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New idea for making holographic animations in flash:

I’ve imported from photoshop a blurred grayscale image which in flash I’ve converted into a bitmap with a color threshold that makes it look like a contour map. Each colour is devided into separate layers and masks a grid. For each layer, the grid is a fraction larger – 2 pixels, the smallest being in the center, at th top level. This mimics the effects light waves have when bounced off an object, and viewd through a grid – an interfernece pattern – see below. When I get flash 8 I will use the bitmapData object to make an automatic color picker that will detect the different levels of the image, and bend an array of lines fractionally in the right directions. Intead of using a floating grid though, I want to find or make a refractive grid, like many rows of tiny crytals, so each eye gets a different view, making it more 3d.
go here to see experiment

Holographic images come from what is called an interference pattern. This is the pattern that is created when two light waves combine and create what is called constructive or destructive interference. This is when the the waves amplify each other or cancel each other out depending on how in phase they are.

They image that you see in the hologram, is the image of the the lines of light as they come in and out of phase, amplifying or decresing each other. In a real hologram, this is produced by bouncing a lasers off a three dimensional object that you want a holograph of, and recording those reflected beam, along with the beams from another laser as it intersects with those beams and creates the intgerference pattern.

Below is an example of what I’m talking about, simply created with a grid, overlaid on another grid which has been minutely distorted so as to come in and out of phases with the grid ontop, much as the light waves from a lasers would do.

go here to have alook

I have been experimenting with the idea of making holographic glasses that will make a computer screen image become 3d.

I know a holographic sticker works usesing a grate . Where your head is depends on what view of the image you get. The image is devided into a grate which is magnified through a repeated pattern of cerated plastic saw tooth shaped ridges, many mini prism all magnifying the image line under them.

The computer screen could be magnified in the same way. Only with stickers, the graTE usually runs horizontanlly, so what you see is two different, distinct perspectives, from above and below.

A fresnel lens is a radial grate. If you put it against the computer screen it creates a series of radiating rainbow spokes. This is the white light of the computer screen bieng magnified so you can see the RGB dots which make it up. If you hold it up to a white light you can see rainbow halos in it. these are the fringes of the white light as the different frequencies which make it up refract at different rates.

A true laser hologrpah works by capturing the interference of laser light waves as they bounce of the object. This works similarly to the office toys you often see that transpose the print of your hand.

If each pixel of the screen was composed of many different pixels each showing the object in all the angles from which the light bounces off it, the 3d impression, and this was viewed through some grate which revealed to the eye only the angle that was visible from the eyes positions, a 3dimensional effect would take place. And if the grate was removed, or on some surface protruding from the image on the screen, this would give each eye a slightly differeing perspective, creating a truly holographic effect.

have a look at this propotype model

Index of refraction is the change of speed of light waves as it passes through an object. From air through glass, the light will slow down, because glass has a higher index. When it leaves the glass again, it will return to the speed it travels in air.

Index of refraction s found by deviding the speed of light in a vacuum, or outer space by it’s speed in that material.

So the index of glass is 1.52.

When a light wave hits the surface of a material, some of that light is reflected back, depending on the angle. The light which passess through it is effected by the material, the different frequencies which make up a white light, all respond diffently to the material, and change their course to different degrees. Again when the light exists that material, it refracts again, the waves making up the visible spectrum can be seen spread out by this process of refraction when a beam of light passes through a crystal.

Light waves are like water or sound waves. They travel in waves called sine waves. When a pebble is dropped into still water, the ripples coming out from the the splash form a wave like pattern. The closesness of the ripples is called the frequency. Same when you hit a drum. When two different sources produce a wave in the same frequency, or in a multiple 2 or 4 or 6 or 8, for instance, those waves can co incide to create a bigger wave form. This is called constructive interference. When two waves are going in the same direction at the same time they can amplify each other. The seventh waves was a well known surfing label. This is because the ocean s waves have their own frequency to which they move. The 49th waves in ideal circumstaces, at 7 times 7, would be even bigger.

In the same way destructive interference works. Two similar waves, out of phase, that is when one is up, the other is down, when combine can cancel each other out. This principle can be seen in the knew anti noise technologynow available or use on aeroplanes.

This principle is used in holographics. A laser is monochromatic, it only has one frequency of light, and they are in phase, so all the waves are working together.

When you shine a laser onto an object, and shine another laser across the light that is bouncing off that object, what you get from where the two lasers cross paths is an interference pattern. Like dropping two stones into water and seeing the two waves of ripples as they intersect, some creating larger waves, others getting cancelld out. This pattern of lighter and darker lines is what is recorded on a very hi resolution film. The film grain so fine that the exposure needs to be very long and an isolation table to protect against vibrations is used.

Holograhics is the splitting up of a braod beam of white light into it’s different coloured parts. Into the beams which make it up. This is done as it passes through a grate, and as it does so to the human eye the white is spread over the reflectant surface, gradiated into its ingredients. Those ingrients, the spectrum of light waves to the human eye, range from ultra violet, at one end of the scale, throught the rainbow, to red, at the other.

The grate is like cutting through a marble cake, you see the different strata, as though light were seen from another dimension. The grate is made up of angled, in the case of a holographic sticker, groves running allong the surface, catching the light, and relflecting it back at aminutely different angle to the eye. On a CD the angles are the grooves running around the centre whole containing the data. The tranparent plastic is sputtered with a fine particle dust of aluminium, which reflects the data back efficiently enough for the laser to pick it up[.

A similar refraction, or deviding up of light can be seen when a crystal catches the light, casting a raindbow. This happens when white light passing into the crytal, is diverted, or refracted, of its main course as it enters the new substance of the crystal. As the crystal may have a uniform or ununiform index of refraction, nevertheless the light frequenceis all refract at slightly different angles, and again when the light is past out into the air. So the white light is spread across you wall, in different colours.

Holographic effects can be seen on the surfaces of pearls, and oil. On pearls this can be for two reason, one, what is called lustre, is the partial reflection of the the surface. Some of the light hitting it is bounced off, and some continues on to the deeper layers, each layer in its turn reflecting back the light, sometimes right back out. This is what happens with oil also, the surfaCE layer and the layer which is incontact with what it has slicked on bath reflect part of the light, and refract it too.

A very brightly coloured or highly contrasting tie worn by someone on television may give off a sort of hologrphic effect. This happens when thei tie is striped in any direction. When the bold colours of the tie are lit by the tiny red and blue and green colour dots on your television screen, the dots act like a grate, and the stripes of the tie in line or slightly out of line, or phase, form a gradiated pattern, so the tie which my have been a black and white striped tie, may become rainbow filtered, when sifted throught the grid of your television screen.