Optic comparison - Polymer Optics vs Ledil

Okay, I have put some pictures up that have been a "long time coming" on my website:
http://christexan.com/Biking/bikelights/LensComparisons/index.html
It's not much, but I've been waiting for awhile for someone (anyone) to actually compare the Polymer Optics brand optics for the Cree XR-Es to any other optics. Nothing has appeared in the past few months (well, I started looking in Jan/Feb timeframe). If anyone wants to link to those photos and put them "inline" here, you are welcome to, I didn't feel like messing with it, it's a single webpage that gets the point across quickly.

Okay, my conclusions in a nutshell, the 6-degree seems great (as does everyone's 6-degree), however the 25-degree Polymer Optics is trounced by both the Ledil and the Fraen 25-degree models. It is full of artifacts (no surprise, it's not diffused), but more importantly, without diffusion, it appears less bright than the diffused Ledils and Fraens! I could be wrong, I don't have a lightbox, but to my eye, and in the photos, it just doesn't compare, maybe it's the dark artifacts throwing me off, but it appears there is a lot of light being lost in the geometry (leading to the dark "square" where you would expect a solid wash of light just off center). I tested 3 different ones, so it's not a bad lens (I had to reseat one in the "holder" they are just a press fit, so they require some sort of cover to secure them besides the holder, I emailed Polymer Optics twice now (different issues), the last time regarding whether the flats could be used to apply silicon to secure the lens in place without substantial light loss <edit> and have received a response on the last issue, that there would be some light loss on the machined edges, but essentially, they aren't the best reflective surfaces to begin with due to their machining process (their words), so it wouldn't be a large amount.
Anyhow, they are tiny, the hexagonal pattern makes great packing density (they match the "MR-11 triple lens" format used by Khatod exactly, but without the extra "ring" of material to fill out the MR-11 circle), 3 fit in roughly the same area as a Ledil lens, but the 25-degree is losing light somewhere. The 6-degree is great, appears about the same as a Carclo or Ledil 6-degree optic (basically a concentrated image of the LED die itself, only bigger).
Hope that helps someone out there considering these lenses, again it's not a "1-off" test, I tested several samples and verified proper seating etc, and the 25-degrees just don't compare to others out there.
For what it's worth, I've tested optics from Khatod, Fraen, Ledil, Carclo, and Polymer Optics so far, the Fraens are nice but have a slight "6-point star" pattern in the 25-degree model, it's not distracting though in usage, more interesting as a curiousity than anything when "white wall hunting".

Thanks for those comparisons! They were very helpful. I was thinking about some future projects, and they would require an array of LED emitters and optics. At first, I liked the 6 degree Polymer Optics small hexagonal optics because of their small size and their ability to cluster together cleanly. Then, I worried about their size and how well they performed to the standard 17mm or 20mm TIR optic. I thought that they had a lower lux/lm optical efficiency. Fortunately, seeing it compared to a larger Ledil optic (of better quality and from Italy -if that matters), I was amazed. Will you post more pictures comparing the PO 6 and 25 degree optics to Fraen or Carlco 6 and 25 degree optics, perhaps?

It would be really cool if you can make a small review of the optics, possibly ranking them in terms of brightness, beam shape (angle? hotspot?), quality, and size. You would be one of the few, I think. I was browsing for the best "narrow" optic, and I would like to see what is the best there is, while still being compact enough to be very useful in very small, as well as very big, multi-emitter projects. I appreciate what you have done. You benefited bikers, cavers, and general flashaholics alike. I hope to see more of your useful information...


-Tony

I have an order coming in with samples of Ledil and Polymer Optics for Cree XREs. I'll see if I notice the same issues with the Polymer Optics.

Update: I did receive a response to my last email about sealing the top edges (on the flats) of the optics from PO, updated the first post to reflect that.

Regarding more testing, I will do so as I have more time, it probably won't come for a few weeks though at best, most of the optics I've used are "installed" already in sealed units, the only loose ones I currently have are the ones pictured (I have more of the same ones loose, but my Fraen and Carclo units are in use elsewhere, so I can't do an apples-to-apples due to different driver currents, etc).

Glad to help, I figured since I was looking for it, others likely were also. There are more shots than the posted ones, just picked some representative samples. I'm planning a fairly sophisticated bike light setup for these, if it works more details will come in the near future, and if I try any others I'll pass along shots as I get them, I usually remember the next day after the silicone has set "oh crud, forgot to take beamshots with different lenses".
The LED used was my last P4, my "test bench" model, it will find a permanent home on a good heatsink so I can do testing a bit more easily (it's literally perched on top of leads soldered to the bottom contacts at the moment). Since I've switched to Q2s and I'll move to Q4/5s as they come down in price, it's getting orphaned to test duties.