Nereus
Enlightened
There have been a lot of discussion about the Fenix P1D CE beam in the CPF. Many of us see a ring around the hotspot. Please have a look on the Cree XR-E datasheet: http://www.cree.com/products/pdf/XLamp7090XR-E.pdf , especially the page 5 "typical spatial radiation pattern". There are small but visible peaks on both tails of the light distribution, some 85 degrees off-axis. These peaks are small compared to 0 degrees peak lux but very large compared to the close proximity brightness around 85 degrees off-axis. When going from 75 deg to 85 deg the increase in the (relative) intensity is more than 100%. And since this small peak is so much off-axis it hits certainly the reflector. And since the smooth reflector seems to (in my opinion) be close to parabola the "minor-peak" (is this a proper english word?) light will be projected almost parallel to axis. As a result, in white wall beamshots this portion of light ends up in the close proximity of the hotspot.
After this reasoning I have a question open to CPF discussion: could the P1D CE beam ring be a reflection of this off-axis peak?
-N
After this reasoning I have a question open to CPF discussion: could the P1D CE beam ring be a reflection of this off-axis peak?
-N
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