It is often said that lasers allow directed energy “at the speed of light.” While this is true along the direction of beam propagation, it is clearly not the case perpendicular to the beam, where beam scanning, tracking speed, and pointing stability are still (usually) limited by mechanical steering of a two-axis (azimuth-elevation, or “Az-El”) gimbal - see Fig. 5.1.
While gimbals are useful for scanning through a large field-of-regard (FOR), a typical beam control subsystem for a smaller FOR might look like that shown in Fig. 5.2. The figure shows a two-axis scan system for manufacturing that changes the angle of a beam incident on a focusing lens, rather than changing the pointing of the laser itself.
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