Can we make the ultimate LED headlamp?

I've been mulling this over since before I found CPF. Here's my current "Ultimate LED Headlamp". It's simple enough that I might be able to build one.

The guts of my "ultimate LED headlamp" would be an aluminum heatsink/chassis mounting a 5-watt and 1-watt LS side-by-side with a single 5mm LED in between. It would also mount a 3-position switch and the required voltage regulation circuitry. Ideally, this heatsink/chassis would be hinged to a plate attached to the head harness so you could aim it.

Apparently a common 9-volt battery will drive a 5-watt LS for about 20 minutes (see the 120 lumen pocket light thread). You could comfortably suspend one to four 9-volt batteries from the back of the head harness. Couldn't you use step-down voltage regulation to drive the 1-watt LS and 5mm LED?

This setup would allow the user to choose between the 5-watt LS (for hiking off-trail or trail running), the 1-watt LS (for hiking on trails) or the 5mm LED (for camp chores and map reading).

Driving the 5W LS with a common 9V alkaline battery is convenient because the internal resistance of the battery is sufficient to limit the current going to the LS, so that you don't need any additional circuitry.

If you also wanted to be able to drive a 1W LS, you would need appropriate step down circuitry, similarly for the 5mm LED.

It seems to me that if you are going to have the step down circuitry, you might as well use it to drive the 5W LS, which would mean that you are no longer limited to using single 9V alkaline batteries; you could use any supply with sufficient voltage. A properly designed step down circuit would permit you to dim the 5W LS, which would function reasonably down to about 50mA (about 4x the power of the standard 5mm LED (which would be about 25mA, but also at half the voltage) ). So you could get all of the desired light levels with a single 5W emitter and the appropriate circuit.

Combine this with a single _red_ 1W LS, again on a dimming circuit, and I think that you would get _my_ vote for the ultimate LED headlamp.

-Jon

Thanks. Electrolumens responded similarly to one of my posts in the "120 lumen pocket light" thread. As I said in that post, I am a novice flashaholic A single 5-watt LS with voltage regulation and multiple brightness settings would be better.

Your idea of ultimate would be useless for caving, backpacking, search and rescue, etc.

What's the point of having a Tactical headlamp???

Silviron's Arc LS 4AA headlamp mod is nearly perfect, since he rewired the battery pack to 2 x serial and 2 x parallel, doubling the runtime, when used with 4AA. It can be used with 2AA. Using Lithium AAs you get 12+ hours of bright light.

In order to make a 5 watt LS practical in a headlamp, you would need to use at least a 2D pack. 2, 3, or 4D would work fine. The Coleman Peak 1 headlamp uses a 2D external pack. This would be needed to get decent runtime. Even C cells would give reasonable runtime.

Your concept is a good one, with the 3 different LEDs, but I object to your choice of batteries, with the reasons stated above. I think others would agree.

A 5 watt LS can be used with 3 volts.

Ok ok . . . AAs then

I had missed Silviron's ARC LS mods here: http://az123.com/darksbane/arc_ls_mods.htm How about KLX versions?

I've gone from a Lithium Easter Seals headlamp to a Petzl Zoom, to a couple other lights to a Tikka over the past few years. The Tikka is OK, but is you want to look at something far away you are SOL.

I find 3 LEDs and fresh batteries sufficient for night hiking on trails, but I find I occasionally want more light. (Apparently I'm not the only one who wants 5+ watts on occasion. Silva makes several 5 to 10 watt headlamps.) An ARC AAA is more than sufficient around camp.

I'd like to be able to adjust brightness to my needs (three settings would suffice) to balance brightness and runtime in a small lightweight package. A 1-watt LS with optics would probably do everything I need. I'm working on a Rayovac 3-in-1 mod (waiting on the LS), which might balance my priorities reasonably well.

Due to relatively low cost of SF KL3 and its built-in regulator and supports 6v to 9v, it would be ideal headlamp module. A good mounting and switch system with 4AA on the back and options to use detached powerpack such as 6 AA or 4 C/D cells or even with 6 x 123 (9v in parallel) for users who want light weight and long runtime (15 hrs).

Besides, when SF further develop newer (5W?) LED module, it is likely that it would be compatible with its 3 cells light thus compatible with the headlamp mounting system. You could focus on designing a perfect mounting system instead of circuits, LED quality, heat issue and reliability as SF will take care all this.

I think the Switchback would provide good base (waterproof external battery pack and good headband) to start with.

Anyone take the challenge

Alan

By the way, the same mounting system would be capable to use SF P60 to P91 if correct battery pack is used. It might not be too desirable for general headlamp usage with such bright and short runtime. It won't hurt to cover larger market sector since no extra work is required.

Is it a dream?

Alan

I think Alan is right. I started a "Surefire Headlamp Accessory" thread HERE a while back. One alternative would be an "extension cord" that would permit you to keep the SureFire body/battery holder and switch in your pocket. I like the switchback idea, too.

Dilettante, you beat me on KLx idea while I was typing my post I prefer KL3 instead of KL1 for 2 reasons:- 1) It has more options with current SF parts. 2) If SF develop 5W LS module, it is more likely in size that compatible w KL3 instead of KL1.

Alan

I'll take whatever I can get

I vote for AA's as your battery source, simply because they pack easier than C or D, and they make lithiums in AA. Among other things, I'm a backpacker/climber, and weight (or lack there of) is high on the list of requirement.

