Autorefraction is an automated method of estimating refractive error using an instrument that analyses how light is reflected from the eye. It provides a rapid starting point for prescribing glasses or contact lenses.
How it Works
The device projects light into the eye and measures the pattern of its return after passing through the ocular media. Internal algorithms calculate spherical, cylindrical, and axis components of the refractive error.
- Quick and largely independent of patient responses
- Commonly used in routine clinic and screening settings
- Accuracy can be reduced by poor fixation, accommodation, or media opacity
- Often repeated several times and averaged
Role in Practice
Autorefraction results are typically refined by subjective testing rather than used alone. They are especially helpful for baseline measurements and for patients who struggle with long refraction procedures.
- Provides a useful check against manual techniques
- Paediatric and difficult cases may still require cycloplegic retinoscopy
- Regular calibration of instruments is important for reliability
- Values should be interpreted alongside visual acuity and clinical findings
