Surefire L4 5W released!

[MicroE]

Darell--Maybe I misunderstood you.

I'm not sure that there was a huge leap in technology between the 5mm Nichia and the LS 5 Watters.

Did the efficiency of the chips increase or was it simply that somebody was willing to make bigger chips and heatsink them properly?

I would venture that the real leap in technology here was the ability to make a WHITE LED (or really, the blue LED with phosphorescent coatings).

The heat problem of LEDs won't be solved as easily as it was for CPU's. There is no extra power or room available for a big heatsink/electric fan/Peltier device inside a flashlight.

As it is, my Arc LS gets (IMHO) noticeably hot after a few minutes of runtime. My 5 Watters can fry eggs when they are running.

 

[Brock]

OK, the beam is a bit larger then an E2, but it is throwing more lumens, I would guess 65-70. The sample I have is pulling about 5.2w total, so I would guess maybe 4 to 4.5w at the LED. It has a sort of shadow on the center of the beam, probably the shadow from the center of the LED. At first it bugged me, but you don't notice it after you use it a bit. I would have to say the beam size is very close to a P61, larger then the P60. The first thing I noticed was the color temp is much nicer then the KL1, much more white rather then blue/purple. I Hope Surefire continues in this direction. Now if only it had a dimmer on it /ubbthreads/images/graemlins/wink.gif It is regulated, and runs about 65 to 70 min on SF batteries in regulation, and much longer at a much reduced level. What did I miss Al?

Oh, for those that want to see it the PDF for the L4 is at
L4 PDF
Sabby or Darell feel free to shorten the link /ubbthreads/images/graemlins/wink.gif ** - Done. Darell. **

And yes it does get hot, I got 140F or 60C, to hot to hold, it got to that temp in about 15 min and stayed there. Besides testing I never had it running that long.

 

[milkyspit]

Perhaps I'm totally mistaken -- and if so, someone please correct me! -- but I've been under the impression that the "traditional" Nichia 5mm LEDs are far more efficient (amount of light per mW) than any of the Luxeons. This is also manifested in the lower heat generation (assuming not overdriven) and longer MTBF. However, the two problems with Nichia are their short throw and the need to use literally dozens of them to achieve greater amounts of light, which is of course impractical in a small flashlight head. For these purposes, enter the Luxeon, albeit with some loss of efficiency.

I live out in the country, in the middle of nowhere really. We are prone to a few power outages each year. For my purposes, I think of Nichia in terms of "power failure" lights, meaning I want something that will light a room for pretty much forever if left on and stood on end (TurtleLite II is great for this), and Luxeon for a light I can take outside to see whether that weird sound I heard at the edge of the yard is a deer or a thief, or whatever. I do prefer LED to incandescent in all cases, though, based on whiter light, more of a flood effect, etc.

For the latter use (outdoor "scouting"), the Surefire L4 sounds mighty tempting. I just wish the batteries were more affordable!

Does this make any sense, folks?

 

[Size15's]

What did Brock miss?
The ability to flash the L4 is a stunning option. I mean I don't think people are prepared for the colour of the light and the amount of it.
SF123As are $1.25 each.
With the L4 (KL4), the batteries have longer useful lives due to the regulation.

Al

 

[Darell]

[ QUOTE ]
MicroE said:
Darell--Maybe I misunderstood you.

I'm not sure that there was a huge leap in technology between the 5mm Nichia and the LS 5 Watters.

Did the efficiency of the chips increase or was it simply that somebody was willing to make bigger chips and heatsink them properly?

[/ QUOTE ]
I should probably just stop typing, since I rarely make sense even to myself.

My point was the difference between a 20mA 5mm LED from a few years ago, and the same spec LED today. We didn't have a bright enough LED to use in a respectable keychain flashlight until relatively recently. But enough about that....

As for the 5W units, I believe that a leap in efficiency is coming in the not-so-distant future - according to what I've been reading. This translates into less power converted to heat, and more power converted to light. Same ~5W draw, but cooler and brighter. And the same tech can be applied to all chips across the board.

Anyway, none of this belongs here. The L4 is absolutely cutting edge for a production flashlight. I've tried not to order one, but the finger keeps getting closer and closer to the VISA.

 

[uhammer]

[ QUOTE ]
Brock said:

And yes it does get hot, I got 140F or 60C, to hot to hold, it got to that temp in about 15 min and stayed there. Besides testing I never had it running that long.

[/ QUOTE ]

Is that only the head that gets hot? Or does the entire body of the E2 get to 60C? TIA,

 

[Size15's]

The bezel gets very, very hot and the body just gets very hot.

Al

 

[brightnorm]

[ QUOTE ]
Size15s said:

...The KL4 does not have the reach of the E2e - the 5W Luxeon source is too large to get a tight beam from this diameter reflector....



[/ QUOTE ]

So it does have a reflector. Would it be possible to put a tiny cone shaped funnel with the large opening directly over the LED and the small opening with a smaller diameter than the LED emitting its point-source light into the main reflector which can then focus what it sees as a "smaller emitter" into a tighter beam?

