Over in a salt water forum I submitted some 10watt Chinese LEDs so a member could test them with a spectrometer, and the results compared to base Cree's were pretty made for the Chinese tech. Compared to XT-Es the popular SEMI based Chinese LED that's rampant on Ebay is maybe half as efficient. If you'd like to challenge those conclusions be aware you are on the wrong side of the facts.
Given the fact that the market for cheap emitters is based on price and not performance there's no need for the Chinese to 'up' their technology. Cree, Bridgelux, Luxeon , etc., are in a race to build the most efficient emitters, or they lose business. The Chinese can sit on old tech and ride out Luxeon III based technology because they are selling at a cost per lumen perspective and they can post specs with fudged numbers few people can read. The mere fact I've pointed out so many times that a Bridgelux is not only cheaper but is actually brighter than the more expensive 10watt Ebay emitter proves this out.
As long as I'm having to explain half a dozen times a week in this forum and reefing forums to somebody that a $12 10-watt SEMI based Chinese LED with a rated range of 400-800 lumens bought on Ebay *is not* a better deal than a $8.50 800 lumen Bridgelux, then indeed the Asian
semi-conductor industry is going to win. Mostly because American consumers are too retarded to make intelligent choices based on junior high school science. Game over - inability to penetrate skull.
This has nothing to do with bigotry or flag waving, but the basic ability for educated consumers to read simple specifications. If LED #1 is more efficient, brighter, costs less and is posting reliable specs from Western company than LED #2, LED # 2 is not a better deal because it's posted on Ebay.
I'm not saying the Chinese emitters are a good buy. But I think your point on 10W LEDs is flawed. Anyone buying a 10W Chinese LED on eBay for US$12 is indeed an idiot because it doesn't matter what the actual specs on the LED are. 10W LEDs sell for under US$5 in single quantity. 20W LEDs sell for under US$9 again in single quantity. (I'm including shipping in both prices.) Even if you don't trust the cheapest ones, it doesn't make any sense to spend US$12 on a 10W Chinese white LED.
Also where is this US$8.50 Bridgelux come from? Something like Newark or something? If so, remember this is likely only really relevant for those in the US and a lot of people do live outside the US. The trouble with Bridgelux is they're difficult to reliably find on places like DealExtreme, eBay, Aliexpress which ship from HK/China. Finding them on these sites is important for some because if you're only buying one or two, shipping kills the deal outside the US (and possibly parts of Europe). It doesn't matter if the LED is US$8.50 if you pay double that when you take in to account shipping. (If you're buying other things from the same site and can combine shipping, great, but if you're just a hobbyist doing a one time thing you may not be.)
Also realisticly eBay and similar small level sales must be a tiny portion of the market for LED manufacturers even cheap Chinese ones. If they're hoping to make it big by relying on selling to small scale consumers, they've set themselves up for failure. But I'm pretty sure Chinese manufacturers are competing for the wider wholesale market such as those who use their LEDs in products, like the OP. Perhaps I overestimate that market, but I'm pretty sure when someone designs a product to be product in quantity, they don't just rely on lumen specs on eBay and particularly for cheap Chinese LEDs. They can probably get more reliable specs out of the manufacturer but I'm guessing most designers will evaluate products from manufacturers before deciding what to use. Yes the manufacturers can use a variety of methods outlined like sending good samples which the production quantities don't come close to matching to try and fool such testing. And later sprinkling good with bad to make it difficult to catch even in production.
In other words, I find it difficult to believe the Chinese manufacturers aren't competing on a dollars per lumen basis. They must be, because the only way they can compete is on cost as is always the case with no name Chinese products, and cost is meaningless in the abstract (I think we can all agree a
single Nichia 5 mm LED isn't going to win for home lighting against a Cree XM-L even though the Nichia is obviously cheaper.) As people have said, no one is going to buy them for consistency, or reliability, longivity, or colour performance and tint, and definitely not efficiency. They buy them for cost. And even if some of those who source them are rely so dumb as to rely on the Chinese specs without testing and these specs are wildly inflated, ultimately in a competitive market place these manufacturers are going to die. Their products won't be able to compete because when they try to sell them to businesses, government or consumers in the developed world they can't e.g. advertise wildly inflated specs because their LED manufacturer lied to them on the output. And even in the developing world, people tend to know not to trust the specs and while things can be confusing, it doesn't mean the company which tells the biggest lies wins so having an okay product usually matters. So those using name brand LEDs will be able to sell a cheaper product or make more profit if their name brand LEDs were cheaper per lumen. (Remember they can potentially choose a cheaper lower power LED from the name brand, and also bullshit about the specs of their product with the name brand LED.)
Of course one of the ways many of the Chinese manufacturers do this is by poor overall products i.e. as I've said means poor consistency etc clearly undesirable for any one using their products. Another way is by not caring if they violate patents while copying. Which is somewhat undesirable for a business. Although some the people in charge may not personally care about such practices, they have to consider the small risk to them for using products which violate patents. From an ordinary consumer POV, some would care, some don't. (I don't want to get in to the ethics, simply pointing out that not everyone cares.)
This doesn't mean the Chinese LEDs on eBay are the most effective on a price/lumen for consumers. They may be, they may not be, but not by enough to be worth it. You can get Cree XM-L for under US$9 including shipping from HK/China which beat the 10W and must come close if not beating the 20W. (The 20Ws often seem to be advertised as 1000-1100 lumens and based on the assumption this is likely inflated by at least 20% I'm guessing it's about 900 lumens or less so likely loses to a XM-L.) All run at close to max power of course. And even if the 20W LEDs beats a XM-L, the lower efficiency and all the other issues makes it's a questionable proposition, particularly since you'll probably be spending something on the heatsinking and PSU+driver so it's only part of the equation. And theoretically you have to spend more on the heatsinking. (I say theoretically because of course people may overestimate the heatsinking meaning they end up spending the same. Or they may underestimate and end up killing their Chinese LED.)
When it comes to coloured LEDs these are more tricky since name brand ones are harder to source from places like DX, eBay, AliExpress. Again if you live in the US and parts of Europe you may be able to source them from local manufacturers without being killed by shipping and possibly price for small quantities. Ditto if you're buying say 10-20 (depending on price range of LED) or a regular customer with some supplier. Although even then I don't know if it's always so clear. For example, you can get 20 red '3W' for about US$23-26 all up. The price for 11 (chosen because of price break) Red XP-E from Cutter is AU$29.59 (AU is close to par with US at the moment) without shipping (or taxes if you're Aussie). For me shipping adds another AU$9.00. I know the 3W Chinese red LEDs are unsurprisingly worse then Cree XP-E's
https://picasaweb.google.com/100774...AnalysisOfLEDCombinations#5604432572847116770 at 700mA and surely they're worse at 350mA too (athough it wouldn't surprise me if not by so much) but are the Cree's really worth it? Obviously they still have an reliability and longevity advantage. But tint/colour is obviously less a concern. And efficiency and heatsinking requirements would be better for the Crees but may or may not be a big concern. In other words, I wouldn't necessarily everyone choosing the Chinese ones are making a mistake.
P.S. I'm not saying there aren't a lot of dumb buyers on eBay etc. I'm the kind of person who sometimes bids on those auctions which Chinese/HK sellers run where the price can be a crapshot, and I see how common it is the winner pays significantly more then a buy it now auction for the same product from the same or different seller.
