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No, it is the orange Rebel. 660nm is deep red with very low photometric efficacy (little lumens produced), nobody uses it for human's lighting, as it adds little lm and just improve marginally CRI (if any).

Most solutions are using orange-red LEDs, with peak wavelengths below 620nm. Actually, LEDs spectrums are following the same path than fluorescents did, and almost all fluorescents today uses a peak between 610 and 620nm.

A paper about the "Brilliant mix" concept by Osram explain it very well. Its a very similar concept than the Cree "True White" and the used by Phillips in the L-Prize lamp.
 

blasterman

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About 450nm peak wavelength, no any emission in the UV.

The latest royal rebels typically have a dominant wavelength about 5nm shorter than Cree tends to run. May seem insignificant, but you can see the difference and I'm curious why Rebels have gone that direction. I would imagine the base of the bulb get's fairly warm.
 

Harold_B

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The Luxeon Royal Blue emission wavelength selection might be driven by the absorption spectrum of the phosphors they intend them to be used with. Not to be too picky but peak wavelength and dominant wavelength are not the same thing. I don't really understand why for some manufacturers the blue/royal blue LEDs or die are spec'd using dominant instead of peak wavelength.
 

Marcturus

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No, it is the orange Rebel. 660nm is deep red with very low photometric efficacy (little lumens produced), nobody uses it for human's lighting, as it adds little lm and just improve marginally CRI (if any).

Most solutions are using orange-red LEDs, with peak wavelengths below 620nm. Actually, LEDs spectrums are following the same path than fluorescents did, and almost all fluorescents today uses a peak between 610 and 620nm.
That's a business or engineering point of view, not an esthetical one. Your claim that "nobody uses" 660nm is exaggerated, of course. 80+CRI GE Vio used 660nm, and I happen to sometimes use 660nm LEDs for indoor residential lighting, when I don't add incandescent light anyhow.
 

Kinnza

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The latest royal rebels typically have a dominant wavelength about 5nm shorter than Cree tends to run. May seem insignificant, but you can see the difference and I'm curious why Rebels have gone that direction. I would imagine the base of the bulb get's fairly warm.

Osram took the same path. The reason after it is well explained in the paper I linked above. If you use a narrow peak on the orange-red, you need the green peak is on the short green, or the final solution falls off ANSI accepted white, is less efficient photometrically and have poor CRI. Osram addressed it by directly offering an special range of white (EQ white) intended to be mixed with orange-red. The phosphor converted white needs to be off the planckian locus in order the solution has good efficiency and final result is close enough to PL so it fall into ANSI specifications.

Phosphors has a broad Gaussian like spectral conversion, so if you want one with a peak at 550nm or shorter yet, its excitation band is going to be short too, usually with very reduced efficacy for blue over 460nm and optimal absortion about 440nm. Because that they are using deeper blues than for all phosphor converted white, where the longer blue works better (peak is on the green-yellow, overall CRI is better this way for this solution and blue adds more lm as longer its wavelength). Indeed, you can check how very often the warmer whites has blue chips with peaks at longer wl, up to 460nm.

The Luxeon Royal Blue emission wavelength selection might be driven by the absorption spectrum of the phosphors they intend them to be used with. Not to be too picky but peak wavelength and dominant wavelength are not the same thing. I don't really understand why for some manufacturers the blue/royal blue LEDs or die are spec'd using dominant instead of peak wavelength.

I would prefer too bins by peak wavelength instead of by dominant wl. But I understand dominant varies less with current and temperature than the peak so why manufacturers prefers it.

That's a business or engineering point of view, not an esthetical one. Your claim that "nobody uses" 660nm is exaggerated, of course. 80+CRI GE Vio used 660nm, and I happen to sometimes use 660nm LEDs for indoor residential lighting, when I don't add incandescent light anyhow.

You are right, it was an exaggerated statement. But it is a fact that it affects very little CRI while penalize hard photometric output so very little solutions uses it due the market focus on CRI for color quality. Violet based whites has been always marginal and only GE worked hard on it and it never was a sales success AFAIK. Apart of it, just very special applications, as lighting for red meat refrigerated stands and so are using deep red. In color rendering, it only makes a difference on the deep red tones. The color appearance of the light itself varies very marginally adding deep red, and except if very large amounts of it are used, little people is able to actually notice the difference.

Anyway, you can't use deep red alone, you need amber-red too or the color rendering is very poor, and that means 3 chip solutions. BTW, I too prefer this solution aesthetically for the best light quality possible, but I think we agree a 3 chip solution is less pragmatic for most situations.
 

Kinnza

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Interesting paper - Thanks for the link. I noticed one thing, listed under "Challenges" as "Color point stability". I assume it varies over the lamp life. Have you seen Philips measurements on color shift over the lamps 30k hour life?

I dont think there is such data yet, not enough time for that.

I believe the way Phillips manage it is by running LEDs very soft. At the current and temperature of typical operation, lm manteinance at 30Kh is going to be over 98%. The problem with long term color stability when there are no compensating electronics is the differential aging of red and blue LEDs, so by reducing the light emission depreciation they mostly avoid that issue.

The other problem is the color shift depending of temperature. I dont know if the L-Prize lamp has any electronics for compensating it. It is not difficult, Cree has used them on their range of fixed lighting fixtures, but maybe Phillips avoided it in this lamp and rely too on the low power per LED to minimize that shift. It would be interesting to check if CCT varies with ambient temperature and if so, by how much.
 
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