FUJITSU MHT2060BH - Manual (Page 68)

Theory of Device Operation
4-14 C141-E203-01EN
4.7.2 Data-surface servo format
Figure 4.7 describes the physical layout of the servo frame. The three areas
indicated by (1) to (3) in Figure 4.7 are described below.
(1) Inner guard band (IGB)
This area is located inside the user area, and the rotational speed of the VCM can
be controlled on this cylinder area for head moving.
(2) Data area
This area is used as the user data area and the SA cylinder.
(3) Outer guard band (OGB)
This area is located at outer position of the user data area, and the rotational speed
of the spindle can be controlled on this cylinder area for head moving.