Interesting optics thread

here

Here’s a very interesting LED/compound parabolic reflector setup! I think this would be a cool setup for a handheld; if you wanted a good mix of spill and throw… Can’t find a pic of the beam however.

https://www.illumi-vation.com/product-page/mooney-m20-c-d-e-f-g-j-led-landing-light

i may be out of date in my thinking here but…

car headlights, they used to have ‘fresnal’ type patterning, but it wasn’t to aid the overall throw, it was to even out the beam to get rid of dark rings and likes, or to ‘widen’ the beam, in eather case it makes the lens brighter to look at and reduces the overall throw. (bare in mind the tail end of throw is a pitiful amount, even if it reach’s the moon you wouldn’t notice it, so it would be better spent being spread into the usable beam).

the one thing i have noticed about focusing lenses is they do turn into a cinema projection, but mostly they cut out the spill, i’ve only played with a dozen or so torch’s but the one thing that was blattent was theres more throw with unlensed, e.g. i got a couple ‘throwers’ with massive focussing lenses on, now whilst i was actually impressed by the apparent throw, an el cheepo bike light with an old T-6 in it out threw them all, all be it with half a field worth of side spill. (no magnifying, just a standard non coated crappy face plate lens).

to further my thinking, i have a red led with a focusing lens i used for wild life, simply because there is next to zero side spill, quite literally a tight square led projection arriving un announced at the other end…but, again, the el cheepo dish out throws it with heck of a lot of side spill.

the reflector shape seems to have more effect.

just a thought there…at the end of the day there’s the rules of thumb, and then when you try you see it was the other thumb.

If you use math instead of rules of thumb then you can determine the performance without even physically having the components.

it depends on who’s maths. i.e. the punter maths v the real maths. google really isnt your friend lol.

edit, that wasn’t a poke at you btw. more of a sometimes you have to try even if its against the thermal laws of dynamics.(which btw is only one set of maths, and contrary to belief is not the only holy grail of truth.).

I’m not sure if I understand the setup correctly…
Is is something like this ?

I’m thinking so…

Yes, it has multiple parabola sections each with their focal point for one of the LEDs.
Basically same throw as a normal single parabola+single LED config but with more lumens.
Harder to cool the LEDs though since they stick out forward, kinda like car LED headlight bulbs.

In theory yes, but McGizmo’s beamshots looked very bad which makes me sceptical about such construction.

It’s not easy to make a shape like that.
It’s hard enough making a proper parabola for most manufacturers.

It does not appear that the LEDs are in an optimal position of focus - each parabolic section does not seem “deep” enough. He seems to have the bottom of the LED on the focal point, not the LES. That said, there’s only one beamshot in the link and it’s pointed at a stand of trees, but I don’t see anything objectionable with it…

I divide lights into 2 classes. Those where I want spill and those where I don’t.
If I want spill - it should have useful shape.

This reflector doesn’t fall into either class.

Yet another RXI optics from LPI, 25 mm this time:

Well, the thread title is Intersting Optics Thread, not beautiful beamshots against white wall… But I’ll reserve judgment until I see what something like the Illumivation light does….

I never said it was not interesting. :wink: I sure think it is.
Just that what I’ve seen doesn’t inspire my confidence that I’d like this one.

LOL yes should have inserted an emoji there. But that’s a home made thing. I would like to see the beam pattern of the Illumivation light and how it compares to the multi-reflector lights. I would think with the emitters a lot closer together it would minimize the petaling effect I’ve seen with multi-reflector lights.

you’ve been watching the you tube vids haven’t you?

whats worse than useless? an uboxing,

whats even worse than unboxing vids?

a mirrion candella flashlight beam on a house wall at ‘’wow that’s a good 30 feet away’’….or even…du dahhhhh 5 feet in the the airing cupboard lol. we need yards not feet, hundreds of them lol.

ok…if you just want to see the shape a 5 foot away wall will show the spill and spot………in a 5 foot room no less lol. my head hurts.

Looks like they’ve been defunct for a few years now. Doesn’t look like they ever brought these to the market, they look more research-oriented.
But this is interesting too - I’ve seen this (middle) style before, I assumed its purpose was to produce a floody beam, but no:


I see a russian shop hosts their datasheet:

The item doesn’t seem to be available in the shop though. So maybe they hit the market at some point…

And that last lens is indeed interesting. Though it sacrifices some frontal area. And need a windown in the front to get waterproofing (which reduces efficiency by enother 1% or so). Too bad the paper doesn’t describe it better….