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Subject: Re: [Homebrew_PCBs] Re: Small Quntities of Dry Film Resist (UV LEDs)

From: Russell Shaw <rjshaw@...>
Date: 2008-01-28

Adam Seychell wrote:
> I just realized potential confusion about LED angle specifications. Is
> "20 degree" LED a 20 degree from centre (or +-20 degree) or the total
> conical span (+-10 degree) ?

Usually it means +/-10deg between 3dB points. The LEDs on ebay commonly
show the radiation polar plot.

> In any case a 8 degree LED will have much higher mcd rating than 20
> degree due to the difference in light concentration.