Fig. 2.

Schematic of XFAST/YFAST raster scan. Solid arrows indicate B-scan acqusitions, dotted arrows indicate flyback. Left: An XFAST scan consists of B-scans parallel to the x-axis in the OCT scanner coordinate system. An YFAST scan (right) consists of B-scans parallel to the y-axis. $d_{fast}$ and $d_{slow}$ are interchanged between the two scan types. In both cases, the A-scan sampling locations form a 2D grid in the transverse plane of the scanner coordinate system. The transverse position of the first A-scan $p_1$is shown for each pattern.