I suspect a spacer for consistency, so that everybody participating held the light the same distance from their eye for equal beam intensity.
thanks for your post and for sharing info
I wonder if going outside, and with eyes closed letting the sun shine on my face and eyelids, would produce similar benefits as an LED…
I wonder how we can measure and compare Red light sources, so we know their relative power levels.
I dont know enough yet if One Sofirn AAA light with Red LED can have comparable benefits as one of those multi LED arrays… when the goal is specifically to illuminate a small target… even just One Eye at a time…
more info needed regarding exposure time also, relative to the number of LEDs… and comparing that to using Sunlight as a source of red… (IF that is even a viable option)
I noticed this too, Declining eyesight improved by looking at deep red light -- ScienceDaily
so naturally BLF was the first place I looked.
There is a previous BLF topic here : WTB Deep Red LED Flashlight or build one for me - #33 by hank
Who here is at UCL ?
It’s not entirely comparable since it is a food additive instead of a medical treatment. Regardless, the initial approval involved, was as far as I know, a normal volume of research. However, due to problems in the initial research submittals used to grant it approval, which seem like deliberate corner cutting by the manufacturer, it went through years of followup review. I wouldn’t be surprised if, as a result, it’s one of the best studied food additives there is.
Are you suggesting that FDA approvals should take longer than the 2+ decades that aspartame ultimately went through between initial application and the end of all the challenges?
I recently ordered a fairly priced custom 2x red + 2x deep red quad star @ HotRed Official Store, you may want to check this “deep red” search there.
thank you very much for helping to educate me about real world options to translate theory into practical action
maybe this LED I found thanks to your search, could be a basis for conversation and comparison
what I notice that seems useful (Im really new at LED shopping), is the 3535 footprint, the 16mm mcpcb, and the 3 volt category… since that fits with my limited knowledge of the traits of the sw45k I put into a Nitecore EX11.2.
Im considering that EX11.2 as a potential host for the Red Led… a simple platform that Im familiar with, and can mod easily with preflowed LED board swap…
another light I am considering making Red capable is the AAA Coopper Tool for which I would do my own reflowing (which I learned how to do recently, and have been enjoying very much)
Hey! The deep red emitters link you grabbed is a 100 piece sale. O:)
HotRed sells a wide range of super cheap 0K quality copper MCPCBs, of which most of them are DTP (the 20mm 3535 XPE and the 20mm XML/5050 look non-DTP).
Here is their sale link for a single XP-E photo deep red 660nm: https://www.aliexpress.com/item/32699141532.html (10 pcs pack here).
Since you can select bare led or led mounted on a cheap aluminum star, I am pretty sure they will gladly reflow your deep red emitter on a ∅16mm copper star (those are DTP, I have ;-) them at home) if you send them a message after purchasing the emitter(s) and board(s).
thanks, I did not need 100 of them… LOL
Estimated Delivery on 09/24
I will think it over
If you’re buying it presoldered on an MCPCB, the footprint does not matter directly. If you’re going to reflow it yourself, then you need to make sure that in addition to the size of the footprint, the solder pads having similar dimensions and polarity.
The most popular form factor matches the Cree XP series - 3535 with an electrically neutral thermal solder pad in the middle. In addition to the Cree XP-series, the Cree XHP35, the Nichia 219 series, the Samsung LH351 series, and the Luminus SST-20’s use that footprint.
Mountain Electronics has a 20mm MCPCB with a 660nm XP-E on it. They list a 16mm version as out-of-stock, unfortunately.
Cutter (in Australia) has the XP-E in 660nm photo red and 730nm far red, and can mount it on several different sizes of MCPCB’s. If I remember right, they do ship to the US, but I don’t know the cost.
I’m sure they can be had from Digikey or Mouser, too, but I don’t have time to dig up part numbers to search at the moment.
I have both Emisar D18 and Emisar D4V2 with deep red SST-20-DR emitters. They are fun to use, and quite bright! 
For a small fee, Hank from intl-outdoor can build a flashlight for you with custom emitters. I emailed him and asked for SST-20-DR-B120-V660.
