Questions about optics for XP-G's

[EricZ]

I am researching xp'g's and the 10mm square optics like Carclo's to build a headlight unit for my custom Buell XB12 turbo motorcycle. I am not concerned with having a good cutoff like a DOT apporved lamp would provide for low-beam but I do want to end up with light that both shows distance and has some width.

I would like the headlight design to have two side by side vertical strips of 8-12 led's with optics. One strip could use the 10mm elliptical optics and the other use something like the tight narrow with each strip being adjustable for aiming.

I would like to know how far the 10mm optics are capable of throwing light and how to distribute the optics to the 16-24 total leds.

I also am thinking of using tinted lexan for a protective lens and am not sure about how the lighting will be affected. Any suggestions and/or pictures would be great!! Here is a pic of my buell:

 

[Kestrel]

Running 'search' for "XP-G optics" yields the following results, for starters:
http://www.candlepowerforums.com/vb/showthread.php?t=243940
http://www.candlepowerforums.com/vb/showthread.php?t=251111
http://www.candlepowerforums.com/vb/showthread.php?t=257109
http://www.candlepowerforums.com/vb/showthread.php?t=245219
http://www.candlepowerforums.com/vb/showthread.php?t=270848
http://www.candlepowerforums.com/vb/showthread.php?t=255068

You may find some good info in the above threads, and might find it helpful to post follow-up queries in the most applicable one(s)?
Oh, and :welcome:

 

[John_Galt]

The XP-G's, while bright, do not have the surface brightness or optics available to throw very far. You're going to want to look at XR-E's for tighter optics.

 

[Curt R]

As with any LED, the importance of a proper optic determines the actual throw as measured in Candela and
the ratio of input of the bare LED to the output with the optic/reflector.

With the XP-G and a 10 mm optic the ratio is about 9.5 to 1.
The IMS 17 mm reflector ratio is 29 to 1.
The IMS 20 mm reflector is 50 to 1.
The IMS 26 mm reflector is 75 to 1.
The Seconix 37 mm optic is 140 to 1.
A 58 mm reflector is 350 to 1.
(A Luminus SST-50 LED with the same 58 mm reflector is 105 to 1.)

The Peak FR400 using the XP-G has a Candela output of 14,500 and a good throw of over 600 feet.

The XP-G at 1.5 amps with the 58 mm reflector will give 31,500 Candela at 300 + Lumens.

The SST-50 at 5.0 amps with the 58 mm reflector will give 31,200 Candela at 1200 Lumens.

Forget about using a dozen XP-Gs and 10mm optics for your application.

Curt

 

[mds82]

I have been trying to do the same for a while, and there are no optics that really work as a low beam . none of the optics have a cut-off and you will blind drivers.

The best thing i've found - put 6 Cree XP-G's, right up against each other, wire them up, then put a piece of metal or something very reflective directly above it. This will make a perfect cutoff while doubling the light that goes to the lower half. for a power supply, i am using a 3 amp supply, running 3 led's in series, and the 2 sets in parallel. put them as tight together as possible, aka with them touching

- Next, take a aspheric lens from an old headlight, something thats around 80mm in diameter, and mount that infront of the LED's. That will give you much more projection, keeping a perfect cutoff beam, and give you a nice wide beam as well.

I'm doing the same thing with my fog lights, and i am going to try and get pictures soon.

 

[znomit]

Nice bike, always wanted a Firebolt but too attached to my Guzzis.
Speaking of led headlights and Guzzis...

Anyway. As mentioned the 10mm optics wont provide the required throw. I used three on my bicycle and they weren't that good, looking at making some marker lights for the Vespa with them. Possibly the 22mm ledil CXP optics might give enough throw, though I'd mix in some XPEs for better throw.

mds82 did a 'busa light... over on the vehicle light forum.... see it doesn't throw as well as the stock.
http://www.candlepowerforums.com/vb/showthread.php?t=228933

 

[kan3]

I'm still playing around with a design for dirt bike and SM. I settled on 5 cxp with 3 of them being RS and 2 OS. The housing would be similar to the original light so it can be rotated up and down to aim the light. I'm pretty happy with the optics/throw and really couldn't tell much of a difference when I put 3 xp-e in place of the xp-g for the RS optics.

Still really isn't meant for street as it'll be very bright to oncoming traffic...entirely off road stuff. It's going to be hard to design something that won't impair other drivers.

I do have a couple of comments on that busa light. The first being he used optics I wouldn't and I felt it was a waste. Though, judging by the pictures I felt that it was an improvement over the stock for a couple of reasons. He may have gave up some throw but the output was more than enough to be useful down the center of the road. At the same time he increased the width and throw of the beam on the edges which allows the driver to spot deer and other animals much easier. Where I live, my primary concern when driving home is deer and that LED busa light is silly but would do a better job.

 

[mds82]

any update?

 

[EricZ]

Thank you for all of the help! I have decided to look more at the larger diameter optics for better throw but still include a few of the 10mm optics for some flood lighting. My current headlamp housing is about 3" wide by 4.5" tall and the positioning of the led's will determine the look of the headlamp assembly when everything is put together.

My brother has also been giving me advice as he has build some really awesome mt bike headlights using leds. He recommended an easier route of choosing a driver and building the led array around the capability of the driver rather than designing the led array and trying to find a driver to work with it.

What I am now trying to figure out is of the larger diameter optics, what will allow me to throw light far down the road and still fit enough led's in a attractive arrangement within the space restrictions while also providing enough total light?

Can anyone post some links to images of the larger optics and their beam shots?

 

[dhpage]

Hi!

I was made led headlights for my KTM Duke, some pictures here: http://picasaweb.google.com/dhpage.fw.hu/LedesMotorlampa?feat=directlink

Sorry for no english titles, but feel free to ask questions!

The original lamps modded with 3-3 MC-E leds. One of for high beam, and one for low beam.
The lamps has 65mm glass lens (projector), heatpipe pc northbridge coolers takes the heat from leds, and my own designed boost electronic drives the leds (60w power from any voltage between 8-30V, thermal management, microcontroller, etc.).

Dhpage