I do find some led phosphors on Taobao, with a little higher price, still inexpensive. Maybe i should use those phosphors instead?
GPT tells me that fluorescent dye is organic moleculars, while led phosphors are rare earth crystals.
What did you think of the beam afterward? I see some scratch marks, so I’d guess that the beam is a bit more diffused, but probably didn’t lose too much brightness.
I’ve once done something much worse, soaking a reflector in laundry detergent overnight hoping to dissolve the fingerprints. Instead it dissolved the entire reflective coating…
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It stayed at the dedomed overall brightness, but the hotspot is noticeably dimmer, and the spill much brighter. I kind of like it, if it were just maybe 15% brighter hotspot. That’s kinda why I’m going to try the Invisible Glass cleaner on it…(I tell you what, that stuff won’t get iut scratches, but it is the CLEAREST my windshield (and flashlight lens) has been in a while. The reason you can notice the scratches is because I cleaned the lens with this stuff, lol…
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Could you share the link? I’m very interested. These dedicated LED phosphors should fare much better than dyes.
Not an expert on phosphors but what GPT said sounds about right. The phosphor in LEDs does appear crystalline once zoomed in. It’s quite similar to daylight-white glow powder. Incidentally, I’ve tried to make a green LED by de-phosphoring a 519A and re-doming it with UV resin with green glow powder mixed in. The glow powder phosphor did just fine, though the power handling is worse than the stock phosphor, saturating (turning opaque and letting through blue) at less than 1A.
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I think it’s not necessarily a uniform distribution more so as an aggregately uniform distribution…remember the projected images we did a while back, showing a grainy phosphor spatter?
Whenever I’ve needed to clean reflectors, like after grinding the opening larger etc, I will flush it with 99% ISO, rinse in warm water, then flush the tap water out with a little distilled water so there are no water spots.
Then blow dry it with air.
Always works good.
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This makes sense, the micro-scratches on the reflector are shifting the mode of reflection farther from specular (mirror) and closer to diffuse (white paper). Hence dimmer hotspot and brighter spill.
I must say I haven’t tried the glass cleaner you mentioned, the results sound very impressive. I’ve had luck cleaning glass with just liquid handsoap and water.
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It’s “cheap”…$5 bottle at Vertical Structural Divider Mart.
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Sorry, I’m not seeing the distinction between uniform distribution and “aggregately uniform”, or the connection to the projected images of the phosphor.
So with an applied phosphor, it doesn’t necessarily need to be a perfectly uniform layer. Splotchiness might be OK, as long as the correct amount of phosphor is activating to produce the desired CCT/tint
Ahh, distilled water is crucial! I’ve cleaned reflectors with tap water, and all sorts of solutes appeared after drying.
For cleaning dust from reflectors, my current method is clear silicone “nanotape”, which is a homogeneous solid sticky substance that does not leave any residue on the reflector surface. I cut a bit to mount on a toothpick and gently touch the dust spot to lift it right off, and the reflector becomes good as new. This works great if there are only few dust spots; if the whole thing is covered then I would have to give distilled water a try.
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Does it work similar to that NASA sludge scooper?
I’m not aware of this device; could you link a description/article on it?
I think it depends on the application. If your LED is hidden behind a heavily beaded TIR, chances are you can get away with crap like this:
But if you’re going with a reflector- or clear TIR thrower, then the phosphor surface should be as uniform as possible, to avoid the infamous egg-yolk hotspot that plagued early 5000K SFT25R’s.
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Maybe it wasn’t nasa…my search algorithm isn’t showing me anything…It’s a thing that could pick up an irregularly amorphous blob and transpose it to another surface, provide the pickup surface was non-absorbant/non porous
I’m still unsure what the actual device is, but I guess the silicone tape intends to grab the dust and never release it again. Strangely enough, it is almost completely non-sticky to the reflector’s surface.
I also use the same material to clean glass lenses and TIRs; the tape sticks to these materials much more than it does to a reflector, and if not careful, bits of the tape can break off.
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Bet ya can 
What is this devilry? …Is it this> Amazon.com ??
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I think that’s the same substance, though I get mine much cheaper on Aliexpress.
This stuff is crazy useful in general, aside from cleaning optics and LED surfaces. For example, it’s heat-resistant enough that I use it to hold tiny SMD components in place to solder them without a circuit board. That’s how I did the tiny SMD work in the analog voltage-indicating switch, despite crappy soldering skills. One side of the tape is stuck to the table, while the top side holds the components.
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It says the phosphors is composed of (Sr,Ca)AlSiN3:Eu. I kind of feeling it is the right one.
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So after the invisible glass, (I just spritzed a bunch into the reflector and sloshed it around before going at it with a (TABOO, COVER YOUR EYES!) paper towel. Here’s how it looks now…Might just be a +
, but it seems to be throwing better by a bit?
It seems to have taken the isoprop residue off, but couldn’t do anything about the microscratching. I might go another round with a microfiber or a polishing cloth just to FAFO…