What does the term "visual acuity" refer to?

The term "visual acuity" specifically refers to the sharpness or clarity of vision. This measurement quantifies how well a person can see fine details at a specified distance, commonly assessed using an eye chart. Visual acuity is typically expressed as a fraction, such as 20/20, indicating what a person with normal vision can see at a distance of 20 feet. It is a critical component of visual function, influencing overall ability to perform tasks that require clear vision, such as reading or driving.

Other options relate to different aspects of vision. The perception of colors accurately pertains to color vision, which is distinct from visual acuity. The adjustment of the eye to different lighting conditions refers to adaptation, important for seeing in varying light, but not directly connected to the sharpness of vision. The total field of vision relates to peripheral vision and the extent of the visual field, which also does not define visual acuity.