06-07-2024, 04:34 PM
I guess carbon arc was before filament lamps.
Oil lamps originally.
I think also they use a kind of Fresnel lens. A larger LED array would be problematical for creating a beam no matter what kind of lens. Hence LED torches have gone to single LEDs now, or what looks like a single LED so a suitable beam (or even "zoom") is possible. Multiple wider spaced LEDs would need an insect style set of lenses.
Oil lamps originally.
I think also they use a kind of Fresnel lens. A larger LED array would be problematical for creating a beam no matter what kind of lens. Hence LED torches have gone to single LEDs now, or what looks like a single LED so a suitable beam (or even "zoom") is possible. Multiple wider spaced LEDs would need an insect style set of lenses.
