Source: wikibot/optical-unit
= Optical unit
{wiki=Optical_unit}
An optical unit is a standard measure used in optics to quantify characteristics of optical systems, such as lenses, microscopes, or cameras. It can refer to a range of concepts depending on the context, including: 1. **Lens Focal Length**: This is a crucial optical unit, measured in millimeters (mm), that describes the distance from the lens at which parallel rays of light converge to a point (the focal point).