visual acuity
Học thuậtThân thiện
Definition
Noun: - Sharpness of vision; the visual ability to resolve fine detail: This term refers to the clarity or sharpness of sight, specifically the eye's capacity to distinguish the details and shapes of objects. It is typically quantified using an eye chart, such as a Snellen chart.
Usage
"Visual acuity" is a technical term used primarily in medical, optometric, and scientific contexts. It describes a specific, measurable aspect of eyesight. - It is often tested during an eye examination. - Results are commonly expressed as a fraction (e.g., 20/20 vision). - It is distinct from other aspects of vision like peripheral awareness or color perception.
Examples
- The optometrist measured the patient's visual acuity and prescribed new glasses.
- Good visual acuity is essential for tasks like reading, driving, and recognizing faces.
- The study examined how visual acuity changes with age.
Advanced Usage
- "Corrected visual acuity": The sharpness of vision achieved while wearing corrective lenses (glasses or contact lenses).
- Her corrected visual acuity was 20/20 with her new prescription.
- "Unaided visual acuity" (or "uncorrected visual acuity"): The sharpness of vision without any corrective lenses.
- His unaided visual acuity was insufficient for driving legally.
Variants and Related Words
- Acuity (noun): Sharpness or keenness, often used in senses other than sight (e.g., mental acuity). When used alone in a visual context, it is understood to mean "visual acuity."
- Snellen acuity (noun): A specific type of visual acuity measurement obtained using a Snellen chart.
Synonyms
- Eyesight sharpness
- Clarity of vision
- Resolution (of the eye) (in technical contexts)
Related Phrases
- 20/20 vision: A term representing normal visual acuity, meaning a person can see at 20 feet what a person with normal vision should see at 20 feet.
- Legally blind: A classification that often includes a specific threshold of visual acuity (e.g., 20/200 or worse in the better eye with correction).
Noun
- sharpness of vision; the visual ability to resolve fine detail (usually measured by a Snellen chart)