Refractive error
How is refractive error diagnosed?
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| The Allegretto T-CAT topoliser |
Simple refractive error
Simple refractive errors are such as myopia, hyperopia and regular astigmatism are diagnosed by optometrists and ophthalmologists using trial lenses.
Higher order optical abberations
Irregular astigmatism is diagnosed using devices called abberometers, such as the A-CAT and T-CAT scanners of the Allegretto Wavelight laser system.