The advancements in science and technologies in areas like communication, power generation, transportation and printing have great impact on our life, making our life comfortable and easy. Computers and internet have taken communication to a higher level. Everywhere, in office, college or companies, computers are extensively used. People have stopped using files or records, but they use computer databases to store important data. Everything is becoming digital! No one writes anything on a piece of paper, even the most critical information stored in a computer. This wide usage of digital data required advanced memory storage options. Hard disks were extensively used, but there was need of something which was portable and easily available. The need was fulfilled by optical media. Optical media have revolutionized data storage. Before knowing about Optical disc duplicators, let us get a brief idea about optical drives and media.

The term ‘optical’ refers to something that uses light. Optical storage refers to a storage system which makes use of visible light to store data. The data is stored on to the media by making series of marks in a specific fashion that can be read using light. Examples of optical media include CDs, DVDs etc. A ray of laser light is made to fall on the rotating media (CDs or DVDs) to read data. Optical drive refers to a device that is capable of reading optical media. Laser light or electromagnetic waves are used to read/ write from/to the optical discs. A few years ago these drives were very expensive, but nowadays, they have become very cheap due to advancements in IC technology. Many modern optical formats like Blue-Ray discs have been developed.

Optical drives like CD players, DVD players, DVD recorders have become one of the important parts in consumer appliances. Optical discs and flash memory have replaced floppy disks and magnetic disks. The main parts in an optical drive are lens, photodiode, semiconductor laser which are contained in an optical path. A beam of laser light will be incident on the smaller laser light portion on the disc. The laser light is produced by the semiconductor laser which is passed through the lens to make it fall on the small laser spot only. In case of a writer, laser beam makes exact pattern like original CD/DVD by etching 0s or 1s on the disc. These patterns are reflected when laser light falls on them during rotation of the disc and the device is able to read the data. The shorter the wavelength, greater will be the storage capacity of the disc. CDs use 780nm wavelength light that is in the infrared range, DVDs use 650nm laser light that is red in color and blue ray discs use 405 nm that are violet in color. Shorter wavelength can be easily managed and hence more data can be stored on the disc. The photodiodes detects these laser beams and converts them to electrical signals. An organic dye is used to create the pattern in a blank disc by heating selective parts of the dye using laser beam. These marks are just like pits that reflect back laser beam, which is detected by the photodiode and converts them to electrical signals. The reading laser is comparatively weaker than the writing laser.

The process of recording information on to the optical media (CD or DVD) is called duplication. It is commonly called burning, since laser beam is used to heat up the dye to make marks according to certain pattern. There is another process called disc replication in which a optical disc is created by molding and the data cannot be added or removed. On the other hand, burning process is something that is carried out home. Replication is required when large number of copies of a CD/DVD is required say 500 copies or 5000 copies and is a professional way of producing discs. In replication process, the original CD/DVD is used in making a glass master from which stampers are made. By using high-tech injection molding, an exact replica of the master is made from the stamper. A reflective coat of aluminum is used and a layer of protective is used over it. Thousands of CDs/DVDs are produced in this fashion.

A new technology has been utilized to make the duplication process simple. A device is developed that produces many copies of the original disc simultaneously and it is called a duplicator. It is also commonly known as tower copier, since many optical writers are arranged one over another like a tower. This device does not require any software and the disc drives are connected through a controller card. It is the heart of the duplicator. The mechanism is very simple, the source disc has to be inserted into the source disc drive and number of copies to be produced should be mentioned. Just a button has to be pressed to initiate the burning process. Multiple discs are produced simultaneously depending on the bandwidth of the duplicator. Multiple disc duplicators can be connected through TCP/IP and the productivity can be boosted. These devices are suitable for companies and for those who need to distribute data on optical discs.

Truly, optical media technology has revolutionized data storage and without them, portability of digital data would not have been possible.