Distance vision testing assesses the clarity of central vision when viewing objects several metres away, typically using standard eye charts. It is a key component of a comprehensive eye examination.
Method
Patients read letters or symbols from a chart positioned at a set distance, such as 6 or 4 metres. Each eye is tested separately, with and without current spectacles, and the results are recorded as standard visual acuity measurements.
- Charts may be printed, projected, or displayed on digital screens
- Optotypes are scaled to account for varying test distances
- Lighting and contrast are controlled to meet recognised standards
- Pinhole testing may be used to estimate potential improvement with refraction
Clinical Uses
Distance acuity results help diagnose refractive errors, monitor disease progression, and assess eligibility for activities such as driving. They also provide baseline data before and after treatments.
- Changes over time can indicate new pathology or changes in refraction
- Results guide decisions about further testing and imaging
- Findings must be interpreted in the context of age and visual needs
- Reduced acuity prompts evaluation of optical, retinal, and neurological causes
