A technique of pumping a solid-state Laser in directions which are approximately transverse to its beam direction.

Side pumping is a technique of optically pumping a laser Gain medium where the pump Light is injected from the side in a direction which is roughly perpendicular to that of the laser beam. The Key advantage of side pumping is that it allows the use of pump sources with very low spatial coherence, such as arc lamps or high-power Diode bars. Also, side pumping makes it easy to combine multiple pump sources.