Gantry Rotation
Data transmission and power cables in old scanners meant start - stop rotation
- series of images acquired by rotating clockwise and anti-clockwise for subsequent scans
- scan times down to ~1 s
Slip rings introduced in 1990 allowed continuous rotation
- Power and signals transmitted to rotating gantry using ‘brushes’ on static rings
- no need to start and stop rotation
- scan times as fast as 0.4 s