Definition of optical memory

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Photonics Dictionary

optical memory: Optical memory is a type of data storage technology that uses light to read and write information. It typically involves the use of lasers to encode data onto an optical medium, such as a disc, and to retrieve that data by reading the reflected light patterns.

Storage medium: Optical memory systems use various types of discs, including CDs (compact discs), DVDs (digital versatile discs), and Blu-ray discs, as the primary storage medium. These discs are made of materials that can reflect light and have pits and lands (microscopic indentations and flat areas) that represent binary data.

Reading and writing mechanism: Data is written onto the optical medium by a laser that changes the physical or chemical properties of the medium (such as creating pits in a reflective layer). Data is read by shining a laser onto the disc and detecting the reflected light patterns, which vary based on the presence of pits and lands.

Capacity and performance: Optical discs can store varying amounts of data, with CDs typically holding up to 700 MB, DVDs up to 4.7 GB per layer, and Blu-ray discs up to 25 GB per layer. Performance in terms of read/write speed can vary based on the type of optical medium and the speed of the optical drive.

Durability and longevity: Optical media are generally durable and can offer long-term storage stability if properly cared for. They are resistant to magnetic interference and are relatively impervious to environmental factors like dust and fingerprints when handled properly.

Optical memory has been used for a wide range of applications, including data backup, software distribution, media storage, and archival storage.