Water Droplets produces the Iridescent Colors......

Now Engineers from MITand Penn state University, found the Water droplets on a transparent surface can produce brilliant colors, without the addition of inks or dyes. The researchers have developed a model that predicts the color a droplet will produce, given specific structural and optical conditions. The model could be used as a design guide to produce, for example, droplet-based litmus tests, or color-changing powders and inks in makeup products.

a reply to: Karthikaqpt

??
I must be missing something. I've known water will do that for decades. You get rain on a window or windshield, the Sun breaks through and you get pretty colors.
The water acts as a prism.
Like I said...I'm probably missing something here.

a reply to: Karthikaqpt

Nice..

I guess we’ll soon see the “make-up printers” like “ink-jets” back in 80’s.



Good post. Start for you.

Bit lost here...thought that was a known phenomenon that even us plebs on the street have known since we were kids?

originally posted by: DAVID64
a reply to: Karthikaqpt
I must be missing something.

originally posted by: PhyllidaDavenport
Bit lost here...thought that was a known phenomenon that even us plebs on the street have known since we were kids?

I think the breakthrough here is the predictability of the color given specific precise conditions, not that the water can have colors:

The researchers have developed a model that predicts the color a droplet will produce, given specific structural and optical conditions. The model could be used as a design guide to produce, for example, droplet-based litmus tests, or color-changing powders and inks in makeup products.

But on a humorous note, this makes me think of "Crazy Rainbow Sprinkler Lady"

a reply to: Karthikaqpt

quantum lava pamps are right around the corner!

known from when the first guy thought to look at the morning dew and the sunlight hitting it .
how is this even news ?? 1 grade science class stuff .

O for the science behind it .
the water has tensile strength causing it to form a rounded surface .
Light then passes through the rounded surface causing it to bend and each color of light bends at a different rate splitting the light into its primary colors .
thus a rainbow is formed .
wile this is very very simplified response any one who liked science class could tell you by the fifth grade

originally posted by: midnightstar
known from when the first guy thought to look at the morning dew and the sunlight hitting it .
how is this even news ?? 1 grade science class stuff .

As I mentioned above, I think the "news" part is the precise predictability of the color, and how that predictability could be used as a tool.

The article goes on to say this:

The researchers have developed a model that predicts the color a droplet will produce, given specific structural and optical conditions. The model could be used as a design guide to produce, for example, droplet-based litmus tests, or color-changing powders and inks in makeup products.

Light bending paints the rainbow.

yea again so we make lead crystal to create what every display of colors we want . water can do teh same thimg .

How curved the surfice is makes the light bend a little different changing the way the colors show up .
Pridict it ? way more then that they can tell you excatly what color will be produced by what curve the water forms there is no pridicting involved just math .
wile the effect is cool it is very well understood .
Just seams a little elementary is all .
I am sure the Greeks understood this effect and could create any color they wanted 2000 years agaio .

originally posted by: midnightstar

Pridict it ? way more then that they can tell you excatly what color will be produced by what curve the water forms there is no pridicting involved just math .

Their paper reportedly says they can predict it, and even control the color produced.

By knowing the angle the light enters the droplet and the precise size of the droplet, they can determine how many times the light ray will reflect around the inside surface the droplet before exiting, and predict the interference patterns produced by those rays bouncing around inside.

It is that bouncing around of the light ray and the interference pattern produced that creates a specific color.

If they can precisely know/control the angle of the light entering the droplet, and know/control the precise size of the droplet, then they can predict or control the color, according to their research.

For example, if they want to make red, they precisely create a specific size drop and shine light through it at a precise angle, and they can get red. They could do the same for another color, controlling the drop size and/or the light angle.

For example, two rays of white light, containing all visible wavelengths of light, entering at the same angle and exiting at the same angle, could take entirely different paths within a droplet. If one ray bounces three times, it has a longer path than a ray that bounces twice, so that it lags behind slightly before exiting the droplet. If this phase lag results in the two rays’ waves being in phase (meaning the waves’ troughs and crests are aligned), the color corresponding to that wavelength will be visible. This interference effect, which ultimately produces color in otherwise clear droplets, is much stronger in small rather than large droplets.

“When there is interference, it’s like kids making waves in a pool,” Kolle says. “If they do whatever they want, there’s no constructive adding up of effort, and just a lot of mess in the pool, or random wave patterns. But if they all push and pull together, you get a big wave. It’s the same here: If you get waves in phase coming out, you get more intensity of color.”

yes ok all every one has pointed out is this has been known for well lord knows how long .
the article calling it predicting is badly worded .
Predicting something your unsure of the exact out come .
They can make the water drop so precise they can get it to show only one color that is doing the math you KNOW before you do it exactly what the out come will be .
I predict it will rain ( now I take a guess at the humidy the cold and heat and it just mite rain that is predicting something . At best a educated guess . With this kind of science it is not a guess on what color will be or if one will be at all we know .
I feal as most who like science do It should never involve Mystics .
you start with a theory then you do experiments to prove the theory once proven then you KNOW what you can and can not do in that area .

a reply to: midnightstar


Part of science is the ability to make predictions about a system based on the knowledge of how that system will work. In this case, if they produce a water droplet of a precise size and shape, and shine a light at a precise angle, than they are able to predict what color will be produced.

It's an experiment/process with a predictable outcome. Predictability is one of the hallmarks of the scientific process -- although (and here's where you are probably tripping up) the word "prediction" as used by science might have a different meaning to other people.

In science, a prediction means understanding what the outcome will be of an process based on information about that process and prior knowledge of how the process unfolds. Just because a scientific prediction might have been made using maths doesn't mean it wasn't a prediction, using the term the way science does.