This thread is about data points regarding the new generation of LuxeonIII LEDs with the different placing of the LED die resulting in a different photon management.
As I don't know anything about it, I'll re-post Don's comments of some other threads in this one place here so that we have a good starting point for further discussion.
bernie
As I don't know anything about it, I'll re-post Don's comments of some other threads in this one place here so that we have a good starting point for further discussion.
bernie
Don said:These PD's have the "new style" Luxeon LED's and I have recently had it come to light that the "new style" does indeed have a new image location relative to the package and consequently the beam is different than that of the previous LuxIII.
Fortunately for me and my customers, the only lights I have built with "new style" have been the HD's and now this group of PD's. The good news is that the beam is OK in terms of white wall. It is actually better if you are like me and prefer more light in the corona and more of a divergent flood beam with the spot. It is not good news if you want max lux and throw from the light!
I saw a post a few weeks back about the revised LED with the new round heat sink and apparent "lowered" die but there was little follow up comment and it was also shown, as I recall, that the new style was working fine with existing optics and lights. I will post my preliminary observations in a new thread here in this forum later tonight if I can get to it. In the mean time, I have discovered that it would appear that the reflector's curve needs to be dropped down about .015" to .020" to return to focal allignment. This is a PITA as the reflector's geometry as well as the heads geometry is not open to such realignment without some modification! In the case of the PD, I need to shave off the rear end of the reflector as well as shave off a shoulder on the reflector that is designed to reference off a mating shoulder within the PD head.
As is, these lights here will give you a brighter corona and larger spot but with less definition in spot and less intensity in the spot. Ironically, this is more in keeping with recent reflectors I have been designing but none the less, this comes as a rude surprise that was not bargained for!!
Don again said:The flux or luminous output of these PD's will be exactly what it should be with these U bin LED's. However, as assembled, the beam from these will favor a softer blend in hot spot to brighter corona as compared to if they were assembled using what one would assume to be the "standard" Luxeon. The lux of these lights takes a hit as a result. I have tested a couple set up and one was in a very controlled test where everything tested was the same with the only exception being a modification to the same exact reflector and then a re assembly. In the case of the 20 mm reflector, you can expect about a 50% increase in lux if the reflector were put in sharper focal allignment with the LED. On the other side, consider this about a 35% reduction in lux from what it could be. I.E. 1000 lux in current flood/blended state and 1500 lux in sharper spot with reduced corona intensity. Since this batch of PD's is the only set of PD lights I have used the new style Luxeons in, I am willing to offer these lights either as is (good flood beam and better than normal for corona intensity) or I will take them apart and modify the reflector to match this new geometry.
This is ultimately going to get pretty confusing and I know that I have no desire to spend time cutting perflectly good reflectors and especially when I prefer the beam that results with this new "de focus". I don't consider the PD as a light designed for throw and I think this new distribution of light is actually an improvement over the properly alligned reflector with previous "standard" Luxeon. I have been playing with a pair of PD's with the only difference being the reflector adjustment and the difference is visible and the foreground and mid distances are improved with the missalignment but the distance is reached much better with the adjustment made.
This alert is only in regards to these lights here and all of the previously build PD's, inclusing those with U bin LED's were of the "standard" Luxeon and not this new joker! Those of you who have already been shipped one of these have the option of a reflector modification if you choose and any of these to be purchased come with the option. Beyond these, I have not decided what I am going to do but since the TY0J and TW0J LED's I am building with are of the "standard", the point is moot.
Don can't stop said:However, after looking at the lux measures of this powerful UX1J behind the 27 mm reflector, I knew something was goofy! I had noticed that the spot was rather smooth and not sharp but didn't give it any thought. Well, the LuxIII in this CPF standard is of the new packaging which has been briefly mentioned but not really explored to my knowledge; or at least really delved into here on CPF. To date, I have only used the new style LED's, to my knowledge, in my HD45 and very recently, some U bins in some PD's of color. I am now aware of the fact that these LED's do in fact have an image location different than their predecessors and focal allignment is not the same!!! I have attributed the less than stellar lux measures of the HD45 to the orange peel of the reflector when it now seems that a possibly stronger influence is the fact that the reflector is in effect forward of the focal point by probably .015" to .020" at a guess. Ironically, I have been trying to design and effect optics which cause the beem to diverge more and get more light in the corona and it seems that Lumiled's, in their infinite wisdom has implimented a push in the same direction without any alert to us lowly customers! The good news to flood lovers and white wall hunters is that at least in the case of the lights I have been making, the beam will not disappoint nor does it look bad. However, if you are in fact looking for high lux measurements and long throw, these new LED's will require modifications to optics designed for the previous packaging and/ or placement changes within their hosts! WTF!!!
I have been sitting on this post while I did a quick build and light test. I put one of the new version (we need a friggin name for these damn things!) Luxeon's (UX1K) in a Light Engine with DB917 driver. I put the LE in an Aleph 2 head with stock reflector and no window and put it in the integrating sphere as well as took a lux measurement with it. 80 lumens and a lux of 1030. I then took this same reflector and faced .015 off the rear of the reflector and put it back with the same LE and again took flux and lux measures. 80 lumens once again but the lux jumped up to 1525. There was essentially an increase of 50% in the lux measure! There is no loss of photons but the deployment is certainly effected!
A quick and late query to the Future Reps I have been in contact with resulted in a comment of essentially, news to them! I suspect that there is going to be mixed inventory coming down the pike in production units and some manufacturers may catch wind of something not quite right or the same from customers who may notice something "off" about the lights. :shrug: In addition to the fun lottery, Lumileds it would seem has added blind siding of the customers as an additional bonus and part of the game.
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