Brightnorm

 

[paulr]

As long as 5W emitters cost $30+ each, I don't imagine them showing up in any mass market lights (Dorcy etc). Also, I see 5W as being more useful in a long-throw type of light than in a short-range flood. I wonder if there's some way to use fancy focusing optics to get a narrow angle from a KL4 sized bezel. For now, the L4 is awfully tempting on pure technical grounds (such a tiny LED light with so much output), but I'm maybe more interested in a light with a bigger bezel (30mm optic McLux head, Space Needle II, or something like that) as my first 5W LS light.

 

[Darell]

[ QUOTE ]
brightnorm said:
So it does have a reflector. Thanks for that info Al.

BN

[/ QUOTE ]
Hey, I said that several *minutes* before Al did. /ubbthreads/images/graemlins/smile.gif

"Reflectored LEDs are a couple of months old now - they can only get better. Probably WAY better."

This really is the beginning of "how it's gonna be." And you can quote me on that. Never mind, I already did.

 

[FalconFX]

My Visa is painstakingly close to the keybard right about now...
It's just the point of waiting it out for a KL4 or getting the L4...
In any aspect, I'd figure something like a 5W in a E2e body would be insanely hot to handle if you use it from start of batt life to death... My nachos with it is there's no dimmer with it to keep my hands from flaming...

 

[Skyline]

Does the L4 have thermal protection circuitry? Does running the L4 continuously for 1 hour, 2 hours, etc cause permanent damage to the LED?

 

[MicroE]

140 degrees F.
Ouch.
I think that the anti-scald devices on hot water lines limit the water to under 120 degrees F so children don't get burned.

At that temperature I'm not going to be walking around the house with an L4 clutched in my teeth!

Darell, I also hope that more efficient LEDs are coming soon.

 

[Darell]

Yeah, this is one that my daughter won't be playing with! I don't think I'll let her play with Choua's nachos either.

 

[lemlux]

As far as efficiency goes, I wonder what the junction temperature is on a light with a 140 degree F head. (Hotter than 20 degree's C optimal, in any event.)

 

[brightnorm]

[ QUOTE ]
Darell said:
Darell--Maybe I misunderstood you.
....As for the 5W units, I believe that a leap in efficiency is coming in the not-so-distant future - according to what I've been reading. This translates into less power converted to heat, and more power converted to light. Same ~5W draw, but cooler and brighter. And the same tech can be applied to all chips across the board....

[/ QUOTE ][/i][/b]


I agree with Darell. We already have bright, but efficiency is the key.

(Bin Codes courtesy LEDModMan):

Flux
U (average)87.4 to 113.6 lumens - Av 100Lu = 20 Lu/W
V (good)113.6 to 147.7 lumens - Av 130Lu = 26 Lu/W
W (jackpot!)147.7 to 192.0 lumens - Av 170Lu = 34 Lu/W
X (you wish!)192.0 to 249.6 lumens - Av 221Lu = 44
Lu/W

"W" has an average flux of 170Lu and a maximum of 192.
192 div 5W = 38.4 Lu/W. At that level of efficiency 1.6 watts would yield 61.44 lumens, slightly more than an MN03.

So, a 5watter driven gently and relatively "cool" at 1.6W as bright as an E2E, and with a regulated burn of perhaps 3hrs+. And that's just the beginning.

Here's an idea. Don't laugh if its absurd, I'm not a techie like you guys:

"....Would it be possible to put a tiny cone shaped funnel with the large opening directly over the LED and the small opening with a smaller diameter than the LED emitting its point-source light into the main reflector which can then focus what it sees as a "smaller emitter" into a tighter beam?"

FROM FALCONFX:
In any aspect, I'd figure something like a 5W in a E2e body would be insanely hot to handle if you use it from start of batt life to death...

My 5W modded to KL1 by cm on an E2E is no problem to hold a few minutes at a time. If I want longer on periods I may remove the rubber from a Brinkman and wrap it on the E2E

Brightnorm

 

[Darell]

[ QUOTE ]
brightnorm said:
If I want longer on periods I may remove the rubber from a Brinkman and wrap it on the E2E


[/ QUOTE ]
BN - Please don't do that! You'll insulate your hand from the heat, certainly, but you will also be insulating the heat from the environment. If the exterior of the light can't shed the heat, the temp will likely not stabilize until a much higher, more damaging point is reached - if at all. You won't be seeing any plastic 5W lights until we've increased efficiency WAY beyond what we have today.

Better to do your best Michael Jackson imitation and wear a glove on your flashlight hand. Or do what I do, and play hot-potato with the light. /ubbthreads/images/graemlins/grin.gif

 

[Brock]

Yes, sorry that is the temp at the head held in a jig to meter the light output over time. The body gets warm, I don't remember what it was maybe 110 to 120. The body is "holdable". I have to ask though why someone, besides myself or Al, /ubbthreads/images/graemlins/wink.gif would be walking around a house at night with this light. It is meant to be used tactically, not constant on use.

What else, oh if you put the KL4 head on a E1x body it is about 1/3 as bright as the KL1, and if you run this baby on 9v, watch out! It is blinding! I can say it isn't regulated at that voltage because it is SO much brighter. I also don't know how long it would run at that voltage without melting. Although if you only want to flash it... Hummmm...

 

[desmondpun]

According to Brock PDF, only 65-70 Lumens. Underdrive or Surefire realistic/conservative measure?

 

[TrevorNasko]

I ordered one overnight and i hope i will get it by the end of next week.