Hi, I have been thinking already for quite sometime, to build my own headlight (flashlight and mount to head and battery to backpack). This thinking is because I have looked for various options for already on sale ready flashlights, but those good ones are expensive with good light distribution.
For now I have gathered some information and decided that I want my headlamp to be configurable, so that it can achieve brightness of over 6000lumens. Altough I would be using this lamp propably mostly at 1000lm, it is nice to have more power if needed. Because the lamp will be used at 1000lm most of the time it should have good light distribution and so need good lenses!
Here is my list so far what I was thinking:
sst-40 leds (four pieces to achieve +6000lm peak brightness)
drivers for these leds (18v input from battery and output of 3.6v 5A for each of the leds)
a copper heatsink
pwm controller, which I could use with esp32 to generate different power modes for the flashlight.
battery (consisting of 4s2p 8cells of 21700 cells)
optics (lenses, which I have been thinking what would be good for seeing far but also not too spot to achieve good overall performance)
frame, still looking for it (need to find something good to mount these pieces or then 3d-printing.)
Hope I did not miss any components from this and if anyone has any suggestions I will happily take them into concideration. This project is done for saving a bit money (not really if counting working hours propably but anyway)
Thanks, That is also one issue and I was thinking to use copper heatsink, but that propably isnt enough for heat distribution, so thats one issue I need to overcome still and dont yet have a proper solution
Headlamps generally do not need to be bright because the stuff you are illuminating is directly in front of you at arms length. Your eyes will adapt. If you are caving or doing construction and wearing a helmet, that provides a better platform on which to mount a heavier device, but again, less is more. Lighter weight headlamps are usually preferred. Without active cooling, a small heatsink will saturate with heat pretty quickly, so high output will be limited in duration.
You may be right since I do not have much knowledge in headlamps. What configuration would you suggest, since it would be nice though to have even couple thousand lumes (close to 3000lm) which is still pretty much wit optimum light beam. I would like to then maybe also build another one for long distances (a normal flashlight maybe but thats a separate case then!
Make yourself at home, Mrhamu!
8 x 21700 headlight doesn’t sound very practical.
Many (most?) BLF members think that 1 x 21700 is too heavy for a headlight.
Just chiming in: if you want 3000lm of output, you must understand that it has to be a brief burst, likely under 20 seconds, because a headlamp with any reasonable weight and volume does not have enough heatsinking to handle this much power, regardless of the material used. Comfortably sustaining 3000lm requires a light weighing around 1kg, which is not suitable for a headlamp.
Now that we got that out of the way: the XHP50.3 HI and XHP70.3 HI are both capable of producing a 3000+lm burst from a single emitter. Use the 70.3 HI if you want to prioritize efficiency and sustainability, and use the 50.3 HI if you want to prioritize throw.
Given that the power usage is limited, there is not much need for a separate battery pack unless you want extreme runtimes. A good headlamp might comfortably sustain ~500lm with ~1A of current, which is 4 hours of continuous runtime from a single 21700 cell. I think changing the battery once per 4hr is easier than designing an external battery pack, and there probably already exist many headlamps capable of this in stock form or with minor modifications.
Thanks for all the responses I will look into this! Are there any “superior” lenses (optics) for these lamps which produce good light distribution?
I have now astrolux ec03 which is good, but cant have both hands free when using it, and it does not have enough battery for me. I then have on my bike 2x purelux terrain (other one is flood and other spot) but I can not see anything when i turn my head back or when im walking, since the lamps are on my bike.
Thanks, I will look into it but for now i will stick with making one, because I want to learn also something during the progress and I will propably almost “copy” something which some users have done here, since it will be my first headlight build
Some TIR lens manufacturers are Ledil, Carclo, Khatod, Gaggione. Ledil and Carclo optics are distributed at Mouser and Digi-Key among other places. Lenses from Chinese producers can be found on AliExpress. Convoy sells some TIR optics, reflectors, glass, and also drivers and LEDs. Convoy products can be purchased from AE but also from the Convoylight.com website. Check out KaiDomain for all sorts of DIY flashlight components, glass, optics, etc.
Wide angle TIR optics can produce a floody diffused output with no hotspot, which might be desirable. Reflectors and narrow angle TIR lenses tend to produce a beam with a central hotspot, along with a surrounding corona and flood. Reflectors are generally SMO (smooth), or OP (orange peel) which helps to blend the output a bit, creating a softer transition between the central spot and the surrounding flood portions of the beam. 20mm Carclo triple optics are a way to get a lot of output from a small optic. Carclo also offers 24mm quad optics. The quad lenses offered by Convoy may be preferable to the Carclo quads.
Various LEDs can be used depending on what you’re going for. Nichia 519A tends to be the high CRI led of choice at the present time. It is available in a lot of different color temperatures and can easily be dedomed to alter the characteristics, e.g. reduce CCT and DUV and create a smaller hotspot within a given optic.
Thank you really much this is what I needed (hopefully) since I could not understand all of the terms (im new to this), but I will google them and read that so that I can actually understand all of it. And yes I think I will use reflectors to have a better light beam so thanks also for that! I will look also into that specific led, since it seems to be good and I could use it in my project!.
