What is the function of a "beam stop"?

A beam stop serves a crucial role in laser safety by absorbing or deflecting laser beams to prevent unintended exposure. When operating with lasers, there is always a risk of stray beams that could potentially cause harm to personnel or damage to equipment. A beam stop is specifically designed to be a protective barrier or absorption device that captures stray laser light, ensuring that it does not escape the intended pathway and thereby minimizing the risk of accidental exposure to the laser radiation.

The other choices do not accurately reflect the purpose of a beam stop. Enhancing the laser's intensity, focusing the beam, or reducing beam divergence involve manipulating the properties of the laser output rather than controlling where the beam goes or ensuring safety from accidental exposure.