Femtosecond Lasers Used To Color Metals

Maximum Prophet writes "An optics professor and a postgrad have developed a way to use ultra-short pulses of laser light to etch nano features into the surface of metals so that they can absorb or reflect specific wavelengths of light. This is very similar to the way that butterflies get the color in their wings."

WOW!

[JoshEanes (1172285)]

wow, butterflies use high energy lasers to get the color on their wings!?!? now, we have to worry about lasers in the hands of the insects...

Re:WOW!

[jollyreaper (513215)]

wow, butterflies use high energy lasers to get the color on their wings!?!?

Not to self: don't fuck with butterflies.

Re:

[sm62704 (957197)]

"This is very similar to the way that butterflies get the color in their wings."

It's even more similar to the way CDs have rainbows on them.

taste the rainbow

[davidwr (791652)]

I ate a CD once. It tasted nothing like Skittles.

Muhammed Ali vs the CD

[sm62704 (957197)]

tastes like a rainbow, stings like a bee

New upgrades to "Shark Army(tm)" project

[DrYak (748999)]

wow, butterflies use high energy lasers to get the color on their wings!?!?

Forget the sharks !
Let's make an army of butterflies with freakin' femto lasers on their head and take over the world with them.

Re:WOW!

[Rei (128717)]

Why did you link an article that argued against your point? The article says that the bright color of the upper sides of the wings is due to interference, and that only the dull underside is due to pigments.

Most of the colors in my parrot are due to the same diffraction effect from the spacing of the barbs in his feathers. There are two interesting things you can observe. One, when you get him thoroughly soaked in a shower, he becomes all dull except for the yellow feathers on his head (which are pigmented); it's a pretty dramatic color change. Two, when the tips of a feather passes in front of another feather, you get neat Moire patterns.

Re:

[BytePusher (209961)]

I don't know about your butterflies, but my butterfly emits light! Take that you insensitive clod!

Re:WOW!

[Rei (128717)]

[quote]Color has exactly one definition: the particular hue, not the intensity thereof. The color is determined by the color of the powdery scales.[/quote]

The article says nothing of the sort. In fact, it says just the opposite: "Blue light has a wavelength range from 400-480 nm, and is the only wavelength that is interfered with constructively by the slits of the morpho, which are 200 nm apart."

Your article completely undercuts your argument.

uh huh...

[r00t (33219)]

Sure. Your "shoulder" or "arm". Riiiigh...

  <0)
  ( \
   X
8====D

Not that there's anything wrong with owning a p3n15 b1rd.

Re:WOW!

[Zymergy (803632)]

There is some confusion here, Please first refer to this: http://en.wikipedia.org/wiki/Additive_color [wikipedia.org] and to this http://en.wikipedia.org/wiki/Interference_filter [wikipedia.org]
Actually, butterfly wing-scales are the color of the underlying wing cells that produce the scales (and not blue, etc..) The scales are actually not blue, they are probably the color of butterfly skin cells.
The intense powder blue colors observed in butterfly scales are caused by Optical Interference Filter phenomenons in the microscopic slits in the surface of the scales *only* and not from a pigment or dye. Think of it as a mirror that adsorbs light in all optical wavelengths and reflects only the shades of blue observed. If you were to shine light of different wavelengths like pure green or red, the wings would be appear dark or mostly black as they absorb wavelengths of light that are not those specific to those shades of blue light they reflect.
Traditional colors (in most things we see daily) are caused by pigments and dyes (subtractive color) or from CRT/LCD/Plasma display RGB techniques (additive color).
This 'new' technology using "Femtosecond Lasers" creates precise cuts in the surface of metals (or other substances), to create these precise interference pattern slits to produce brilliant colors. These slits act as a slit interference light reflector/absorber as they brightly reflect specific wavelengths like a selective mirror and adsorb others. This method is vastly more efficient than colored subtractive filters and therefore produce colors far more intense than any pigment or dye could produce.
All butterfly and moth scales are made of non-living insect cuticle. Insect cuticle comes from epithelial cells and is made up of chitin and protein. These Chitins and Proteins are not necessarily colored or pigmented. Their observed 'colors' virtually all come from their nano-scale *structures* which have microscopic optical interference reflectors/absorbers. Some insects use these 'scales' to very efficiently absorb light to stay warm in sunlight and the light reflected is very brilliant and is essentially a mirror to particular wavelengths.

