CLV (Constant Linear Velocity)

= velocidad lineal constante (VLC)
Ex: High recording density is also aided by rotating the disc at a constant linear velocity (CLV) with respect to the laser beam, rather than at a constant angular velocity (CAV), as is done with conventional audio discs and some video disc systems.

Refers to analog laser disks where the rotational speed varies (1800 to 600 RPM) so that the amount of track circumference spanned by the laser beam is the same for each video frame. Since the circumference of each revolution of the spiral track near the outer edge (later in the program) is greater, the disk is slowed down as the program progresses. A CLV disk holds about an hour's worth of program material on a side. Only the more expensive players can do slow motion or still frames when playing CLV disks, and usually only an even interlaced field or an odd interlaced field is seen at any given time. Incidentally the concept of CLV is used on all good tape recorders. You might observe that the cassette spool (or reel on an older machine) revolution speed varies. The take up spool mimics the behavior of the CLV laser disk, the beginning of the program's tape is at the center and the spool rotates fastes then.