Reflector Aspheric hybrid - anybody try this?

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Pip
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Reflector Aspheric hybrid - anybody try this?

Has anybody tried to make a reflector – aspheric hybrid flashlight? A reflector flashlight converts about half (guessing) of the light to throw, half to spill. An aspheric flashlight converts half to throw, and wastes the other half.

Can you add an aspheric lens to a reflector flashlight suspended from the lens in front to convert the spill to throw?

Reflector light, red is throw, blue is spill.

Added aspheric converts spill to throw (blue dashed lines).

Any thoughts?

Pardon the rough drawing, the kids flattened all the tips on my markers.

netprince
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I’m pretty sure I’ve seen TIR lenses that are shaped like your last drawing and produce a nearly 100% throw pattern. If you look down into it from the top you can see the aspheric lens shape in the center.

Agro
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You can find some experiments like that here:
https://budgetlightforum.com/node/64282

Yes, there are numerous TIR lenses like that as well.

jon_slider
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> Pardon the rough drawing, the kids flattened all the tips on my markers.

the drawings are great Smile

I just put an aspheric on a mule
.. works great for my intended use, close work.

it did not work with an AA Tool w reflector, makes a beam with a dark ring around it:
example:

the other issue is that an aspheric lens at reflector distance makes a very small hotspot
example:

the term Aspheric means different things to different people. They can be throwers, or flooders, depending on the distance between the LED and the Lens.

JaredM
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I personally wonder how an inverse waiver collar would perform in a reflector. Basically would be a reflective spherical shield in front of the led, covering the central say 30 degree cone that would be spill. It would work best with a shallow reflector

Pip
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Agro wrote:
You can find some experiments like that here:
https://budgetlightforum.com/node/64282

Yes, there are numerous TIR lenses like that as well.

Thanks! Some good info there. If I had the time I would like to try it with my GT90, there is so much spill that could be used, my thought was to suspend a convex lens from the front lens of the flashlight using some acrylic pipe and clear silicone glue. Basically the way the TIR combo lenses work. I’m not aware of any TIRs big enough for the GT. It would be a lot of work though because the distance from the LED to the convex lens would have to be perfect and wouldn’t be adjustable.

grin
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Im not sure it would work the outer edges of the lens would distort the beam. Glass is heavy so the mount would also obstruct the beam.

Firelight2
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I have tried installing small reflectors inside aspheric zoomies.

I also have an old Liteflux LF2XT reflector light with an appropriately sized aspheric lens.

The result:

  • In a non-zoomie, the reflector does not help. It does not actually increase throw at all because basically none of the light from the reflector is added to the spot. Instead what you get is a wide dim image of the reflector surface around the much brighter image of the emitter’s surface. I call this the “donut of doom” as it can make your beam look particularly awful on a white wall as every spec of dust and scratch on the reflector shows up in the big donut of light around the emitter image.

  • In a zoomie, adding a small reflector actually isn’t bad. It does nothing for throw mode other than adding the aforementioned donut. However, in flood mode everything is defocused and all the imperfections go away. The result is quite a pleasing beam with a wide hotspot in the center of your flood. This can make flood mode appear substantially brighter and more useful than the flood mode from other aspheric zoomies without a reflector.
CNCman
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I tried 3 different asperic lenses on lights with reflectors, the biggest at 100mm with zero success. I would not waste time on that one, sorry. Wink

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CNCman wrote:
I tried 3 different asperic lenses on lights with reflectors, the biggest at 100mm with zero success. I would not waste time on that one, sorry. Wink

Did you try suspended within the reflector or was it at the lens? I never view it as wasting my time or money, I look at it as learning. I once spent about $100 and many hours trying to disprove Earnshaws theorem. It didn’t work but I learned from it.