The important thing FTA is that now mankind has learned how to use lasers to be able to modify the surface of metal substrates (of whatever native 'color') to adsorb and reflect specific wavelengths of light in the visual range. This can be used to make better coatings and even better camouflage. The USAF already uses similar technology in their "stealth paint" with radar-adsorbing interference filtering "stuff" in the paint itself (as well as the shape). This new technology reads to me to to be a good step in the direction of daylight stealth and camouflage, but just like the butterfly wings. Once touched or structurally affected, the surface structure changes and so does the color absorption/reflection. This is why it is very necessary to carefully clean stealth aircraft just before missions, otherwise combustion particles, dust, etc.. can reflect radar and defeat some of the paint's stealth properties. This would have a similar optical effect on the "Femtosecond Laser-colored Metals" referred FTA.

Re:

[ozbird (127571)]

I think you meant to link to the diffraction grating [wikipedia.org] article.
Diffraction gratings using parallel lines to produce the colours; interference filters using layers of differing refractive indices.

Hmm good bye automotive paint??

[moogied (1175879)]

Perhaps the end to automotive paint?? Just throw clear coat over the chagned metal...

Re:

[somersault (912633)]

yep I'm sure going over the car with a laser scalpel will be much cheaper than using paint!

Re:Hmm good bye automotive paint??

[psbrogna (611644)]

It might be cheaper given the cost of disposing of hazardous waste associated with conventional painting processes.

Re:

[JeepFanatic (993244)]

I could see this for high end vehicles where people would be willing to pay the premium for a car who's "paint" will never fade.

Re:

[Sandor at the Zoo (98013)]

Once you have the equipment, it just takes electricity. No need to buy paint, dyes, etc. on an ongoing basis. And according to the article, it's part of the metal, so it doesn't flake or rub off.

Re:

[djlemma (1053860)]

I have to wonder how difficult it would be to rub off the outer layer of the metal that's causing the wavelength modifications.. The article implies that the laser is modifying the metal at an atomic level, and I can't imagine it'd be too tough to scrape a few atoms off the surface of an aluminum body panel. What happens when a bird poops on the hood of your laser-colored car? Or worse, when some road tar gets splattered onto your front bumper. Normally, cleaning these up involves solvents and scrubbing,

Re:

[orclevegam (940336)]

Yeah, it would be vulnerable to scratching and wear, but if you put a clearcoat over it as some have mentioned, and made sure to wax it like you would any other car (or at the bare minimum scrub it down really well every 10 years or so and put a fresh layer of clearcoat on it) you probably wouldn't have to worry about the actual metal being damaged.
I really don't see it being much of an advantage over regular paint in most cases, but it's a cool technology to have anyway and we may find something it's real

Re:

[jank1887 (815982)]

The problem is that where a paint coating of measurable thickness will take a certain amount of time to wear once direct exposure sets in, the super thin modified metal layer will only take an extremely short time to wear away. You'd have to be careful when waxing the car to apply very gently.

Re:

[onion2k (203094)]

Automotive paint isn't just used to make your car look pretty - it's also a protective coating to stop it going rusty.

Re:

[Hoi Polloi (522990)]

I wonder how rugged this etching is. Even though it is burned right into the surface of the metal it still is a very thin layer. How resistant to corrosion and wear could it be?

I, for one

[Malevolent Tester (1201209)]

Welcome our new femtosecond laser wielding butterfly overlords.

Neat!

[Rizzen (1059004)]

As an artist I find this highly interesting. I'm always looking for new mediums to work with, and I certainly hope this becomes easy enough to work with where I can experiment with it. I'm sure it would open up a whole host of new ideas for creative avenues.

I've got to call bulls**t

[DoofusOfDeath (636671)]

An optics professor and a postgrad have developed a way to use ultra-short pulses of laser light to etch nano features into the surface of metals so that they can absorb or reflect specific wavelengths of light. This is very similar to the way that butterflies get the color in their wings.

There's no way in hell a butterfly has the discipline to set still while being laser-etched.

Oblig. XKCD

[by Anonymous Coward]

What a coincidence http://www.xkcd.com/378/ [xkcd.com]

Sure it was the butterfly

[techpawn (969834)]

No one EVER suspects the butterfly...

A novel way to mark items for identification.

[TheLazySci-FiAuthor (1089561)]

I wonder if this will work outside the range of visible light: up into ultraviolet or down to infrared wavelengths.

It might be a novel way to unobtrusively mark equipment or vehicles with permanent serial numbers or some kind of identification method for recognition by, say, machine vision, but which would not be visible to the unaided eye.

For robots to begin work in our everyday world, I feel that at first they are going to need some special markers around the house and office to help them recognize important objects more easily - this could be a very efficient and elegant way to accomplish just that.

Re:

[DerekLyons (302214)]

It should work in a variety of wavelengths. For 'house and office' use however, it boils down to two question: 1) how many common materials will take the markings (looking around my house and office, I see little metal and most of that is painted*), and 2) will the marking remain visible under a layer of dust (within a few hours of cleaning, you'll start to accumulate more - even if won't be visible to the naked eye for a day or two)?

