Sunday, 21 May 2017

DESKTOP 1391 - CD SURFACE

You are looking at the surface of a music CD magnified about 400 times, a photomicrograph I took with a laser reflecting microscope.

The surface of a CD is made of a polycarbonate layer with moulded spiral tracks on the top. The data are stored on the CD as a series of minute grooves which are known as ‘pits’ encoded on these spiral tracks. The areas between the ‘pits’ are known as ‘lands’. In the photo, the ‘lands’ are the dark blue-black colour and the ‘pits’ are the various lighter colours, with red representing the deepest area of the ‘pits’.

These pits and lands do not represent the 1s and 0s, rather each change from pit to land or land to pit is interpreted as 0 while no change is read as 1. When you play the CD, the Read Laser bounces the light beams (not capable to modify the surface of CD) on the surface and detects the pits and lands. Each change between pit to land or vice versa is translated as zero and no change (pit to pit or land to land) is translated as one. These binary values form the actual data.

In case you are wondering, the CD is Beethoven's Symphony No 5 in C minor, op 67...

This post is part of the My Sunday Best meme,
and also part of the My Sunday Photo meme,
and also part of the Photo Sunday meme.

4 comments:

  1. Visible music - how interesting! Like modern art...

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  2. It looks so cool! #mysundayphoto

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  3. How interesting, what a great capture

    Thank you for linking up

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