Note that power level is 5 mW.
Typical white LED at 20 mA is about 60 mW.
Fun and almost useful, but not bright.

Very best LEDs give 200 l/W so about 1 lumen.
Sheet of A5 is 1/32 m^2 so if you can get half of light evenly over an A5
sheet =3D 16 lux.
That is good enough for monochrome text and marginal for colour. Hold it
closer :-).

She uses 3 x LEDs in parallel - presumably helps further drop V_LED.
Many White LEDs will be badly colour shifted at such low powers.



            Russell




               R


On 4 July 2013 02:20, Tamas Rudnai <tamas.rudnai@gmail.com> wrote:

> Sounds really interesting!
>
>
> http://ca.news.yahoo.com/blogs/geekquinox/b-c-teenager-hollow-flashlight-=
takes-her-google-185546413.html
>
> Here is another video:
> http://www.youtube.com/watch?v=3D9CCGUMkcbjg
>
> Tamas
> --
> int main() { char *a,*s,*q; printf(s=3D"int main() { char *a,*s,*q;
> printf(s=3D%s%s%s, q=3D%s%s%s%s,s,q,q,a=3D%s%s%s%s,q,q,q,a,a,q); }",
> q=3D"\"",s,q,q,a=3D"\\",q,q,q,a,a,q); }
> --
> http://www.piclist.com/techref/piclist PIC/SX FAQ & list archive
> View/change your membership options at
> http://mailman.mit.edu/mailman/listinfo/piclist
>
--=20
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