*And how well a given metal accepts these markings will depend heavily o

Colour me cynical

[GauteL (29207)]

.. but when I see things like "professor and a postgrad have developed", I assume that the postgrad did all the work and the professor took most of the credit.

Re:

[aprilsound (412645)]

I assume that the postgrad did all the work and the professor took most of the credit.

That's a given. Tenured professors exist only to lend their fame to important work done by postgrads and graduate students. Oh, and raise the money to do it. I'm only half kidding.

Re:

[fishybell (516991)]

I asked by dad, a tenured professor / associate dean at the local university, and he said it depends on the professor. Most professors, and all the good ones, are in it for the knowledge and the spreading thereof. Any papers he publishes have the grad students listed first (by order of work done on the project) and his name last. The scientific journals know that the professor's name is last (and of course, followed by the telling doctoral title) as most professors want to give the credit to those who need

Re:

[mea37 (1201159)]

Careful saying things like that around the professor, or he will indeed colour you cynical. Using a laser.

Re:

[UnanimousCoward (9841)]

*Yawn* Wake me up when the post-grad develops transparent aluminum. Beam me up, Scotty!

Re:

[Speare (84249)]

This argument is like the quarterback vs the coach.

While the postgrad may have done 99.9999999% of the annoying and tedious labor-intensive development of the concept, it is often the case that such partnerships start with a short conversation in a hallway, where either one of them could rightly claim to have spawned the insightful flash that led to the exercise in the first place, and neither one of them could rightly deny the claim of the other. Add that to the fact that the lab is provided by the prof

Re:

[servognome (738846)]

.. but when I see things like "professor and a postgrad have developed", I assume that the postgrad did all the work and the professor took most of the credit.

The postgrad probably did all the labor, but the professor probably came up with the idea, provided guidance, and secured the funding. Being a grad student is just like being an apprentice in any other walk of life.

Next steps

[SSKennel (22926)]

Can transparent aluminum be far behind?

Re:

[oneiros27 (46144)]

No for two reasons:

First, this has to do with surface reflection, and transparency would require the light to go _through_ the material, not simply absorbed or reflected. And second, for it to be far behind, that'd suggest it hasn't already been done:

• http://science.slashdot.org/article.pl?sid=04/08/23/1141217 [slashdot.org]
• http://science.slashdot.org/article.pl?sid=02/02/20/0358206 [slashdot.org]

Hey! Where's the

[wiredog (43288)]

"whatcouldpossiblygowrong" tag! Come on! They're giving lasers to butterflies!

poll

[Thornburg (264444)]

Quick Poll:

Did the poster and/or editor intentionally make the ambiguous statement about butterflies, knowing that it would lead to a discussion 80% about laser-wielding butterflies, with real article-related content left to battle with the usual jokes/OT garbage/etc for the remaining 20% of comments?

Possible Answers:

() Yes, and it's awesome.

() Yes, and it sucks.

() No, but it's awesome.

() No, and it sucks.

() CowboyNeal forced them to.

Coloured MacBook Pro?

[Midnight Thunder (17205)]

Hmm, I wonder whether I could get him to apply the process to my MacBook Pro? If he manages to get the technique to colour metal in industrial quantity that could be amazing.

Prior Art

[PPH (736903)]

Paint.

Re:

[JeepFanatic (993244)]

Are they ill tempered?

Re:

[SQLGuru (980662)]

Green Lantern still would have a cooler ring than you. Bilbo errr...Frodo, too.

Of course, how can Jed Clampett turn his black gold into a ring for Ellie Mae?

Layne

(Joking aside, I think it would a cool looking ring, too.)

Re:

[imgod2u (812837)]

Depending on who you're marrying, it might be amazingly appropriate.

Re:

[Farmer Tim (530755)]

From the summary:

This is very similar to the way that butterflies get the color in their wings.

Oh sure, they're just using the lasers to etch colourful designs onto their wings now, but give the little buggers a chance and they'll scale up the energy output. It's them or us, I tells you!

Re:

[CubicleView (910143)]

Offtopic I know, but I just googled The Gloom Wing Moth because I've no idea what you're on about and your post was the only hit I got. Google seems to have Slashdot in pratically real time these days.

Re:Butterflies with lasers

[Binestar (28861)]

*I* googled Gloom Wing Moth and I got his post, your post, this post and the post you're going to make in reply to it. Google is faster than real time today.

Re:Butterflies with lasers

[ThreeGigs (239452)]

Gloom Wing Moth

Phew!

Stop playing with the timestream folks, our universe was almost pinched off in a temporal loop.

Re:

[OneSmartFellow (716217)]

OK, you're a skeptic. Index of refraction is everything.