光学存储系统

与磁存储器相比，光存储器是一种相对较新的辅助存储介质。它提供了一种有希望的用于大容量二级存储的随机介质，因为它可以在有限的空间中存储大量数据文本。

光盘存储系统由旋转的磁盘组成，该磁盘有涂层。使用薄金属或其他高反射率的材料。激光束技术用于在磁盘上记录/读取数据。因此，光盘也被称为激光盘或光学激光盘。

特性 ：-

1. 存储容量 –
   它是指可以存储在光学存储系统中的数据量。它与光斑的大小和磁盘的几何尺寸成正比。
2. 数据传输率–
   它是指可以从光学存储系统读取数据的速度。这取决于驱动器的线密度和转速。
3. 访问时间–
   它是指从光学存储系统访问所需数据所花费的时间。它与磁头的重量和磁盘的旋转速度成正比。

优缺点：-

S.No.	Merits	Demerits
1	The cost-per-bit of storage for optical disks is very low.	It is read-only (permanent) storage medium. Data once recorded, cannot be erased and hence, the optical disks cannot be reused.
2	The use of a single spiral track optical disks an ideal storage medium for reading large blocks of sequential data such as music.	The data access speed for optical disks is slower than magnetic disks.
3	Due to their compact size and light weight, optical disks are easy to handle, store, and port from one place to another.	It requires a more complicated drive mechanism than magnetic disks.