Gryloc
Enlightened
:help:
(Oops, messed up when posting this thread - sent to wrong category. Hope this works)
Hello. I have always come to the Candlepower Forums for tips and info, but I never registered. Now here I am. Anyways. I was wondering about the shape of the die of a Luxeon Star. I held up an assortment of the Luxeon Stars that have acquired over time, and I compared the sizes of the LED die. The 1W white die is about 1mm wide (approx. 1mm^2), the 3W white die is about 1.5mm wide (approx. 2.25mm^2), and the 5W white die is about 3mm wide (approx. 9mm^2). So, why isn't the brightness proportional to the LED die size? This really bugs me!
Ok, the 3W white is an oversized 1W. It has an area that is 2.25X bigger, so why isn't the brightness at least 2.25X brighter? Throughout this post, I will mostly compare the brightness (in lumens) from what was given on the Lumileds datasheets. The old 1W used to put out 25lm at 350mA, and the cheap 3W (S-binned) put out about 60lm at 700mA. This is pretty close to 2.25X brighter. Now, you can get a decent 45lm 1W Luxeon Star, so you should be able to get a 3W that puts out 100lm just as easily, right? I wish. This is assuming that the 3W uses the same new technology (and efficiency - lm/W) as the latest 1W. Now they do have the U-binned 3W, but they are a bit difficult to get a hold of one. Why is this? Using my theory, the common T-binned 3W (typ. 80lm) still uses the same technology as the 35lm Q-binned 1W. This really isn't too bad; it really doesn't concern me.
What really grinds my gears (ha-ha) is the 5W Luxeon star. This older monster is said to have 4 1W dies together in a single LED. Now this is okay to believe, but when you really think about it, it really makes no sense. Why is the die(s) on the 5W so big? They compare to the size of a 3W die. I understand that a different technology is used in the making of 5W Luxeon Stars, but why is it so large like this? The quad 1W idea can work because 4 older 1W (Q-bin equivalent) at 30lm together makes 120lm. Using 4 1W die with the brightness each from 38lm to 40lm can yield a W-bin 5W (about 150 to 180+ lumens). I have one of these W-bin 5Ws and it is ok (not super bright). Why do they use 4 led die that are the size of the 3W? This gives you a beam, when using a good reflector, that is too big. The 5W are hard to make a good light that has a lot of throw to it. Imagine if they made a 5W with 4 actual 1W die. The surface of the 5W die(s) would measure about only 2mm by 2mm! This would give a nicer beam with better throw. The 3W red/orange has a die that is 2mm by 2mm. The throw is improved because of this, but it is red light that isn't as useful (except for spotting raccoons with).
Wow this is a long post. I have plenty of questions. Now, using my theory on the size of the die, the 5W, using "3W equivalent sized die", should put out at least 65 X 4 lumens (260lm)! This is an average 3W driven at only 700mA. Now I know that it isn't the same, but I am saying all of this assuming that Lumileds is using the same or similar technology, when it comes to lm/W and die size. I know the 5W is a series/parallel set up of LED die (350mA per die). Does this make sense? What if Lumileds did make a 4 X 3W Luxeon Star LED? The package would look the same, it would just run a about 7.8V @ 2A and put out about 320lm.
Also, using my theory with the die size, the 5W has a die that measures 3mm by 3mm (9mm^2). Why isn't the brightness 9X greater than a typical 1W? Why don't they attempt having a LED package with 9 X 1W LED die? This would yield approx 270lm to 405lm at (using the series/parallel setup) 12V at 1050mA.
So why doesn't Lumileds have their 5W with a smaller 2mm by 2mm die? Why don't they just use 4 3W die in the package? How about 9 1W die in a package to replace the 5W? These are crazy and dreamlike concepts, but I was just wondering why the die size was not proportional to the brightness in the whole line of Luxeon Star LEDs. I know that too many die for a higher power LED would mean higher cost, more heat generated, and a greater complexity of manufacturing, but I was just wondering and wishing. No one seemed to have talked about this before, and it has bugged me for sometime. What is with this? Please help me. Maybe others can learn from this, or ideas for a more powerful LED can be created.
Finally, why can't Lumileds use a large, single die that measures from 3mm to 4mm (or more) in size? This would perform well in the super high-end lighting or the automotive industry. I don't know about the chemistry an LED die, or of the process of making the LED die, so this may be impossible. If they cut the die into larger pieces, and mount them on a larger copper slug, would that be awesome? Can you imagine how much light can be produced? I know there would have to be multiple lead wires to connect the massive die to the anode. Also, a large amount of while-light-producing phosphor would have to be slathered on top. Imagine a die that is 6mm by 6mm that emits nearly 1600lm to replace an incandescent headlight bulb. I was just thinking.
This post, again, is way too long, but respond with whatever answers you might have or any comments. I would greatly appreciate any sort of feedback. Thanks!
