Alarmclock puzzle
Robin Paulson
robin.paulson at gmail.com
Wed May 14 09:28:37 CEST 2008
2008/5/14 Sven Klomp <sven at klomp.de>:
> I had the same idea and bought two 1W LEDs. I can dim them with PWM from a
> microcontroller. The microcontroller has its own power supply and will be
> connected via USB to the Freerunner. Thus, the Freerunner can control the
> LEDs in the morning and is also charged during the night (I belive the
> Freerunner can be charged in host mode).
>
> Maybe I don't need a wake-up sound since the LEDs are VERY bright :-)
yes, that would all work, but it reduces the neo to a bit-part in the
process - i might as well have a separate alarm clock if i have to
faff about with external components in that way.
maybe if the neo itself could do the pwm, hacking a couple of leds
into a modified case would not be so difficult?
on the wiki i see the neo screen can emit 220 cd/m^2
which is ~0.0819 lumens (guessing at a 25deg cone for the light emittance)
and from this http://en.wikipedia.org/wiki/Lumen_%28unit%29 ,
a 100W incandescent bulb emits about 1700lumens
=>a 12W bulb (as in the soleil alarm clock) emits about 200 lumens
a lot more than the neo screen, so i guess i'm out of luck
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