the emitter with the highest surface brightness
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You sure about that?
Tatjanamagic
Enlightened
Saabluster you are God of aspherical flashlights.
Please tell us your opinion which emitter has highest surface brightness.
srfreddy
Enlightened
I think the SST-50 overdriven to 9 amps would certainly have higher surface brightness....
Walterk
Enlightened
He used the Cree XRE for the Deft for a reason. Now the Cree XML is quite 'hot' and promising. See: Why a good thermal path really matters
And:
Die luminance, emittance and advanced die heatsinking
Formula for calculating throw using aspheric lens
archer6817j
Enlightened
Mash.m, what kind of aspheric are you using in those photos?
Thank you for the commendation but I am uncomfortable being called the god of anything much less the God of something. That would be reserved for the Almighty.
I do believe we have a new winner but before I post my results I want to be absolutely sure of what I am speaking. I am in the process of building myself a high precision integrating sphere. I will do some tests in that first and report back my findings.
Tatjanamagic
Enlightened
U can not be the God but you are the King of aspherical flashlights that nobody can deny...
I am looking forward for your report.
Plenty of people here think that there is no future for aspherical flashlights... I am glad that there are people constantly trying to improve their product.
Ideal aspherical flashlight for me would be with adjustable focus, acceptable size and with nice round beam throwing blinding clearly up to 400 meters, and of course gun mountable.
With new emitters coming that dream could became achievable.
I am looking forward for your report.
Plenty of people here think that there is no future for aspherical flashlights... I am glad that there are people constantly trying to improve their product.
Ideal aspherical flashlight for me would be with adjustable focus, acceptable size and with nice round beam throwing blinding clearly up to 400 meters, and of course gun mountable.
With new emitters coming that dream could became achievable.
Other than the round throw beam all these are possible now. It is of course possible to have the round beam but not in the highest throw situation. For that we are beholden to the shape of the die. I've had a unique adjustable focus mechanism for aspherics for almost two years now but not the time or money to implement it.
Tatjanamagic
Enlightened
I have talked With Deerelight costumer support and they have told me that [FONT="] XR-E R2 is still the king of throw in the asphrical lenses...
Saabluster do U have something new on this theme?
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Saabluster do U have something new on this theme?
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gcbryan
Flashlight Enthusiast
It's because it still has the highest surface brightness. All the newer emitter just get getting larger rather than brighter (lumen rather than lux goes up).
znomit
Enlightened
XR package throws more light out the front too, making it better for aspherics.
Exactly, a narrower viewing angle is better when working with Aspherics.
I wonder how well the XP-G would throw/perform if it came out in the XR package, instead of the XP package. AFAIK, it would be easier to heatsink/have more effective heat transfer from the die to heat sink... And the narrower viewing angle would be great for the variety of optics out there for the XR-E, as opposed to the XP-E.
znomit
Enlightened
ps I always thought that the XR-C had the highest surface brightness.
I do. znomit was very close. It is the XP-C. One has to be clear what is being said when talking about which one has the highest surface brightness as it depends on what the ground rules are. Are we talking about at a matched specific drive level, the max suggested drive levels for each respective LED, or the absolute potential which comes with overdriving?
I tend toward the absolute limits when making a determination because if you say LED A has more than LED B when they are both @350mA but LED B can be driven far far harder and be more intense than LED A at its limit then the prior declaration is up for dispute. The best LED I have tested to date is the Q4 binned XP-C. The XP-E HEW may do well but I haven't had a chance to test it yet. I was wanting to get my hands on the R5 binned XP-E HEW before I made my proclamation but you guys just can't seem to wait around here.
I doubt the HEW will be able to do it because of what I have heard about the phosphor deposition technique. I have some R4s in hand but have not tested them yet. So for now I feel fairly confident in saying the XP-C takes the cake.MikeAusC
Enlightened
Do you mean Surface Brightness - or Effective Surface Brightness ?
Do you plan on de-doming the LED ? If so, then you can compare LEDs based on the brightness of the phosphor.
If no de-doming, then you need to compare them based on phosphor brightness AND how widely the lens spreads the phosphor image - if the beam angle is 40% wider, the light from each particle of phosphor will be spread over twice the area, reducing effective brightness.
Do you plan on de-doming the LED ? If so, then you can compare LEDs based on the brightness of the phosphor.
If no de-doming, then you need to compare them based on phosphor brightness AND how widely the lens spreads the phosphor image - if the beam angle is 40% wider, the light from each particle of phosphor will be spread over twice the area, reducing effective brightness.
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Perhaps not for flashlight discussion, but I have some info. on fresnels and aspherics on 2 recent applications using them.
Adjustable focus light units have ( on-camera video lights ) recently brought to market, as 2 newer models have been shown to be very popular because of that feature. One model uses 2 lenses (aspherics) and the other model uses a single fresnel of arounf 3mm in thickness in front of the led. Both models have a single led in them. Perhaps a fresnel can definitely be used for the focusable feature. I am sure it has been done on a flashlight before as fresnels are over a century old, but having one on a XM-L should be awesome. In the fresnel model light http://www.litepanels.com/sola_eng.html that is achieved by rotating the front bezel to distance the fresnel from the led similar to a camera lens as it is being focused closer. It is a matter of male/female circular threads. Same principle for the aspheric unit http://www.dedolight.com/www/dedoli...000004OO&id=DL_Ledzilla&mode=search§ion=0 That varies the angle from 4 to 56 degrees.
If fresnels prove to be effective, then perhaps there is a market for a focusable fresnel flashlight, I myself was looking for the holy grail in the design of my video light using fresnels, but sourcing the proper size was almost impossible and the added mechanical design of varying the small distance change from the led to fresnel surface was too much of a challenge. Please keep us up to date of your design , as I am sure that would surely be a welcome feature.
