Gryloc
Enlightened
Seeing how high CRI LEDs are becoming more popular at the CPF, and knowing how picky some of us can be with choosing the tints of our white LEDs, I am surprised that no-one else posted any threads about this. Here is the link to the products page:
http://www.philipslumileds.com/products/luxeon-rebel-white/
In order to see the press release, just navigate to the home page and check out the "What's New".
So, here we have the use of what appears to be special phosphors in order to obtain a more exact tint that falls on or near the black body line. I read through some documents on Lumiled's website, as well as to some posts on the CPF, and I learned that previously, only the warm white Rebels used Lumiled's Lumiramic phosphor technology. If you look at some of the pictures of these newer Rebels in the datasheets, the phosphors look very unique. Since these newer Rebels are CCT specific, then does that mean that all of them use the new Lumiramic phosphor technology? If so, I think that only the LXML-PW51 emitter either does not, as you will find it has slightly different "Relative light output vs. thermal pad temperature" curve. I assume this is because the use of different phosphors than the rest (it has slightly worse performance like the old TFFC Rebels). Regardless, the newer Rebels perform better than the older TFFC Rebels when it comes to light output vs temperature, and forward voltage versus forward current.
I wonder if the die image will have such strong artifacts as the original TFFC dies (due to the apparent grid of vias). If the new phosphor is thicker and/or diffuses the light a bit more, maybe those dark spots from the vias, and the resultant artifacts will dissapear!
Even though these emitters are not yet available, this is great news for those in the lighting industry (especially residential). This is also those who desire the color temperature (and as a result, a perfect tint) without sacrificing CRI as much. With these, hopefully we will not get the usual ugly variations that we have learned to cope with (such as the ugly urine-green, blue, and pink tints).
These newer Rebels have the same super low forward voltages as the once new Rebel ES. For example, the typical Vf at 350mA is only 3.0V. This is wonderful considering some XR-E and K2 emitters have relatively high Vfs (some similar to the old Luxeon K2s: eek).
BTW, a bit off topic: I was lucky enough to purchase a bunch of 0200 TFFC K2s a while back, and these actually have the same Vf range as these new Rebels (in my careful testing during burn-in). I feel so lucky to have a average Vf of 3.08V @ 350mA, 3.23V @ 700mA, 3.33V @ 1A, 3.45V at 1.5A and even only 3.54V @ 2A. It makes electrical design a bit easier at times!
So, even though many have forgotten about Lumileds, it is still interesting how they have improved their Rebel LED line (both for whites and colors -namely amber).
Cheers,
-Tony
http://www.philipslumileds.com/products/luxeon-rebel-white/
In order to see the press release, just navigate to the home page and check out the "What's New".
So, here we have the use of what appears to be special phosphors in order to obtain a more exact tint that falls on or near the black body line. I read through some documents on Lumiled's website, as well as to some posts on the CPF, and I learned that previously, only the warm white Rebels used Lumiled's Lumiramic phosphor technology. If you look at some of the pictures of these newer Rebels in the datasheets, the phosphors look very unique. Since these newer Rebels are CCT specific, then does that mean that all of them use the new Lumiramic phosphor technology? If so, I think that only the LXML-PW51 emitter either does not, as you will find it has slightly different "Relative light output vs. thermal pad temperature" curve. I assume this is because the use of different phosphors than the rest (it has slightly worse performance like the old TFFC Rebels). Regardless, the newer Rebels perform better than the older TFFC Rebels when it comes to light output vs temperature, and forward voltage versus forward current.
I wonder if the die image will have such strong artifacts as the original TFFC dies (due to the apparent grid of vias). If the new phosphor is thicker and/or diffuses the light a bit more, maybe those dark spots from the vias, and the resultant artifacts will dissapear!
Even though these emitters are not yet available, this is great news for those in the lighting industry (especially residential). This is also those who desire the color temperature (and as a result, a perfect tint) without sacrificing CRI as much. With these, hopefully we will not get the usual ugly variations that we have learned to cope with (such as the ugly urine-green, blue, and pink tints).
These newer Rebels have the same super low forward voltages as the once new Rebel ES. For example, the typical Vf at 350mA is only 3.0V. This is wonderful considering some XR-E and K2 emitters have relatively high Vfs (some similar to the old Luxeon K2s: eek).
BTW, a bit off topic: I was lucky enough to purchase a bunch of 0200 TFFC K2s a while back, and these actually have the same Vf range as these new Rebels (in my careful testing during burn-in). I feel so lucky to have a average Vf of 3.08V @ 350mA, 3.23V @ 700mA, 3.33V @ 1A, 3.45V at 1.5A and even only 3.54V @ 2A. It makes electrical design a bit easier at times!
So, even though many have forgotten about Lumileds, it is still interesting how they have improved their Rebel LED line (both for whites and colors -namely amber).
Cheers,
-Tony
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