CD Burner – How the CD Burning is done

Published:2012/9/27 21:23:00 Author:muriel | Keyword: CD Burner | From:SeekIC

CD burning is an amazing technology and its working principle is really fascinating. CD burners encode music and other datas on to the blank CD which can be retrieved through CD reading. CD stores the datas in digital form represented by a series of 1s and 0s. The 1s are represented by tiny bumps and the 0s as flat areas. Such millions of bumps and flats areas are present in a standard size CD. A CD is made from 1.2 mm thick, almost-pure Polycarbonate plastic and weighs 15–20 grams. From the center outward components are at the center (spindle) hole, the first-transition area (clamping ring), the clamping area (stacking ring), the second-transition area (mirror band), the information (data) area, and the rim. A CD is made up of a polycarbonate plastic known as Polymethyle Meta acrylic.The surface of the CD is coated with a thin layer of Aluminium to make it reflective, and is protected by a film of lacquer that is normally spin coated directly on top of the reflective layer, upon which the label print is applied. The bumps and flat areas are present on the reflective side of the CD which is arranged in continuous tracks. These tracks measures about 0.5 microns and can stretch about 5 Kms. During CD reading, a ‘Read laser beam’ passes over the flat area in the track. The laser beam will reflect back which will be passed onto a photo sensor assembly. The Photo sensor interprets the reflected laser light as 1. When the laser light bounce back from the bumps, the photo sensor will not get it and the CD player recognize it as 0. Blank CD The bumps are arranged spirally starting from the centre of the CD to the periphery. The motor in CD player spins the CD in a steady speed. The laser assembly of the CD player moves from the center to the periphery of the CD at a steady speed to retrieve the data. The CD player shows a slow spinning speed as the laser assembly move outwards to keep the bumps moving past the laser at a constant rate. The digital information retrieved by the photo sensor will be then converted into audio or video by the amplifier circuit. CD burring technique CD writer is used to burn the CD to record the data in the digital format. The CD burner darkens microscopic areas in the reflective side of the ‘Blank CD’. During burning, both reflective and non reflective areas are created in the CD that can be interpreted as 1 and 0 by the CD player. The CD burner has a laser assembly similar to the CD reader. But the laser is ‘Write Laser’ with high power around 40 mW. The write laser interacts with the CD and alters its surface.



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