collimator

This term is primarily used in technical, scientific, and medical registers. It describes a precision instrument designed to eliminate divergence in a beam, ensuring that rays travel in a straight, parallel line. In an optical context, this is essential for telescopes and lasers to maintain image clarity and focus.

In medical radiology, the term carries a specific safety connotation. Here, the collimator acts as a shutter or mask to limit the X-ray field, preventing unnecessary radiation from hitting healthy tissue. It is a critical component of radiation protection and diagnostic precision.