Spot size and quality of scanning laser correction of higher order wavefront aberrations

D. Huang, M. Arif

Research output: Contribution to journalArticle

28 Scopus citations


PURPOSE: To investigate the effect of laser spot size on the outcome of aberration correction with scanning laser corneal ablation. METHODS: Numerical simulation of ablation outcome. RESULTS: Correction of wavefront aberrations of Zernike modes from second to eighth order were simulated. Gaussian and top-hat beams of 0.6 to 2.0-mm full-width-half-maximum diameters were modeled. The fractional correction and secondary aberration (distortion) were evaluated. Using a distortion/correction ratio of less than 0.5 as a cutoff for adequate performance, we found that a 2 mm or smaller beam is adequate for spherocylindrical correction (Zernike second order), a 1 mm or smaller beam is adequate for correction of up to fourth order Zernike modes, and a 0.6 mm or smaller beam is adequate for correction of up to sixth order Zernike modes. CONCLUSIONS: Since ocular aberrations above Zernike fourth order are relatively insignificant, current scanning lasers with a beam diameter of 1 mm or less are theoretically capable of eliminating most of the higher order aberrations of the eye.

Original languageEnglish (US)
Pages (from-to)S588-S591
JournalJournal of Refractive Surgery
Issue number5
StatePublished - Oct 6 2001


ASJC Scopus subject areas

  • Surgery
  • Ophthalmology

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