title: Optical projection mires for measurements of the radii of curvature of the cornea in biomicroscopes.
abstract: Keratometry is currently achieved by projecting a circular mire onto the patient's cornea and analyzing the size and shape of its reflected image. The projection mires are decisive for the precision of the measurement. We have previously developed a keratometric module for slit lamps, and the development of four projection mires are presented. Mire 1 is composed of optical fibers and electrical cables; Mire 2, 48 LEDs; Mire 3, optical fibers and no electrical cables; and Mire 4, mechanical parts--cable free. Mires 2-4 provide accurate keratometry measurements at slit lamps. Mire 4 is the most adequate for the clinical environment.
authors.affiliation: Departamento de Engenharia Eléctrica, EESC Universidade de São Paulo, São Carlos, SP--Brasil. liliane@sel.eesc.usp.br
authors.forename: Liliane
authors.initials: L
authors.lastname: Ventura
authors.forename: Cassius
authors.initials: C
authors.lastname: Riul
authors.forename: Sidney Júlio de Faria E
authors.initials: SJ
authors.lastname: Sousa
mesh_terms: D001331:Automation; D003315:Cornea / Q000473:pathology*; D003316:Corneal Diseases / Q000175:diagnosis; D019781:Corneal Topography; D004867:Equipment Design; D006801:Humans; D015233:Models, Statistical; D009885:Ophthalmology / Q000295:instrumentation* / Q000379:methods*; D055095:Optics and Photonics; D012029:Refraction, Ocular; D012107:Research Design