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You can create a pink LED by putting some fluorescent material in a blue or white LED. The problem is that some of the materials used for them are not stable, and will break down within a matter of weeks to months.

That is an interesting set of measurements, but one problem I had when I was looking at it to pick a good LED grow light was that there is no way to compare different lights because the units are not absolute; i.e. the spectra are relative to some unknown total output power. As a result, I couldn't tell if the bulge in this incadescent spectrum is more or less powerful than the bulge at the base of the spikes for this compact fluorescent light.

Now we could also get into a discussion how a spike at 440nm really is equivalent to a bulge due to the sensitivity curve of photoreceptors in our eyes...

That is an interesting set of measurements, but one problem I had when I was looking at it to pick a good LED grow light was that there is no way to compare different lights because the units are not absolute; i.e. the spectra are relative to some unknown total output power. As a result, I couldn't tell if the bulge in this incadescent spectrum is more or less powerful than the bulge at the base of the spikes for this compact fluorescent light.

Now we could also get into a discussion how a spike at 440nm really is equivalent to a bulge due to the sensitivity curve of photoreceptors in our eyes...

There are already custom LED flashlights that are brighter than any "normal" flashlight, but they are not yet what most people would consider affordable (hand-held HIDs are not "normal" and tend to be even more expensive).

Here's my current favorite, just a little bigger than my thumb and bright enough to light up the garage door of the house across the street.

http://ledmuseum.candlepower.us/second/lionhart.ht m

There are, if you can believe it, real flashlights that are almost as complicated. This one has a thirteen page user's guide in addition to a quick start guide and a reference card.

(The LED Museum is a site that all nerds should bookmark. I believe it's been Slashdotted before.)

> There is no dispute over the fact that it was an ordinary laser pointer
> involved. I'm not sure what sort of "powerful" laser pointer you have in
> mind. Go down to Best Buy and try to buy one of these "powerful" pointers.
>
> Let us presume, however, that you have somehow managed to get a "powerful"
> pointer and a monocular. You will still be unable to do anything more that
> pass the beam over the retina of a motionless man 20 feet away by "blind"
> luck, and only for a fraction of a second at a time. The feat has nothing to
> do with the power of the laser or any possible optical magnification.

I can buy a 47mW green laser pointer on ebay.
I can find a 50mW one or even a 190mW one.

Note that these class IIIb lasers that *will* damage the eye faster than the blink reflex kicks in (read: fraction of a second) on a "sweep" -- no monocular required; and can even cause damage if viewed indirectly (reflected).

being a regular viewer of candle power forums and such I've actually seen this before a while ago, as well as the laser's original manufacturer, which is here:
http://www.cnilaser.com/_private/ep_pgl3.htm

you can find a review of it here:
http://ledmuseum.candlepower.us/second/pgliii.htm

remember while this laser is a lot more powerful than a regular laser pointer it's a far cry from what a laser that's truly powerful can do. 190mW compared to a 20W Co2 laser (which is on the low side for CO2 Laser power) and the difference is quite substantial. Sure you could blind someone, but you certainly aren't going to be using it like some kind of stun gun or what not. I don't even think a Co2 laser would work that well for that.

"Hey mister, stand still! I'm trying to burn you here!"

if you wanted to do some real damage with something you could actually carry around, check this site out:

http://www.amazing1.com/burning-lasers.htm