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Pretty much what happened in that shirt, maybe lasting a little longer. Flourescence is where high energy photons excite atoms or mollecules to an excited state, which then drop down to a slightly lower state, then drop back down to the ground state, emmitting a photon of lower energy (longer...

The idea of using a laser as a source of force is not new, with the most recent case i can recall being: http://www.baeinstitute.com/pr1.html Basicly, light has momentum but it is so small that you don't fly out of a room every time you switch on a light bulb. In fact, even when using weopens...

I think the act of blasting away the paper creates sound itself which is why you hear the 1000 Hz. I don't think it would transfer that much energy to the paper to act as a speaker.

Yep, Power is measured as Energy/Time. If you take the same energy, and decrease the time that it is contained in, then you increase the power. That is what the Ti:Sapphire laser does. It pulses the light so that all the energy is compressed into a thousand 120 femtosecond pulses. You can use...

Just thought I would show you a video of one of the lasers I get to work with at the Australian National University. It's a Titanium:Sapphire laser pumping out a thousand 120 femtosecond pulses of 800 nm light a second. Each pulse contains about 500 uJ of energy, giving a peak power of about 5...

First off, power is measured in Watts, or Energy per Unit Time. 1 Watt is classed as 1 Joule of energy over 1 Second. If you compress that 1 Joule down so it lasts 1 nanosecond, then your power jumps to 1 Billion Watts. The trick is that this power only lasts for that 1ns making the average...

Yeah, not advisable really, high chance some poor person could catch it in the eye. Not like you would be able to see it easily either. Keep it to LEDs :)

Batteries drop their voltage with increasing use and show that pulse effect when they are starting to run low. Happens with ordinary torches as well, just a property of batteries. Green lasers use a nonlinear crystal to double the frequency of an IR laser to make it green. To achieve this effect...

Re: mW or nm  - Which factor counts most for Shorter wavelengths have more photon energy, so a certain number of blue photons will be more powerfull than the same number of red photons. In reality though, this difference is quite small when you tap it on the end of a bazillion photons that are...

"Hey Quagmire... isn't Country spelt with an O?" Tallaxo, the graphs are for perfect 'blackbodies' that absorb all radiation that fall on them. It means that the emission is only dependant on temperature and not other effects like the electron transitions of atoms. Think of it as a giant...

Blackbody Radiation The Sun and our position relative to it is quite possibly the single most important asset the human race has, and ever will, have. It provides a source of gravity that lockes our planet in the 'goldilocks zone' and provides energy, that in the goldilocks zone, is perfect to...

Am I the only one that notices "Simulated Laser Beam Because photographing a REAL laser beam in very, very, very difficult." written below the images?

Goto Australia :) Melbourne - http://www.swin.edu.au/feis/photonics/ One of the things we have done: Turning this: http://www.progsoc.org/~wildfire/aum/images/opera-house-in-afternoon.jpg Into this: http://pubs.acs.org/cen/images/8231/8231operahouse.jpg The first is serveral stories tall...

Oh man its a shame the mirrors are pre set! We had a student system at uni where we had to put our own mirrors on it. You really, really have an appreciation of what it takes to get a laser to lase. You could even have it run at 01 modes as well if you inserted something like a pin in the...

Water absorbs at 1400nm so if you had that wavelength it might make it easier to heat it up without damage. The problem that making a laser at that wavelength is pretty useless for any practical purpous due to the absorbtion of water which can be found in pretty much everything. In general, IR...

Basicly, it is a sophisticated current and temperature regulator. In the scientific world at least, many experiments require precise intensity and wavelength. Any variation in current and temperature has the potential to effect both, particularly the wavelength. I worked on a few experiments...

The Australian/New Zealand standard has had 1M, 2M and 3R for a while now. The Ms simply mean that you should not view the beam with magnifying optics. The 3R in Australia at least replaces 3A. Not sure why the letter change, but the basics are the same. Class 1: All wavelengths safe for eye...

h t t p : / / news.ninemsn.com.au/img/sport/afl/1408_johnsonlaser_sp.jpg From an Australian Rules Football game last week. Two players were targeted with a green laser pointer. The league is putting plans in motion to fine people $5000-7000 AUD for using a laser at any future game.

Well, if you take a laser beam (coherent light) and pass it through two very narrow slits that are reasonably close together then the light exiting the slit will act like two coherent sources of light and their waves will interfere to produce a pattern called an interference pattern. This is...

Bah, first of all (not to you), someone tell the moderators to turn the no link posting shit off! Third time I have had to rewrite a post because this forum software REFUSES to let me remove the links from the post I made. It just deletes it. Half an hours typing gone. Thank out non existant God...