What Is Optical Media?

Date First Published: 13th March 2024

Topic: Computer Systems

Subtopic: Computer Hardware

Article Type: Computer Terms & Definitions

Difficulty: Medium

Difficulty Level: 4/10

CONTENTS

How Does Optical Media Work?
Examples Of Optical Media
Advantages and Disadvantages Of Optical Media

Learn more about what optical media is in this article.

Optical media is a type of data storage that uses a laser to read and write data from a removable plastic disc. It stores more data than magnetic storage media and has a longer lifespan.

Optical media is more durable and less vulnerable to environmental conditions than tape, but they are slower than HDDs and SSDs and offers lower storage capacities. With the popularity of the internet and the reduced costs of USB flash drives that store more data, the usage of optical media has declined.

How Does Optical Media Work?

Instead of storing data as magnetic charges, optical media encodes digital data using a series of bumps and pits on the underside of the metallic coating of a disc. As the disc spins in the drive, a laser scans those bumps and pits and decodes the patterns into readable data.

Examples Of Optical Media

Examples of optical media include:

CD - A type of portable optical media medium most commonly used to store digital audio recordings and data.
DVD - A type of optical media which can store any kind of digital data. It is most commonly used for storing films, music, and video games for distribution by suppliers.
Blu-ray - An optical disc data storage format designed to supersede the DVD format. It offers more than five times the storage capacity of DVDs. Unlike CDs and DVDs, which use a red laser to read and write data, a Blu-ray disk uses a blue laser, which increases data transfer rates and capabilities.

Advantages and Disadvantages Of Optical Media

The advantages of optical media are:

Although costs can vary depending on the type of discs and how they are used, the storage medium is inexpensive to manufacture.
They are durable. Optical discs are not vulnerable to data loss due to power failure and are much sturdier than magnetic tape.
They are suitable for storing data for long periods of time. When properly stored in dry, stable conditions, optical discs have a lifespan of several decades.

The disadvantages of optical media are:

Compared to HDDs and SSDs, data transfer rate is slow.
Optical discs are fragile and can be damaged by scratches to the top and bottom surface of the disc when not stored in a protective case. This can cause the optical disc to skip or stop working.
Compared to other methods of storage, storage capacity is more limited. The latest Blu-ray discs can store up to 128 GB, which is much less than HDDs or SSDs.