Eyewear is a term used to refer to all devices worn over both of a person's eyes, or occasionally a single eye (therefore known as a monocle), for one or more of a variety of purposes. Though historically used for vision improvement and correction, eyewear has also evolved into eye protection, for fashion and aesthetic purposes, and starting in the late 20th century, computers and virtual reality.
The primary intention of wearing eyewear can vary based on the need or desire of the wearer. Eyewear comes in different forms, such as glasses, contact lenses, sunglasses and many more. Eyewear (such as glasses and contact lenses) helps most people see clearer or read. Eyewear also can be used for protection, such as sunglasses which protect wearers from the Sun's ultraviolet rays which are damaging to the eyes when unprotected, eyepatches to protect injured eyes from further damage, or goggles which protect the wearer's eyes from debris, water and other chemicals. Variants of eyewear can conversely inhibit or disable vision for its bearers, such as blindfolds and view-limiting device for humans, blinkers for horses, or blinders for birds, especially poultry. Eyewear also exists for other specialized or niche purposes, such as active shutter 3D systems and anaglyph 3D glasses for stereoscopy, and night-vision goggles for low-light environments.
