How is a "hologram" created?
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You can tell the difference between a photo and a holograph by considering what a black and white photo is: it is a point-to-point recording of the intensity of light rays that make up an image. Every point records something, the intensity (i.e. the square of the amplitude of the electric field) of the light wave that illuminates that particular point. In a color photo, more information is recorded (in effect the image is recorded three times viewed through three different color filters), which allows a limited reconstruction of the wavelength of the light, and thus its color.\n\nHowever, the light which makes up a real scene is not only specified by its amplitude and wavelength, but also by its phase. In a photograph, the phase of the light from the original scene is lost. In a hologram, both the amplitude and the phase of the light (usually at one particular wavelength) are recorded. When reconstructed, the resulting light field is identical to that which emanated from the original scene, giving a perfect three-dimensional image (albeit, in most cases, a monochromatic one, though color holograms are possible).\n\nTo produce a recording of the phase of the light wave at each point in an image, holography uses a reference beam which is combined with the light from the scene or object (the object beam). Optical interference between the reference beam and the object beam, due to the superposition of the light waves, produces a series of intensity fringes that can be recorded on standard photographic film. These fringes form a type of diffraction grating on the film, which is called the hologram.\n\nOnce the film is processed, if illuminated once again with the reference beam, diffraction from the fringe pattern on the film reconstructs the original object beam in both intensity and phase (except for rainbow holograms where the depth information is encoded entirely in the zoneplate angle). Because both the phase and intensity are reproduced, the image "pops out"; the viewer can move her viewpoint and see the image rotate exactly as the original object would.\n\nBecause of the need for interference between the reference and object beams, holography typically uses a laser in production. The light from the laser is split into two beams, one forming the reference beam, and one illuminating the object to form the object beam. A laser is used because the coherence of the beams allows interference to take place, although early holograms were made before the invention of the laser, and used other (much less convenient) coherent light sources such as mercury-arc lamps.\n\nIn simple holograms the coherence length of the beam determines the maximum depth the image can have. A laser will typically have a coherence length of several meters, ample for a deep hologram. Also certain pen laser pointers have been used to make small holograms (see External links). The size of these holograms is not restricted by the coherence length of the laser pointers (which can exceed 1 m), but by their low power of below 5 mW.
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Hi, \n\nThat's too much like real work, but think about it like breaking pool balls in classical, and wave interference with quantum. \n\nHope that helps, \nMatt
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First, I would rule out warp speed.  The acceleration to reach it would smash a person to death and it would be very hard to impossible to travel faster than energy (the speed of light (E=mc^2).\n\nA replicator, would be very hard to accomplish.  You'd basically have to have a nuclear reactor to create the different molecules and one heck of a computer to align them all perfectly.  Then after all of that, is it economically feasible with as much energy as you'd expend, definitely not.\n\nThat leaves the holodek and cloaking.\n\nThe holodeck can partially already be done. Holograms can be projected to look like a person is standing there, but the problem with a holodek would be creating the force fields that are used so you can actually feel what projection looks like.  I doubt the force field could be created very easily, especially to that degree of feel without hurting the person who touches it.\n\nSo that leaves us with one left, cloaking.  Cloaking very easily could be possible if it isn't already possible.  Basically cover whatever object you want to hide in LCD screens and use cameras to record the surroundings around the object.  The views could be fed into the computers and onto the screens, making it look like the object wasn't even there from a distance.  I believe they showed something similar to that on one of James Bond's cars in a James Bond film.
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Here is the one I recently made:\n\nTake a transparency sheet and take ear buds (used for over head projectors)- lots of them. Dip the top of cotton part, of a bunch of ear buds, in glue and place them vertically on the transparent sheet. Go on doing this to make a square tightly filled with ear buds.  Note: you will have to give support to the ear buds until they are glued completely. \n\nNow you can apply the glue on the other side of ear buds and place another transparent sheet. Paint the central region of the ear bud-sticks with black colour. If required, cover the sides. It now looks like a square piece taken from a region in the plasma membrane.\n\nThe cotton ends now look like the hydrophobic layers on either end while the central region looks like the hydrophilic ends of phospholipids. If you want to elaborate, you can include proteins in the bilayer! You can use colour papers, ribbons etc (you can stiffen them by dipping in some glue and drying in the shape you want; I have also seen hair-bands available that form specific ion-channel like structures. Goodluck!
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http://hyperphysics.phy-astr.gsu.edu/hbase/hframe.html
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No surface can be 100% reflective. If you shot, say a laser at the most reflective surface possible, the reflected light would be less than the original beam.\nThere is no material that can allow light in and no light out. If you did create the sphere, you would need a little hole to aim a light source at, then you would have to close it quickly with the light source still shinning at the hole. Theoretically, with a 100% reflective surface and a vacuum inside the sphere, it would bounce around forever, until you broke it. A small flash would be seen, but the light energy would not compound and blow up.
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It works by having little mirror slices at different angles. As light is reflected off the orb, the little slices separates the light into several colours briefly and the process is repeated.
