Caustic Interference

[DrDissent]

Just as I suspected. Reality is way cooler than fiction.

[Mellifluous49]

I just tried to find a pitch that matches on a guitar and it does not seem to be within the Internationl A-440 12 tone equal range

[Mellifluous49]

interesting- I am hearing about 8 beats per second which oddly enough is the wave interference of the interval of a 3rd- F-A in the temperament octave in the middle of a keyboard- it breaks off random but mabe the melting randomness- how did you record this?- very interesting

[Mellifluous49]

ha ha- piano tuning is all about listening NOt to the actual tone, but rather listening to the "beats' per second or interference brtween harminic partials- the only interval tune pure "beatless" is the octave" and of course unisons- but after the temperament octave has been altered slightly to allow 12 tone equal- I have this in faves and will check it out more later- have a bit of lutherie to do first-may have to sub you-

[Mellifluous49]

faved for future study-a plucked string kepps on subdividing- F-8va-5th-4th-M3rd-m3rd-m3rd-M­2nd- some theorize sound keeps traveling and sub dividing- yes, I am a one time piano tech- vibrating strings are "phenominal" 220-440-880 works out in math but thats not what "happens" thats why a guitar must me intonated- yada yada yada...

[RoadRunnerLaser]

See??? I told you I liked interference patterns... :)

If you feel that you can put something melodious to this carcophony, feel free.

[gruadia]

What is the exact name and model of this laser? Is it very powerful?

[RoadRunnerLaser]

I cannot remember which one I was using to make this video. It was probably about 150mw of 532nm from one of my DPSS units if I remember correctly.

[gruadia]

Is it a song playing? or is it the sound that the plastic is making?

[RoadRunnerLaser]

There is no causal relationship between the audio and the video.

I simply overlaid the music on top of the video. Not sound to light and not sound FROM light.

Have I provided a meaningful answer to your question ?

[gruadia]

What is the music/song's name?

[RoadRunnerLaser]

"Caustic Interference"

[way2out2000]

great sound love it could listen all day

[ElvenDane]

WOW, cool ;-)

How about ice ? Any difference ?

[RoadRunnerLaser]

It won't melt ice but it will great some nice patterns in reflection and refraction.

Next time that I have a camera, icecubes and a laser to hand in a darkened area I will make sure to record some video.

[minichuaman]

would you mind explaining this video to me?

[RoadRunnerLaser]

The visual effect is caused by using a high powered laser to melt a piece of plastic. As the plastic deforms, it causes the light to reflect off in a non-uniform way. As the reflected light is no longer a nice parallel-sided beam, the light produces interference patterns and caustic reflections.

(A caustic reflection is what you see when you look at that bright "W" in the top of a tea-cup). Interference patterns occur in COHERENT wave sources when overlayed.

Wiki will give more info on both.

[RoadRunnerLaser]

Search: "Interference patterns" or "interferometry" and "Caustic Reflections" and this will explain all the mechanisms behind the visual element of this video.

The audio, if you hadn't already realised, is from my EWI and was dubbed on later prior to upload.

By the way... Just in case the thought has crossed your mind... The EWI is not the source of the aliens in my "alien voices" video. However, my wireless stage audio system works on.... 864.5Mhz.

[paintballingjoe101]

Thats pretty cool even though I can't even tell whats going on.

[RoadRunnerLaser]

It was recorded in the dark. All that is visible is the interference pattern in laser-light captured on a wall. The laser is being reflected from a piece of plastic as it melts. Neither the laser, the beam, nor the plastic (a pen) are visible in the shot.

If you want to know WHY it's creating patterns, you should research 'constructive and destructive interference in wavefronts'.

[LlamaZama]

what ever the hell just happened... it was cool.. lol

[RoadRunnerLaser]

Hehehe... Thanks...

You were looking at a laser being reflected off a tiny pool of molten plastic. The laser was melting the black plastic. The deformations in the surface of that plastic were causing interference patterns in the reflected light. To complete the effect, I played my EWI and recorded some music to go with the video.

[icetrout]

nice.

[RoadRunnerLaser]

Thanks. :)

[RoadRunnerLaser]

I like that. Nice use of a laser and music.

You could also put a container of water on the speaker and reflect the laser from the ripples on the water.

I wouldn't recommend doing that to your best speakers though !

[majorvoltage]

That's cool. It reminds me of an experiment I did with a laser once. I connected a water droplet to a speaker and played music on it, then shone a laser through the droplet onto a piece of paper. As the droplet changed shape with different modes of vibration, it changed the patterns of the diffused laser beam. So I got this weird light entity that danced to the music. It was cool.