Aspherical lens on Incan.

[nightstalker101]

I am looking into getting one of those 55mm dia. 37mm focal length aspherical lens. Do these work on incandesents? I want to give my 5761 more throw. Are you supposed to remove the reflector or not? Any info on these type of lenses would be great. Thanks

 

[zk188]

You would just get a projected image of the filament unless the bulb is well frosted and ulike LED's the light is projected 360 degrees.Making it hard to capture the light.

 

[nightstalker101]

So do you remove the reflector?

 

[zk188]

Yes i think so.You might also want to put some kind of mirror behind the bulb to recapture some wasted light.

 

[Gunner12]

If you use the reflector with a asperical lens, then you would get an image of the filament, then a ring of darkness, the a further ring of light, My guess is there should be about 170 degree of light with the reflector.

 

[nightstalker101]

If you use the reflector with a asperical lens, then you would get an image of the filament, then a ring of darkness, the a further ring of light, My guess is there should be about 170 degree of light with the reflector.

What about useing a stipple reflector? Are there any other ways to affectively use a aspherical lens on a Incan.?

 

[Wincet]

I think you can with a octagonal diffuser, but then I don't know if you are actually gaining anything.

 

[sysadmn]

What about useing a stipple reflector? Are there any other ways to affectively use a aspherical lens on a Incan.?

I'm playing with the DX 26mm aspheric and a variety of DX p60 assemblies. When you get the filament in focus, the stippling on the reflectors creates a pattern that looks like a cobblestone drive, with multicolor grout. It would be a great self defense light if your attacker is on acid. :thumbsdow Still, the lens was $2.50, so no great loss.

With the 52mm lens in a Maglite, you can slightly defocus to get a useful blob of light. Still, I prefer the MagLed in a 3D to a 4D Xenon Magnum Star driven with 5D, when both have the same aspheric. THe Magled produces a square image that's intensely bright; the incan a rectangular squiggle that is less so.

 

[2xTrinity]

What about useing a stipple reflector? Are there any other ways to affectively use a aspherical lens on a Incan.?

What would be needed is an elliptical reflector, essentially a reflector with two focal points -- the filament would be located at one, and the lens woudl be located at the other. A diffuser would be needed as well to smooth out the beam. This is essentially how projectors work.

Flashlights on the other hand, which are not designed with lenses in mind, use a parabolic reflector (a special type of elliptical reflector) in which the filament is located at one focal point, and the other focal point is at "infinity", so that the light exits straight out, rather than re-converging at some later point.

For hobbyists who have no way to engineer their own reflectors, it makes a lot more sense to use an LED like a Cree, in which most of the light naturally is projected forward, into the lens (rather than being emitted in all directions). Conversely, a Cree is generally a poorer choice for use with a reflector compared to a wider-angle LED, or incan (in terms of generating throw).

 

[lctorana]

What would be needed is an elliptical reflector, essentially a reflector with two focal points -- the filament would be located at one, and the lens woudl be located at the other.

I get it!

You know I won't rest until I find one, now...

 

[jimjones3630]

asphericals on Incan. got interesting and bought several from surplus shed. good prices. they do have the fish eye type as discussed in this thread

http://candlepowerforums.com/vb/showthread.php?t=169371

the one have now on 2cM@g61 is 50.8mmx254mm fl. Edge thickness is 3mm, center thickness is 5.5mm, with a smo reflector and seems to make the hot spot wider at 200yards.

http://www.surplusshed.com/pages/item/pl1018.html

put a 52mm, 100mm fl on 35w 6v tungsram driven with 3x A123's over 2000 tl and liken the effect, makes hot spot wider without lessing the throw as a heavier coated reflector would.

http://www.surplusshed.com/pages/item/pl1062.html

enjoy jim