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Rather, by drawing a ray diagram you will see tt since the object is placed BETWEEN the focal point and the 'second focal point' (which is 2 x the focal length from the verticle), the image formed will be real, magnified and inverted.\n\nYou may want to check out the other variations for objects placed BEFORE the focal point, AT the focal point, AT 2 focal points away, or BEYOND 2 focal points as well.\n\nI dunno of any equation but i doubt there are any. the answer to ur qn is more of how does the object looks like. and to find out the size of the image it very much depends on the lens used. and perhaps you can apply some trigo.
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See  http://en.wikipedia.org/wiki/Lenticular_printing\n\nTh
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Try this. It's a tutorial on how to do one (below).
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you can try total internal reflection of light using a keychain laser (commonly availble) and tub filled with water. all you have to do is put a small piece of mirror in the tub filled with water, let laser fall upon it. see the trajectory of the reflected beam ofr different orintations/angle of reflections and you will find that for certain critical angle the reflected beam is trapped in the water due to the internal reflection of the laser. you can do the same thing by choosing a transparent bottle with a small hole on the curved surface close to the base. now fill it with water, and see that water flows out of the hole in a parabolic fashion, now shine the laser from the opposite side to illuminate the water column. take a white plastic sheet allow the water to fall upon it, you will find that the water emmits light. this also explains how fibre optics work.
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Light is refracted from a single point. Since the light which gets refracted into the same colors is all the same distance from the point source, a circle is formed.\n\n-Wied
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this is impossible to answer, there are many shapes that could be made this way.  do you have any other information like right angles or angles at corners?
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It is possible to encode sound into light, send it through space, then decode it back into sound.  You can do this by using the amplitude modulation of light.  Basically, you make the light "wiggle" and it then has a pattern of the sound vibrations.  See my sources for complete details.  It also explains step by step how to build such an apparatus.
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A hologram is a 3d image of an object.  If you look at one you may try to reach out and touch it but nothing is there.\n\nWe don't actually see objects, we see the light that is reflected from them.  If that light is bent somehow the image will change and the appearance of the object will be different than the case of no interference.  We try to extrapolate what was actually there based on the light that reaches our eyes (and the extrapolation is distorted if the light gets bent).\n\nIn short, the mirage is a real image, but it is not a real object.
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What's not clear is whether the image is a virtual or real one.\n\nFirst, consider a quick graphical, geometrical ray trace of a focusing \nmirror (let's assume it's spherical so that the analysis is simple).  I \nusually do this by drawing the reflector and locating its center of \ncurvature and focal point (which is just half the distance from the middle \nof the sphere to the center of curvature).  To look at image formation, I \ndraw a large number "1" where the object should be -- in this case, \noutside the focal point.  I then draw two rays from the top of the "1" -- \none parallel to the line from the center of the sphere throught the radius \nof curvature and one through the radius of curvature.  The first ray must, \nafter reflection, go through the focal point (because it acts as a \nparallel ray from infinity, which are all focused at the focal distance \nfrom any optic).  The second must just come back upon itself, because it \nis perpendicular to the reflector surface.  The intersection of the two \nrays is where the head of the image "1" is located.  In this case, it's \noutside the focal point.  I then do the same thing from the bottom of \nthe "1", and then draw the orientation of the imaged "1"...  It's clearly \ninverted and reduced in size and more than 1 focal length away from the \nmirror.  This is clearly the real image you referred to in your question.  \n\nWhere's the virtual image?  It's not there!  What you're observing is the \nreal image.\n\nTo understand this, consider what a virtual image is and how it's formed \nby an example.  A virtual image does NOT result from the convergence of \nray bundles at any real point in space... A virtual image is observed when \na situation arises rays from a single point appear to emerge from a point \nin space, but which doesn't correspond to any real point.  A good way to \nsee this is to turn the spoon around and look at the convex surface.  You \nsee yourself right side up!  If you do the ray trace using the method I \noutline above, you find an apparent convergence of rays behind the mirror \nwhich produces an upright image, which is just what you see in this case.  \nBut, since the spoon is silver, it's pretty apparent that there can't be \nany rays actually focused behind it -- so it's a virtual image.\n\nAn interesting thing occurs, however, when you flip the spoon back to the \noriginal configuration and move the object inside the focal point.  The \nimage you see is no longer inverted! And it's big!  If you do the ray \ntrace you find that the convergence of the rays which form the image is \nnow in back of the spoon, so that the image has shifted to an upright \nvirtual image which is magnified.  Try it with one of your spoons -- it \nreally works!\n\nAnd even more interestingly, if the object were placed exactly at the \nfocal point, all hell would break loose and what you would see would be a \ngiant blob filling the spoon that looks like nothing but a big source of \nlight.  In this case, there is neither a virtual nor a real image formed \nand the mirror/spoon is acting like a collimator -- turning all rays from \nthe object into parallel light streaming to infinity (roughly).\n\nI hope this helps!
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its called a GIF, you need to create that on your own.\n\ni suggest http://www.download.com for software. \n\nif your not tech savvy, i suggest you do not try it.