Why do we see rainbow like colours on a compact disk?

Answer 1

the CD is read by a laser beam and the light refracted is read as the music you hear. so the tracks are basically a prism that will when the light hits right make a rainbow

Answer 2

My Dear friend If you need a technically supoportive answer then read the answer fully or else read just the first para thats enough.

It is very common to see rainbow patterns when you look at the surface of a CD, and also when you look at soap bubbles or a thin film of oil floating on still water. All three of these effects are created by constructive and destructive interference of the light hitting the film.

Technical Judgement
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Think about a very thin film of oil floating on water as an example. When white light strikes the film, most of it passes through it, but some is reflected off of the top and bottom layers of the film. In the same way, when you stand in front of a window in your house, you can see a reflected image in the window. Most of the light is passing through the window and out of the house, but some is reflected back at you. The light that reflects off the top layer of a film of oil travels a slightly shorter distance than the light reflecting off the bottom layer,

If the film thickness is on the order of the wavelength of light, then interference can occur. Violet light has a wavelength of about 4,000 angstroms (hundred-millionths of a centimeter), while red light has a wavelength of about 7,600 angstroms, so we are talking about an extremely thin film. white light is made up of all different colors of light.

Answer 3

Rainbow is formed whe there is spliting and recombination of rays by the water drops. Same phenomeno occurs with the fine split layer in the cd, and hence the formation of rainbow takes place.

Answer 4

It's the same thing as a prism. Just the simple bending of light.

Answer 5

Scattered light. Look up "prisms".