What is Near Vision?
Near vision is the ability to see and resolve fine detail at close range. It applies to tasks such as reading, writing, using a smartphone and other activities performed at typical working distances of approximately 33 to 40 centimetres from the eyes, which also represents the standardised distance used during near vision testing. Near vision is tested during a routine eye examination to assess clarity at close range and to detect changes in focusing ability that affect everyday visual tasks.
How is Near Vision Tested?
Near vision assessment is part of routine clinical practice in optometry and is defined within professional guidance frameworks set by organisations such as the General Optical Council standards and the College of Optometrists.
Near vision is assessed using a handheld near vision chart held at a standardised reading distance, typically 33 to 40 cm from the eye. Each eye is tested separately, with the patient wearing any reading correction they normally use. The optometrist records the smallest line of print that can be read accurately at the test distance.
Two main chart systems are used in UK optometry practice:
- N notation (Roman test types): N notation is the standard system for recording near visual acuity in UK optometry practice. The chart uses Roman test types in progressively smaller print sizes, with results recorded as N5, N6, N8, N10 and so on, where the number corresponds to the size of the typeface. N5 is the smallest print size on the standard chart. A patient who can read N5 at the standard test distance of 33 to 40 cm is considered to have normal near visual acuity.
- Jaeger chart: This is an older near vision testing system that records results as J1, J2, J3 and so on. Unlike N notation, Jaeger cards are not standardised — the actual print size corresponding to a given J value varies between different cards in circulation, which limits their reliability for consistent recording. The Jaeger chart is encountered less frequently in contemporary UK optometry practice.
The test distance is always recorded alongside the near vision result, as acuity values are only meaningful in relation to the distance at which they were measured. This ensures consistency and allows results to be compared accurately between assessments.
What is Normal Near Vision?
Normal near vision in a young adult is N5 at the standard test distance (33 to 40 cm). This reflects the ability to read standard-sized print clearly at a comfortable reading distance without visual strain. Near vision performance is influenced by age, refractive error and the clarity of the ocular media. In early adulthood, the focusing system of the eye maintains clear near vision without optical correction under standard conditions.
What is the Difference Between Near Vision and Distance Vision?
Near vision and distance vision are separate clinical measurements that assess different focusing demands of the visual system. Distance visual acuity measures clarity at 6 metres or more and is recorded using standard distance charts.
Near vision measures the ability to resolve fine detail at close range, typically the distances used for reading, screen use and other near tasks. In a young person with normal accommodation, both distance and near vision remain clear without correction.
As the eye ages, near vision reduces first because the focusing system loses flexibility, while distance vision often remains stable for longer.
Why Does Near Vision Change with Age?
Near vision changes with age due to presbyopia, which is the progressive loss of the eye’s ability to focus on close distances. Presbyopia is a universal age-related change in accommodative function, caused by the crystalline lens becoming progressively less flexible over time and reducing the range of focus available for near tasks.
This change begins around the age of 40 to 45 and continues to progress into the mid-60s. Presbyopia affects everyone to some degree as part of the normal ageing process and is not a disease.
Symptoms include:
- Difficulty reading small print at a normal reading distance
- Holding reading material further away to see it clearly
- Eye strain or headaches during prolonged near work
- Increased need for brighter lighting when reading
How is Reduced Near Vision Corrected?
Reduced near vision is corrected using optical devices that compensate for reduced accommodative ability.
- Reading glasses: Single-vision lenses prescribed specifically for near tasks at a defined working distance.
- Bifocal lenses: Spectacle lenses with two distinct optical zones. The upper segment corrects distance vision and the lower segment corrects near vision.
- Varifocal (progressive) lenses: Lenses that provide a continuous progression of power from distance to near correction without a visible dividing line.
- Contact lenses: Multifocal contact lenses provide multiple focal points, and monovision correction uses one eye for distance and the other for near tasks.
The choice of correction depends on prescription, habitual working distance, and daily visual requirements. An optometrist will advise on the most appropriate correction following a full sight test and assessment of visual needs, in line with College of Optometrists clinical guidance.