G
On Sep 6, 1:19 pm, Dylan Smith <[email protected]> wrote:
> On 2007-09-06, [email protected] <[email protected]> wrote:
>
> > Ahh, I see now that the MR11 are HID. But at those low powers they're
> > much less efficient than LED. What they will have over LED is the
> > ability to focus into a much tighter beam.
>
> Surely that depends on the reflector and lens, rather than the bulb?
> Especially since you've got single LEDs rated at 4 watts these days.
>
Not really, High power LEDs achieve their high power rating by having
a large die area. So they don't even approximate to point sources. (I
guess one of the problems with making high power LEDs is avoiding hot
spots on the die). Therefore regardless of what lenses and reflectors
you use the beam is going to have a high(ish) divergence. (You can, of
course, create a beam with a low divergence by putting the source at
one end of a long matt black tube but you then achieve the low
divergence by throwing most of the light away.
Tim.
> On 2007-09-06, [email protected] <[email protected]> wrote:
>
> > Ahh, I see now that the MR11 are HID. But at those low powers they're
> > much less efficient than LED. What they will have over LED is the
> > ability to focus into a much tighter beam.
>
> Surely that depends on the reflector and lens, rather than the bulb?
> Especially since you've got single LEDs rated at 4 watts these days.
>
Not really, High power LEDs achieve their high power rating by having
a large die area. So they don't even approximate to point sources. (I
guess one of the problems with making high power LEDs is avoiding hot
spots on the die). Therefore regardless of what lenses and reflectors
you use the beam is going to have a high(ish) divergence. (You can, of
course, create a beam with a low divergence by putting the source at
one end of a long matt black tube but you then achieve the low
divergence by throwing most of the light away.
Tim.