I was excited when Princeton Tec came out with the Switchback, since it's got the abilitly to go lightweight, using just the internal battery source (2 AA) or you can plug in a belt pack for caving/summiting/cycling, or any other time you want lots of light for extended periods of time and are willing to lug the weight of C or D batteries. Of course, it wouldn't be ideal unless it had an LS in place of the incandescent bulb

Charles Bradshaw,

why did you say that dilittante's suggestions would, "be useless for caving, backpacking, search and rescue, etc." ?

I assume the comment from Charles is directed towards the lifetime of the unit. As always there have to be a trade-off between brightness and duration. It is also a hassle with an extra wire when moving through bush and/or tight areas.
In our 250-500km adventure races we have found three LED's to be sufficient only when moving along well established trails/tracks. Then also a minimum brightness of Opalec Newbeam type strength is required. Anything less and the risks to ankles etc. becomes high.
Ideal headlamp? A Newbeam module linked to a LS driven at around 260-300mA. What about a focusable "flip down" (SF beamshaper style) or "slide over" acryllic lens to increase throw?

Originally posted by Charles Bradshaw:

Your concept is a good one, with the 3 different LEDs, but I object to your choice of batteries, with the reasons stated above. I think others would agree.

A 5 watt LS can be used with 3 volts.

Click to expand...

<font size="2" face="Verdana, Arial">I agree that the 9V batteries are a bad choice, since they are expensive and have poorer energy density than AA batteries. However a properly designed system would be capable of running from any power source with the appropriate voltage range.

FYI the 5W LS has _two_ junctions in series, and requires considerably more than 3V to run, even if it is being underdriven at 1W.

-Jon

Plinko, that was mainly due to battery choice. (I think ) Runtime is important for these activities, where longer is better. Both the light housing and the battery housing need to be at least 'frog choker' proof.

This is why I like Silviron's 4AA series/parallel 'adult' Arc LS headlamp mod. I bought one from him, simply for the fact of doubling the runtime (12+ hours bright with 4 Lithium AAs). It can also be used with 2AAs. Note, the runtime is with the rev1 circuit.

I also have a Solo withe the LED module for dimmer but longer runtime.

I plan to use the 2D external pack from my Coleman Peak 1 Expedition headlamp and mod it and Silviron's mod with inline power connectors to further increase runtime. Being able to switch between power sources as needed is important to me.

When the Versalux PR2 LED 3 volt bulbs arrive tomorrow, I will see if they work in the coleman and 2D mag.

Focusability is nice, if done properly. The point of an external battery pack (belt), is an option for the proper situations and the extended runtime.

I don't know what would be best for the extended runtime: external pack or rear mountable packs for AA and C (D is too heavy for this), which would be user swappable. External packs can be a hassle, as others have pointed out.

At any rate, we are discussing a concept and throwing up ideas and the different needs to refine it.

I'd love to see Silviron offer a KLx version of his 4AA series/parallel 'adult' Arc LS headlamp mod. My main concern with this approach is weight. I don't have an ARC LS or KLx but they look pretty heavy.

I like the idea of a flipping/sliding lens idea. Someone also mentioned a moveable acrylic ball in another thread. Then you could get throw as needed. If you used a KLx head you could make a flippable lense out of a beam shaper.

What about reflectors? Someone suggested using one of the 3" or 4" reflectors for a carbide lamp with an LS. The 5 and 10W Watt Silvas have a pretty big reflector. I wonder how an LS Mod of one of those would work?

Anyone here checked out the Speleo Technics lights made in the UK? See http://www.speleo.co.uk/. Expensive but interesting combinations of battery technology, LEDs and incandescent.

NamTinker's Zoom modification is pretty cool, too. The battery holder of the Zoom and Zoom Zora give you the flexibility ofsetting up 4 to 6 AAs in various configurations or using a 4.5 volt 3LR12. It would be even cooler if you could adjust the brightness from Newbeam brightness to full on 1 or 5 watt LS brightness. I wouldn't want anything much heavier Zoom with a 3LR12, though.

Thanks everyone for the comments on my headlamp mods-

I'm not sure about the KLx (don't have one, probably won't be able to get one for a month or four, even once they become readily available)

It MIGHT work on the existing LS mod (threads are the same, at least with my E2) the contact distance is different though- so that may have to be altered, and would be easy enough to do.

If someone wants to loan me a KLx head, I'll make a prototype to make sure it works, then send your KLx head back to you. (Is the clip easily removable / replacable without damage?)

Haven't done much in the workshop the last week and a half, but should be able to get back to work there in a few days. I think I'm pretty close to being able to offer the ARC LS / Maglight adapters at a pretty reasonable cost.

The Arc LS head is extremely lightweight, Dilletante, not to mention, small. (My Cyan LS is due to arrive today: drool!).

Silviron, Thanks for the update on the LS/Mag adapter.

LS LED and reflectors: at least with the low dome Pro Series you get a greenish-yellow corona around the center spot. You do get a nice smooth spot and decent side light out of a 2D Mag (my only Mag). Actually, with new Titaniums it is far brighter than with what turned out to be very tired Radio Shack alkalines.

Charles, greenish-yellow corona from your ProSeries bulb, eh? How long ago did you buy it? I got one about a year ago and it was the whitest LS I've owned! I got gutsy one night and put it in with 3 C batteries (4.5v) and man, was it bright! It aslo got pretty warm thogh, since there's not much of a heatsink there on the MagLight bulb stem. Nice easy way to get an LS into a Maglight though.

I got it just last month, Plinko.

So the ideal LED headlamp would be waterproof, have a 1 or 5w LS and a switch for brightness, a small rechargeable battery inside the 'head', with a plug for a larger belt-pack that can run the light and recharge the batteries. With the rechargeable batteries in the head, and a low-power switch to allow users to replace the big batteries in the belt-pack without doing it blind...