I am excited about this product, and I am not the only one. The US department of energy is excited about it, and so is Phillips, and rightfully so. The holy grail in home lighting is solid state, and this is the first truly acceptable replacement for the incandescent lamp. It's merely a light bulb, but this is a revolutionary device.Up until now, the reference standard in lighting was incandescent. What makes the incandescent lamp so good is the quality of light that comes from it, the fact that there is no warm up period and that it is subjectively pleasing. What is not so good is that the incandescent lamp is wasteful and most of the energy it consumes is converted into heat and not light. The bulbs don't last very long, and even though the bulbs themselves are inexpensive, they consume a lot of energy.CFLs are better than incandescents in the aspect that they are very efficient, and can be tuned in order to make light that approximates warm incandescent light. They, however, do have a warm up period, and flicker at a very rapid frequency. Some individuals are sensitive to the flickering, and even `warm' CFLs are subjectively more harsh that incandescent light. During the warm up period, CFLs are dim.CFLs also can have a very long life. They function best when they are left on most of the time, but with frequent on and off cycling this life is reduced. They also contain a nominal amount of mercury, and responsible disposal of CFLs should include recycling in order to keep the mercury out of landfills.The Phillips EnduraLED A19 bulb contains no mercury (if that is important to you), but what makes it so revolutionary is the quality of the light that it produces. There is no warm up period, although there is a brief start up lag from the moment a light switch is thrown. Some have complained about this, I do not find it to be bothersome.I have been using this bulb for about a month, and also have used the 16 watt, 75 watt equivalent A21 bulb. In use, it just works and is indistinguishable from the incandescent equivalent. It looks unconventional when turned off, but I find the appearance pleasing and high tech looking. In use, it simply looks like a bright light bulb, albeit with three heat sinks that divide the bulb into three wedges. This is only evident when looking at the bulb itself, and the light that is produced is indistinguishable from an incandescent bulb.The use of high power white LEDs is well established in flashlights, and are wonderful in that application. There is, however, no LED that will produce white light directly. The way the white LEDs work in flashlights is that they use blue LEDs surrounded by a phosphor applied directly to the bulb. The blue light excites the phosphor layer, which then emits brilliant white light. The light is very directional, which is great for a flashlight, but not so much in a light bulb. The other problem is that LEDs are inherently very intense light sources, and produce a fair amount of heat from a small source. In white LEDs, over time this will chemically degrade the phosphor layer which will become more opaque and reduce the performance of the bulb. Phillips takes a different route and separates the phosphor layer from the LED by placing the phosphor in the shell of the bulb. This prevents the phosphor from being exposed to the most direct heat, and also distributes the phosphor over a much larger surface. All other LED lightbulbs that I have seen use white LEDs with directly applied phosphors, and attempt to prevent phosphor degradation by various cooling schemes. One very hyped company has liquid cooled white LEDs, but good luck buying one. Phillips has been manufacturing state of the art white LEDs for a long time in their Luxeon line, and went to a lot of trouble to avoid directly applied phosphors.The EnduraLED bulb solves both the directionality of the LEDs and also helps prevent the degradation of the phosphors by using a remote configuration. The phosphor layer is separated by the light source, and thus the most intense heat, by being contained in the yellow panels that make up the outside of the bulb. The yellow panels that are seen when the light is off become intensely white when the bulb is on, and cast bright, omnidirectional white light.The US Dept of Energy established the ten million dollar L prize to encourage development of a more efficient, market acceptable lighting technology. Phillips won the L prize with a 10 watt 60 watt equivalent bulb. The EnduraLED A19 is not the bulb that won the prize, but incorporates a lot of the technology that went into the winning design, and uses only 2 watts more.Is this the perfect light bulb? Unfortunately, it is not. First of all, and the hurdle that most will encounter in adopting them in general use, is that the bulbs are quite expensive at about $40 anywhere you look. (Edit: I saw the bulb on Home Depot's website today for $25. Guess I was wrong, the cost can come down...) Every review I have found discussing these bulbs mentions this problem, and most express the hope that the cost will come down significantly. To be honest, I don't know how much the cost can come down. One very noticeable aspect of the bulbs is that they are quite heavy, and there are heat sinks built into the "bulb" part itself, and the shaft of the bulb which contains the electronics. There is a review which can be found on the internet in which one of these bulbs what taken apart, and the build quality is incredible. Perhaps if the bulbs are used extensively, economy of scale will bring the price down somewhat, but don't expect to find these bulbs discounted anytime soon. EDN did a teardown of the bulb, and you can see the build quality but I cannot post a link here. "EDN LED light bulb reveal different design approaches" in google will find you the article.One other concern I have about the bulbs are the fact, like all white light LEDs, they rely on phosphors, and I wonder if the phosphor layer will give the service life that Phillips promises they will. I emailed Phillips about this question, and according to them, because of the remote phosphor configuration, the heat the phosphors are exposed to are much less and they will not degrade the way directly applied phosphors will. Time will tell, I have been using the bulbs for a few months now.I have converted most of my home to CFL lighting already. CFLs work, even if they don't always give the promised service life. CFL lighting is harsh in my opinion, so in areas that I considered lighting quality critical, such as bathroom mirror fixtures and in dining areas, I continued to use incandescent lights because I felt it was worth it. This light bulb changes that, and I am converting those light quality critical areas to these light bulbs now. Given the expense, and since I am not in a position to go to the store and drop a couple hundred on light bulbs, that means I buy one more bulb here and there. Ultimately the bulbs will pay for themselves in energy savings, and the light is beautiful.
| (customer reviews)
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