Glass aspherical lense. What to do with it?

[nickz]

I got my hands on an old glass aspherical lense from an old micro film viewer. It is 2.732" in diameter so it does not drop into a mag. I tried hand focusing one of my seoul malkoff devices lights but was not real impressed with the results. Anything else I can do with this thing ?

 

[2xTrinity]

I got my hands on an old glass aspherical lense from an old micro film viewer. It is 2.732" in diameter so it does not drop into a mag. I tried hand focusing one of my seoul malkoff devices lights but was not real impressed with the results. Anything else I can do with this thing ?

Cree XR-E is a much better choice for aspeheric mods, as the built-in dome projects a lot more light forward whereas the Seoul projects more to the side. The seoul is better for use with reflectors, the Cree is better for use with optics (color rendering issues aside -- I'd say Cree is better for color in either case).

The key however is that you will need to do one of the following things -- use a primary converging lens to direct the light from the LED into the aspheric, or find an aspheric with a very short focal length, some of the stuff at Surplus shed has a focal length that is shorter than the diameter of the lens -- that's ideal as the lens will capture a greater portion of the beam that way.

I'd love to see someone project an LED or even an HID/Incan with a huge diameter fresnel lens -- collimation could be absolutely incredible.

 

[nickz]

Eh, for me it is too much work to build a practical light that I would use. I will likely post it in the buy sell trade. How is one sure it is ACTUALLY aspherical ?

 

[chesterqw]

the surface must not be spherical, thats for sure...

 

[Long John]

Important too, don't use it combination with a reflector. That means, the collimated beam of a reflector doesn't help to capture mostly light by the Lens.
Only the Cree and the Lens in the right distance will give a perfect result.

Best regards

____
Tom