Interesting optics thread

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….

Here

Wow, thanks for the link.

I remember seeing LL datasheets before but never got interested in their lenses. But they seem to have many ultra-compact lenses available:
https://www.ledlink-optics.com/wp-content/uploads/2018/05/2018-Commercial-Lighting.pdf

For example:
LL01CR-CTKxxL02-P is 49.5 x 7.8 mm designed to produce narrow (10 degree) beam with 3535 LEDs. Can’t find a datasheet for it though.
21700 thrower with 52 mm head and 100 mm length?

Or V-Cut LL01CR-DAWxxL52, smooth beam thrower lens (how does it compare to OP?), 45 x 10.85 mm.

Looking for a source for lens type optics for large COBs (over 22mm dia. LES). Aside from reflectors, everything I see is for 19mm and under.

@Agro
You have to replace “xx” in the part number with the angle, in this case 10, then you (or google) will find it —> https://www.ledlink-optics.com/upload/product2led_light/23_120180531033432.pdf

You can have a look at the LPI patents if you want the gory details. Or this, it’s a bit easier to read. I have also found their book “Nonimaging Optics”, very interesting but so complex that I can’t even scratch the surface.
Looks like these things were a bit of a byproduct of researching solar concentrators for multi-junction cells.

I’ve always been partial to Ledil lenses since they had numerous choices for 35mm optics for single or multiple LEDs. The Cute-3 S and GT4-XP-S paired nicely with 32mm triple and quad mcocb’s.

Or soda can thrower with 52 mm head and 90 mm length? :slight_smile:

I tried that but failed to find anything. Thanks!
Key takeaways:

  • LED opening is 7.54 mm so basically any LED, even XHP70.2 should fit (XHP70.2 diagonal is larger but only the dome enters the lens cavity).
  • The bottom is patterned, so it’s not a pure throw design, they do some beam mixing as well
  • That’s a Fresnel TIR at a portion of the bottom :slight_smile:
  • Flat round front, nothing that would make mounting harder
  • They list it as high efficiency but fail to provide any efficiency numbers (except for the raw plastic that they use (polycarbonate))
  • Performance is specified only for some COB so I won’t predict how well it collimates.
  • Beam shape: spot with barely any spill. Looks very good to me.

I’ve seen that pdf before. But not the book. $20 for a pdf. With such non-recommendation I’ll skip it for now but maybe one day…. :slight_smile:

LedLink:
LL01ED-ASAxxL06-P, LL01CT-APGxxL06-M2 are up to 26.5
LL01ED-ABXxxL06, LL01CR-BAYxxL06 are up to 24.2

I intended to write about Fresnelized TIRs for a while…

A simple TIR lens guides light on 2 paths:
The light emitted forward is refracted as it enters the lens and again as it leaves it.
The light emitted sideways is refracted, TIR-reflected and refracted again.

It is possible to fold one or more surfaces to reduce height. Some call this TIR-R, some Fresnel-TIRs.

Here’s a one-time folded Kingbrite KB-H43-3-XP

Four-time folded Ilenstech ILENS508-COB90-10-H

You don’t have to fold the sides, you can fold the front instead like Ilenstech ILENS576-COB69-12-H

Or you can fold the back like Darkoo DK4304-XP-G

Here’s a good paper that generalizes the concept:
https://www.orafol.com/tl_files/EnergyUSA/papers/LED-Source-Modeling-for-Optical-Design-workbook_Davis_2004.pdf
And some more papers / articles:

Note that Ledil makes Fresnel TIRs too:
https://www.ledil.com/product-landing/single-lenses/OLIVIA/

I think I’ve seen some Led Lenser that had the outer front folded though I can’t find it now.