Surefire U2 Pyrex window question

precisionworks

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The search function didn't bring up anything about this ... the Pyrex window on my new-last-week U2 has a curved outer surface. I'd call it a meniscus or diopter lens, which somewhat explains the wide spillbeam. Any links to other posts on this?

TIA.
 

DaFABRICATA

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Its just a domed "window" as Surefire calls it.

The spill is probably just due to the reflector



1000......beeeeeeyotch!
 
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greenLED

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Lux V's pack 4 LED dies on a single surface and emit a broad beam by default.

If anything, the deep reflector and the domed window (it's not a solid diopter lens) help focus the beam somewhat.


DeFab sneeks a post while I was typing...
1000......beeeeeeyotch!
Call me when you break the 10000 :nana:
 

adamlau

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Helps provide for a wider field of view. Examine your reflection from the back of a round spoon and you will see what I mean.
 

precisionworks

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I do appreciate the responses, and it makes sense that the reflector + lens combination are designed to give the beam the characteristics desired by the manufacturer. There's a dramatic difference in the E2L beam (spotlight) and the L4 (floodlight) and the U2 (floodlight with wider spillbeam).

Do any other Surefires use the curved lens?
 

Lightingguy321

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The older model KL1 (used on E1L, E2L), the old X200A, the KL3 (2nd Gen), the older (luxeon III) L1, the L5, the L6, and the L7. They all used domed Pyrex windows (apparently the E2D also has a domed window)
 

Ty_Bower

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I had been led to believe the curvature of the Pyrex window on the U2 was only for structural integrity, and had little or no impact on the distribution of light.
 

Clifton Arnold

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As to your integity claim! I had to send my U-2 back in because the Lens had broken in half. Surefire has had it for 6 weeks at this time. They have been waiting for replacement Lenses. I really miss my U-2 I use it as EDC.
But Surefire stands behind their stuff REALLY WELL.
 

cbxer55

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I use mine as an EDC as well. I have had mine since Jan. 2006 and have not had one problem with it. Love the beam pattern, more so than the Fenix P1D-CE I also EDC.
What would cause your lens to crack?
icon_scratchhead.GIF
 

mcmc

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Don't forget, the Kroma also has this.

And I also suspect it is more for protection, than optical usage.
 
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