My W30 fell apart

[quote=grin]

Yep exactly that!, phosphorus doesn’t reflect it just converts energy to luminescence.

I don’t think so. LEP is a Lambertian emitter (much like a LED) and light is scattered in all directions. I just checked it up…
So the beam needs to be narrowed down rather than widened.

While making sure that the emission is Lambertian I stumbled upon a patent for a RLT collar on a LEP. :person_facepalming:

When a layman (like me) can come up with an invention by themselves, it shall not be patentable. But reality shows otherwise.

Oooo well in that case you could massively improve performance :smiling_imp:

it really sucks how they have tied up those collars so no one can use them, they have so many applications and i mean really they could be making a fortune selling them as an upgrade

There greed will backfire because sooner or later the chinese will rip it off and they will have missed out on all of those sales (rant over)

When a layman (like me) can come up with an invention by themselves, it shall not be patentable. But reality shows otherwise.
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Yeah now i will call it Light Recycling Reflector. Today I was talking to a fitter about machining them out of brass and electroplating the inside.

The problem with making them is they need to be Retro reflective , not reflective

I have a hunch the patented ones use the refraction of the glass to adjust the reflected beams angle

They pretty much just make the mirror spherical.

Then any reflection from the focal point goes right back into that point. LEDs and LEPs are not point sources but they mostly symmetrical and an off-axis reflection just hits the opposite side of the emitter.

look at this in reverse with your emitter at the focal point

Bit of interesting info here stars from the paddock

Well the parabolic version could well be doable… Im still not convinced on the hemispherical one maybe im just being thick here I cant see why they would choose a difficult costly material like glass unless it was needed , and the only reason iv got is refraction ? my understanding is that curving the mirror does not change the angle of reflection , it would still be reflective not retro reflective , having it spherical will however correct for the divergence and refocus the reflected beam

“Seems my W30 fell apart…”

The W30 is marketed as a dive light (claimed 100m water resistance), and it just “fell apart?” That doesn’t give me much faith in their water resistance claims.

I think it had help….

No, they are simply reflective, not retroreflective

But that doesn’t work on the hemispherical design

Only the parabolic version can work with reflection alone

This “concave mirror” is parabolic not spherical.
With a spherical mirror, rays coming from outside wouldn’t focus on a single spot. But ones originating from the focal point would go right back where they started. That’s because regardless of where they land on the mirror, they would be orthogonal to the mirror’s tangent plane at that point. That orthogonality is literally the definition of a sphere….and light rays hitting a mirror orthogonally are reflected right back.

ADDED:
I think the misunderstanding might be the focus on rays that exit the mirror.
With a full, properly positioned hemisphere there should be none.
Reflective collars work because the hemisphere has a cutout (typically right in the middle) through which light can escape towards the lens.
See the marinebeam drawings.

BLF: Curious enough to void the warranty, Smart enough to obey the warning labels.

Aha, Thank you I stand corrected.

So hang on then if that’s how it works why dont we just paint the dome of the emitter with mirror paint and slice the very top off?

So hang on then if that’s how it works why dont we just paint the dome of the emitter with mirror paint and slice the very top off?
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I think this has already done. Just a matter of finding it.
I have reinvented the wheel more than once.

Old djozz experiment:

Some more discussion from a later reinvention:

5 years ago :person_facepalming: guess im still back of the class

Dont panic there is tonnes of info here just have to find it.