Note that the human eye is significantly less sensitive to deep red light, so if you get a flashlight with only 1 deep red LED it won’t be very bright.
Selecting same shipping option for both items means shipping gets combined.
Now, that's some real good news! What driver did Hank use for the Emisar D4V2? I can't imagine that SST-20-DR will like high currents with FET. Did he use the 5A driver from KR4 or is the maximum current limited by software (Andúril)?
There is nothing different about it, it uses the standard D4V2 driver.
I don’t think Hank used limited FET firmware (typically used for Nichia 219) in mine. I assume he would have told me if he did, so that I would know to use the limited FET firmware when I flash a new version.
SST-20-DR is rated up to 3A, which is the same as SST-20 4000K. It seems to heat up less than my D4V2 with SST-20 4000K, so I assume it is not pulling too much current. Maybe it is more efficient? It does have a low Vf, so I wonder how much current it is actually pulling, and if it could be an issue.
https://download.luminus.com/datasheets/PDS-003040-Rev-04-SST-20-DR.pdf
While I don't know the fine details of what you are discussing concerning that D4V2, I will just say that driving deep red emitters in parallel with an unregulated driver is just bollocks. Even a linear driver is inadequate, because the large voltage difference between input and emitters Vf needs to be dissipated at the regulators, being very inefficient and causing massive heat dissipation.
The right answer is a buck driver, or a boost driver with emitters in series (or boost-buck if 2S2P). Maybe its time to develop some :???: new driver, because every time I look for buck drivers in the chinese market it either makes me want to cry or kick someone else's arse let's say I just don't like what I see. O:)
I’ve seen the same press coverage regarding this. I’ve got eye issues and I support myself and my family doing graphic design and it’s a great worry as I get older. I want to look into this to support my eye function going forward.
There’s not much info about how to make a 670nm red light source, though you can buy them for upwards of 100 EUR. I’m certainly no technical whiz, but any tips gratefully received.
Thanks!
Here’s where you can order a 670 nm LEDs, from Germany.
https://www.ebay.es/itm/3W-5W-670nm-POWER-LED-on-HEATSINK-Kühlkörper-Emitter-5mm/282856779018?var=582259449628
I think making a homemade flashlight maybe the simplest and most practical option if you are going to do this for eye treatment.
Link edited and decrapified.
It's hard to extract any conclusions concerning how good such emitter is without any further information, i.e. manufacturer & model, datasheet and/or some real-world test(s).
The format of the emitter looks unenticing for flashlight usage.
Hi,
We are already taking here about 10W LEDs like SST-20-DR. Does anyone know what power is actually needed? Maybe couple 5mm LEDs is enough?
Red and IR LEDs are already used in all kinds of therapy. See sample description here.
I have seen a device for that myself. Have a fried who used it to help healing a wound (not very deep but large scratch after falling from a mountain bike) and he says it helped, don’t know about that (he is a doctor)
This thing was using an IR laser diode with some optics on it to make wider beam plus some additional red and IR diodes (hard to tell what they were because of some cloudy convex lenses on them).
It was using them at relatively high power I guess and PWM to adjust average power by changing duty cycle, it could also change frequency from few to few hundred Hz – no idea what the purpose of that.
I guess because it was designed to also help with muscle stimulation it has to reach deep, so high power, but not to burn skin so PWM to keep average low.
It was old device and laser diode could be needed to get required power, maybe current IR LEDs are good enough.
With eyes I would think you don’t need much power to get where needed but I didn’t see in any of these articles anything about power they used. Did I miss it? Anybody knows?
This store have a lot of Red Leds
Hard to find wich are originals Cree,maybe the more expensive
Right, thank you!
I’ve just found that RS componentes in Spain has a whole list of LED products, from reputable manufacturers with datasheets and so on. Then there’s no crazy delivery costs for me as I’m based here.
https://es.rs-online.com/web/c/?sra=oss&r=t&searchTerm=670+nm+led
I still think a flashlight based solution would be the most practical one though. Does anyone have any good info about making custom flashlights for a beginner like me?