What is used to cool the inside of most pulsed lasers during operation?

In most pulsed lasers, distilled water is commonly used for cooling during operation due to its excellent thermal conductivity and availability. The cooling system is crucial in maintaining optimal operating temperatures within the laser, preventing overheating, and ensuring consistent performance. Distilled water acts efficiently to absorb and transfer heat away from the laser components, including the gain medium and optical elements, which can generate significant heat during operation.

While liquid nitrogen is effective in some high-performance applications, it is less practical for general use due to its extreme cold temperatures, which can lead to condensation and other complications. Air cooling is typically less effective, as air does not have the same thermal capacity as liquids, resulting in less efficient heat dissipation. An alcohol solution may be used in some specialized situations due to its lower freezing point, but it is not the standard practice for pulsed lasers. The choice of distilled water balances efficiency, cost, and simplicity, making it the most widely utilized coolant for pulsed lasers.