Physical Principles of DVD Technology

[Jaar-Gilon]

I have an assignment due tomorrow (year11) about DVD Technology and physics involved. I can't seem to find any info on the Physics behind DVD Technology or anything related to the topic, if anyone has a handy website or any info on Dvd Technology and related physics that would be awesome, cheers.

 

[Google_Spider]

http://www.howstuffworks.com/search.php

Search for 'DVD' you will get many results. Then try to find out whatever you want.

 

[Moetasim]

I can provide some information on the physical principles behind DVD technology. DVDs, or digital versatile discs, use a combination of optical and magnetic technology to store and play back digital data. The physics involved in DVD technology includes optics, electromagnetism, and materials science.

The main principle behind DVD technology is the use of lasers to read and write data on the disc. The laser is used to create pits on the surface of the disc, which represent the 1s and 0s of digital data. These pits are then read by the laser as it reflects off the disc, allowing the data to be retrieved.

The size of the pits on a DVD is determined by the wavelength of the laser used. DVDs use a red laser with a wavelength of 650 nanometers, which allows for smaller pits to be created compared to the larger pits on a CD (which uses a longer wavelength laser). This allows for more data to be stored on a DVD compared to a CD.

Another important aspect of DVD technology is the use of a reflective layer on the disc. This layer is made of a highly reflective material, such as aluminum, which reflects the laser light back to the reader. The pits on the disc disrupt the reflection of the laser, allowing the data to be read.

In addition to optics, electromagnetism plays a role in DVD technology through the use of a magnetic layer on the disc. This layer is used to encode additional data, such as subtitles or multiple audio tracks, on the disc. The laser is used to heat up the magnetic layer, allowing the data to be written onto it.

Finally, materials science is also involved in DVD technology. The disc itself is made of a polycarbonate plastic, which is a strong and durable material. The reflective and magnetic layers are then applied on top of the plastic, and a protective layer is added to prevent damage to the data layers.

I hope this information helps with your assignment. For more detailed information on the physics behind DVD technology, I suggest checking out scientific journals and textbooks on optics and electromagnetism. Good luck!