(Oops, messed up when posting this thread - sent to wrong category. Hope this works)
Hello. I have always come to the Candlepower Forums for tips and info, but I never registered. Now here I am. Anyways. I was wondering about the shape of the die of a Luxeon Star. I held up an assortment of the Luxeon Stars that have acquired over time, and I compared the sizes of the LED die. The 1W white die is about 1mm wide (approx. 1mm^2), the 3W white die is about 1.5mm wide (approx. 2.25mm^2), and the 5W white die is about 3mm wide (approx. 9mm^2). So, why isn't the brightness proportional to the LED die size? This really bugs me!
Ok, the 3W white is an oversized 1W. It has an area that is 2.25X bigger, so why isn't the brightness at least 2.25X brighter? Throughout this post, I will mostly compare the brightness (in lumens) from what was given on the Lumileds datasheets. The old 1W used to put out 25lm at 350mA, and the cheap 3W (S-binned) put out about 60lm at 700mA. This is pretty close to 2.25X brighter. Now, you can get a decent 45lm 1W Luxeon Star, so you should be able to get a 3W that puts out 100lm just as easily, right? I wish. This is assuming that the 3W uses the same new technology (and efficiency - lm/W) as the latest 1W. Now they do have the U-binned 3W, but they are a bit difficult to get a hold of one. Why is this? Using my theory, the common T-binned 3W (typ. 80lm) still uses the same technology as the 35lm Q-binned 1W. This really isn't too bad; it really doesn't concern me.
What really grinds my gears (ha-ha) is the 5W Luxeon star. This older monster is said to have 4 1W dies together in a single LED. Now this is okay to believe, but when you really think about it, it really makes no sense. Why is the die(s) on the 5W so big? They compare to the size of a 3W die. I understand that a different technology is used in the making of 5W Luxeon Stars, but why is it so large like this? The quad 1W idea can work because 4 older 1W (Q-bin equivalent) at 30lm together makes 120lm. Using 4 1W die with the brightness each from 38lm to 40lm can yield a W-bin 5W (about 150 to 180+ lumens). I have one of these W-bin 5Ws and it is ok (not super bright). Why do they use 4 led die that are the size of the 3W? This gives you a beam, when using a good reflector, that is too big. The 5W are hard to make a good light that has a lot of throw to it. Imagine if they made a 5W with 4 actual 1W die. The surface of the 5W die(s) would measure about only 2mm by 2mm! This would give a nicer beam with better throw. The 3W red/orange has a die that is 2mm by 2mm. The throw is improved because of this, but it is red light that isn't as useful (except for spotting raccoons with).
Wow this is a long post. I have plenty of questions. Now, using my theory on the size of the die, the 5W, using "3W equivalent sized die", should put out at least 65 X 4 lumens (260lm)! This is an average 3W driven at only 700mA. Now I know that it isn't the same, but I am saying all of this assuming that Lumileds is using the same or similar technology, when it comes to lm/W and die size. I know the 5W is a series/parallel set up of LED die (350mA per die). Does this make sense? What if Lumileds did make a 4 X 3W Luxeon Star LED? The package would look the same, it would just run a about 7.8V @ 2A and put out about 320lm.
Also, using my theory with the die size, the 5W has a die that measures 3mm by 3mm (9mm^2). Why isn't the brightness 9X greater than a typical 1W? Why don't they attempt having a LED package with 9 X 1W LED die? This would yield approx 270lm to 405lm at (using the series/parallel setup) 12V at 1050mA.
So why doesn't Lumileds have their 5W with a smaller 2mm by 2mm die? Why don't they just use 4 3W die in the package? How about 9 1W die in a package to replace the 5W? These are crazy and dreamlike concepts, but I was just wondering why the die size was not proportional to the brightness in the whole line of Luxeon Star LEDs. I know that too many die for a higher power LED would mean higher cost, more heat generated, and a greater complexity of manufacturing, but I was just wondering and wishing. No one seemed to have talked about this before, and it has bugged me for sometime. What is with this? Please help me. Maybe others can learn from this, or ideas for a more powerful LED can be created.
Finally, why can't Lumileds use a large, single die that measures from 3mm to 4mm (or more) in size? This would perform well in the super high-end lighting or the automotive industry. I don't know about the chemistry an LED die, or of the process of making the LED die, so this may be impossible. If they cut the die into larger pieces, and mount them on a larger copper slug, would that be awesome? Can you imagine how much light can be produced? I know there would have to be multiple lead wires to connect the massive die to the anode. Also, a large amount of while-light-producing phosphor would have to be slathered on top. Imagine a die that is 6mm by 6mm that emits nearly 1600lm to replace an incandescent headlight bulb. I was just thinking.
This post, again, is way too long, but respond with whatever answers you might have or any comments. I would greatly appreciate any sort of feedback. Thanks!