What optical effect is caused by the lens in the eye when focusing on objects?

Accommodation is the optical effect caused by the lens in the eye when focusing on objects at varying distances. The lens changes its shape to adjust focus: it becomes thicker for nearby objects and thinner for distant ones. This process allows the eye to maintain a clear image as it shifts its gaze between different distances. Understanding accommodation is crucial in the context of night vision goggles, as the use of such devices can alter how the eye perceives distance and depth in low-light conditions. This ensures that when wearing NVGs, users can still effectively adjust their focus on various objects in their surroundings.