Inspiring from biology
Some frogs, such as the African clawed frog (Xenopus laevis), change colour to cope with sunlight and heat and also to improve their camouflage. They do this by activating cells in their skin that contain granules of melanin, the dark brown pigment. These colour-changing cells, called melanophores, are normally dark but can be triggered by a particular hormone released in the frog. When the hormone binds to the cell wall, it sets off a reaction that moves the pigment granules to the centre of the cell, making it look colourless. Once the hormone detaches, the melanin grains disperse throughout the cell, making it appear dark again." (Sample 2002:21
Did you notice that this biological technology is extremelly similar to electric activated two color liquid filled spheres , monitors !
I think nature is full of answers.
I will look in to color changing biological answers to synthetic living organism pigments to find new new technologies and post here.
May be there is a biological analog photoshop for color prints.
May be colors of our prints will change with daylight or heat or the under surface.
And may be color portraits will find the real color with owners touch !
Thank you ,
Mustafa Umut Sarac
Cephalopods (octopuses and squids) have far more impressive colour-changing mechanisms with a response time in fractions of a second. I think these are a lot more interesting!
-- Ole Tjugen, Luddite Elitist
I watched a TV programme about this a few years ago. They produced some fantastic psychadelic effects.
Originally Posted by Ole
"People who say things won't work are a dime a dozen. People who figure out how to make things work are worth a fortune" - Dave Rat.
Thank you Ole . When I first read below article , I found it Dutch Scientists have been used and inspired from these technology. This is about full spectrum monitor. They uses electrically controlled plastic muscle to control thousands of micro slits to crack light in to different spectrums. Only disadvantage was to need of uses high voltages for these muscles but they succeeded to lower it from 10000 volts to 500 volts.
Here is a article about basic descriprtion of natural color changing technology of cephalopods
May be piezo heads of inkjet printers inspired from this also .
I remember these colors are too much similar to Louis Comfort Tiffany and Nash Favrille Glass.
The patterns and colors seen in cephalopods are produced by different layers of cells stacked together, and it is the combination of certain cells operating at once that allows cephalopods to possess such a large array of patterns and colors.
The most well known of these cells is the chromatophore. Chromatophores are groups of cells that include an elastic saccule that holds a pigment, as well as 15-25 muscles attached to this saccule (Hanlon and Messenger 1996). These cells are located directly under the skin of cephalopods. When the muscles contract, they stretch the saccule allowing the pigment inside to cover a larger surface area. When the muscles relax, the saccule shrinks and hides the pigment. Unlike other animals, the chromatophores in cephalopods are neurally controlled, with each chromatophore being attached to a nerve ending (Messenger 2001). In some squid, each chromatophor muscle is innervated by 2 to 6 nerves that directly link to the animals brain (Messenger et al 2001).
In this way the animal can increase the size of one saccule while decreasing the size of another one right next to it. This allows the cephalopods to produce complex patterns (Messenger 2001, Messenger et al 2001), such as the zebra stripes seen in aggressive displays by male cuttlefish. The speed at which this can be controlled allows the animal to manipulate these patterns in a way that makes them appear to move across the body. In some species of cuttlefish, it has been noted that while hunting, the cuttlefish may produce a series of stripes that move down their bodies and arms. Some scientists have suggested that this could be used to mesmerize prey before striking, but the purpose of this behavior has yet to be proven. The pigments in chromatophores can be black, brown, red, orange or yellow. They are not responsible for producing the blue and green colors seen in some species. Interestingly, many deep water forms possess fewer chromatophores as they are less useful in an environment in little or no light.
Iridophores are found in the next layer under the chromatopphores (Hanlon et al 1990, Cooper et al 1990). Iridophores are layered stacks of platelets that are chitinous in some species and protein based in others. They are responsible for producing the metallic looking greens, blues and golds seen in some species, as well as the silver color around the eyes and ink sac of others (Hanlon and Messenger 1996). Iridophores work by reflecting light and can be used to conceal organs, as is often the case with the silver coloration around the eyes and ink sacs. Additonally they assist in concealment and communication. Previously, it was thought that these colors were permanent and unchanging unlike the colors produced by chromatophores. New studies on some species of squid suggest that the colors may change in response to changing levels of certain hormones (Hanlon et al 1990, Cooper et al 1990). However, these changes are obviously slower than neurally controlled chromatophore changes. Iridophores can be found in cuttlefish, some squid and some species of octopus.
Iridophores and chromatophores on skin oby Roger T. Hanlon) . B) Red and green iridophores visible on head of cuttlefish, sepia officinalis (CephBase image No. 1378 by James B. Wood).
f Sepioteuthis sepioidea (CephBase image No. 287
Leucophores are the last layer of cells (Hanlon and Messneger 1996). These cells are responsible for the white spots occurring on some species of cuttlefish, squid and octopus. Leucophores are flattened, branched cells that are thought to scatter and reflect incoming light. In this way, the color of the leucophores will reflect the predominant wavelength of light in the environment. In white light they will be white, while in blue light they will be blue. It is thought that this adds to the animal’s ability to blend into its environment. Figure 4. A) Leucophores (white areas) visible on skin of Octopus burryi (CephBase image No. 294 by Roger T. Hanlon). B) Octopus burryi showing white spots due to leucophores (CephBase image No. 42 by Martin A. Wolterding).
Cephalopod’s have one final ability to change color and pattern, the photophores. These produce light by bioluminescence (for more information see “How Light Effects Marine Organisms” in “Light, Color and Cephalopods”). Photophores are found in most midwater, and deep sea cephalopods and are often absent in shallow water species. Bioluminescence is produced by a chemical reaction similar to that of a chemical light stick. Photophores may produce light constantly or flash light intermittently. The mechanism for this is not yet known, but one theory is that the photophores can be covered up by pigments in the chromatophores when the animal does not wish for them to show. Some species also have sacs containing resident bacteria that produce bioluminescence such as the tiny squid Euprymna. Mid water squid use photophores to match downwheling light or to attract prey (Young and Roper 1977, Johnsen et al 1999)
It is the use of these cells in combination that allow cephalopods to produce amazing colors and patterns not seen in any other family of animal. However, not all species of cephalopod possess all the cells described above. For instance, photophores may be necessary for animals in deep water environments but are often absent in shallow water forms. Deep sea species may possess few or even no chromatophores as their color changes would not be visible in an environment with no light. Recent research has suggested that there may be some correlation between the amount of chromatophores (and hence the complexity of patterns available) and the type and complexity of a cephalopod’s environment. For instance, midwater species may possess fewer chromatophores. While species living in reef type environments may possess more.
"The nineteenth century began by believing that what was reasonable was true, and it wound up by believing that what it saw a photograph of, was true.
" - William M. Ivins Jr.
"I don't know, maybe we should disinvent color, and we could just shoot Black & White.
" - David Burnett in 1978
"Analog is chemistry + physics, digital is physics + math, which ones did you like most?
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