Thursday, February 16, 2012

Overview About CD Duplication

When doing the duplication of a CD, there are two major phases; first setting up the data, or information, to go onto the CD and then writing that details to the CD. Throughout the first phase, the information is placed into what is identified as an 'optical disc image, i.e. setting up an image that keeps the information that will then be transmitted onto the disc. To set-up this image, all the data that is to go into the disc is organized into a one file and arranged to suit what will be reading the CD. This not only allows the audience to recognize the information included on the disc, but also where the details are included on the disc so it can go directly to different parts of the information, like a particular music track. As soon as the information is gathered and all set for the CD duplication to take place, it is then arranged on the disc with a lead in, or start point, to tell the CD reader where the details starts with the disc, a table of contents to explain where and what the data is, and a lead out point to indicate where the information has completed.

Most computer programs for CD duplication use the typical file system ISO9660, or the Compact Disc File System. This standard was designed so that CDs will work in all compact disc players and readers. In this file program are different modes, with Mode 1 CD-ROM used for CD-ROMs and Form 2 CD-ROM Mode 2 used for audio and video data.

Nowadays lasers are used in most cases to write the information to the optical disc during CD Duplication. These types of lasers need to be adjusted to the right power, and this will rely on the kind of disc being used, what is going onto the disc and how. Read only cds use a natural dye on the area for the reflection variants, while re-write discs have a metallic alloy that is dissolved to produce reflection versions. Even so, a different laser calibration is expected to both write and read each kind of disc, as the comparison in reflectivity is different. Read only discs have a greater reflective variation, and therefore generally better quality, while re-write CDs have a lower reflective variation that has lower quality but the greater versatility of use of the disc due to its rewritable qualities.

Even though both kinds of duplication are included into most recorders these days, they do however call for the right connectivity. Again, this is generally consistent, with interior recorder drives using the ATA parallel connections and external drives using the PATA dive connection.


Laser technology is clearly a key element of disc duplication technology and lasers are always being created further. Because more and more details has been needed to fit onto a single disc, the wavelength of the lasers used has had to reduce in order to pack it in, with the corresponding laser used at the readers also needed to be this smaller duration.

Normally, the lasers used to duplicate a disc are significantly more effective than those used to read it, as the writing laser needs to modify the surface attributes of the disc while the reader laser needs to keep the surface unaltered. Laser recorders are officially called Laser Beam Recorders (LBRs) wherein most of the issues can now be different to generate the different wavelengths needed for different kinds of discs.

1 comment:

  1. Thanks rahul. You could share this information to your friends.

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