I'm building a sort of "ultimate" handheld thrower right now, and I've just looked and Enderman's top 50 list of throwers, and I noticed many aren't using the typical reflector and flat lens setup. I also noticed there are many lenses (aspheric, spheric, fresnel, convex, etc.) and many aren't described well enough for the typical noob like me. My question is, which lense is best for long range and would people be able to give me a definition of each lens and it's use for future reference?
Aspheric is what you want for throw, because it makes the tightest beam.
Spherical does not work well because it does not have one common focal length, which means not all of the light from the LED can be concentrated into the hotspot.
Fresnel lenses come in both spherical and aspherical options, but these are only used if you need something of very large diameter (like 12”+) because of their lightweight design compared to a solid lens.
They perform worse than a single surface (aka normal) aspheric or spherical lens, so basically don’t use them at all for flashlights.
Convex is the surface of the lens, what you want is plano-convex which means one side is flat and the other is curved out.
Unless it says concave, you can assume your lens is convex.
You cannot use concave lenses to focus light.
Thank you. If I were to use an aspheric, would I still use a reflector or are aspheric lenses only used in zoomies? Also, do aspherics have some sort of focal point or do they just spread out the farther they go like a regular reflector light does? I've seen a couple beamshots of zoomies where it looks like the beam sort of focuses a few feet from the head of the light, which makes me question whether it really throws any further than a reflector light does.
When you use as aspheric it replaces the reflector.
You don’t use both.
The light from an aspheric spreads out a lot less.
If the beam looks like it is focused in front of the flashlight then that means it’s not focused properly, for best throw it should go in an almost perfectly straight line.
The throw will depend on the intensity of the LED and the diameter of the lens. Not how tight the beam is.
- Thanks. Also, are Fraen Nested Lenses used in flashlights? I don't think I've seen a light with it yet but it is the one lense I do know a bit about and it never seems to be talked about anywhere.
TIR lenses are definitely used in flashlights, but they don’t give the best throw.
Are TIRs and Fraen Nested Lenses the same thing? Maybe their advertising is tricking me but I came across an image showing the differences between the two, and it shows the Fraen putting alot more light in the right direction. I haven' figured out how to upload an image yet so I can't show you yet.
Yeah they are just a different design TIR.
Maybe better than normal TIRs, idk, but it’s not possible for it to be better than a single aspheric lens of the same diameter. (for throw)
It will probably be better for luminous efficiency though, as TIRs usually are.
In a fixed focus light, would an aspheric lense go further than a reflector or are they about the same? I'm also looking at the Wavien RLT thing that I saw on one of the lights of your list, do you know anything about that?
The wavien collar increases intensity by about 2.2x which is the main reason to use a lens over a reflector.
It cannot be used with a normal forward-facing flashlight reflector.
Without the collar, a lens will not perform significantly better than a reflector, since the front area will be almost the same. (comparing based on same diameter)
In this case the main difference will be that the reflector light has spill while the aspheric one does not.
Thanks for the clarification. So from my understanding, the Wavien collar is to be used with an aspheric lens?
Yeah, if you can manage to get one.
Thanks alot
