Engineering:Automated refraction system

An automated refraction system is a group of ophthalmic devices used during an eye examination to aid in the determination of a person's refractive error and prescription for glasses or contact lenses.

The standard components of an automated refraction system are:

• an electronic and motor driven phoropter (auto-phoropter, auto-refractor head) used to present powered lenses in front of the patient's eyes,
• a hardware or software-driven controller that changes the lenses in the phoroptor for the subjective portion of the testing. A lens and prism system can also be used.
• an eye chart to aid in the determination of visual acuity during the test,
• an autorefractor that measures the patient's objective refractive error, normally used as the starting point of the subjective testing,
• an autolensmeter that measures the powers of the patient's current pair of glasses or contact lenses.

Automated refraction systems currently on the market vary in features, level of automation, ease of use, training required and documentation. Some systems contain automatic detection and compensation of common refraction issues such as accommodation and "over-minusing". An automated refraction is quick and painless.

Some advantages of automated refraction systems vs. manual refraction equipment are:

• less manual labour by the practitioner or technician
• more automation of repetitive and iterative tasks in the refraction
• ability to present former and new values quickly for validation
• reduced risk of human error
• direct transmission of results to Electronic Medical Record (EMR) software - see paperless office
• improved office efficiency