The vitamin essential for night vision is Vitamin A. It plays a critical role in maintaining healthy vision, particularly in low-light conditions. Vitamin A is a component of the protein rhodopsin, which is found in the retina of the eye and is crucial for the conversion of light into visual signals. Deficiencies in vitamin A can lead to night blindness or impaired vision, particularly in dimly lit environments. Sources of vitamin A include animal products like liver, fish, and dairy, as well as plant-based foods such as carrots, sweet potatoes, and leafy green vegetables that contain beta-carotene.