Thatās what I donāt understand. If it is more blue and brighter the less phosphor, why are blue xml dimmer? I donāt think there is any way to āredomeā an led after stripping the phosphor is there?
"For example, the efficiency of a typical...yellow phosphor based white LED ranges from 3 to 5 times the efficiency of the original blue LED because of the greater luminous efficacy of yellow compared to blue light."
Basically, human eyes are much more sensitive to white (or yellow) light which is the cause of all this.
http://en.wikipedia.org/wiki/Luminosity_function
The blue light produced is at 450 nm while the white light (after going through the phosphor) is around 575-600. So if you look at the graph, the human eye is very sensitive to white light, but not the blue light.
Excellent resource. Now if you could do one on the meaning of āXM-Lā vs āXP-Gā etc. It would be neat to know more behind the naming and designation of each.
What do you mean? The number of bond wires, size, efficiency, etc? Maybe if I get a chance I'll do that but this one was prompted by a few people PMing me in the past about tint, along with Nitro's question about where to get a neutral LED.
What surprises me is I was able to do 90% of this with out having to look anything up, I guess that's what happens when I spend so much time here.
Iām beginning to worry about how much I soak up on something I take an interest in, six months ago, I didnāt know what an xm-l wasā¦.know Iām growing bored of themā¦not bored as in not using them, just want to play with other things, Iām going backwards though, starting playing with xp-gās etc. Bothering about modes and tint more than total output.
Sometimes a q5 in a suitable host with a good 1.4a driver is more usefull than an over driven xm-l lumen monster.
I think Iām in the same boat as you. I have drawers full of lumens and sheer output isnāt a real big deal to me any more. Iām now more drawn to different tints and their visual relation with different beam profiles. If I see a flashlight with a choice of an XP-G 4C - 450Lm or an XM-L U2 - 800Lm, I will probably go with the XP-G 4C.
The bad thing is, I should get a p60 host, build many pills, then its half scientific. Thatās not going to happen though, I just donāt like p60ās so common sense is out the windowā¦
Not quite. CW XML typical CRI is 65. Typical CRI for CW XPE, XPG, XRE, Rebel, and most other current gen 3.45mm square emitters is between 70 and 75. Typical CRI for NW and WW emitters depends a lot on the specific model of emitter. For NW, it ranges from 70 to 80 depending on the type of emitter (not including "high CRI" emitters), and for WW, it ranges from 75-85 (also not including "high CRI" emitters).
Nice thread along with your other comparison thread.
Question - XM-L led's include a high CRI bin. I dont see this or anything about it..Sure, its for sale somewhere. I think its an S2 bin although i may be wrong in regards to the bin
Yes, to find that type of LED you need the model number. This is listed in the datasheet. Then simply take the model number and google it. (In this case: