Null-screen based corneal topography using a smartphone

Adan Ayrton Rojas Lievanos; Manuel Campos-García; Marco Montes-Valles; Christian Camargo-Fierro; Violeta Guadalupe Camargo-Fierro

doi:10.1117/12.3017694

17 June 2024 Null-screen based corneal topography using a smartphone

Adan Ayrton Rojas Lievanos, Manuel Campos-García, Marco Montes-Valles, Christian Camargo-Fierro, Violeta Guadalupe Camargo-Fierro

Author Affiliations +

Proceedings Volume 13021, Optical Fabrication and Testing VIII; 130210N (2024) https://doi.org/10.1117/12.3017694
Event: SPIE Optical Systems Design, 2024, Strasbourg, France

Conference Poster

Abstract

To assess the curvature of a fast free-form convex surface, such as the cornea of the human eye, a smartphone corneal topographer based on the null-screen method has been developed. The null screen consists of a semiradial distribution of ellipse-shape dots arranged on a conical surface so that, when reflected from a test surface, it forms an ordered set of circular dots if the surface is perfect. Any deviation from this geometry is indicative of surface defects. To demonstrate that the corneal topographer provides reliable results on the topography of the human cornea, in this work, we set out to perform a calibration of the corneal topographer using a reference sphere with geometric parameters 7.8 mm radius and 12 mm diameter. We use a normal iterative method to reconstruct the surface shape and obtain the corneal topography.

(2024) Published by SPIE. Downloading of the abstract is permitted for personal use only.

Citation Download Citation

Adan Ayrton Rojas Lievanos, Manuel Campos-García, Marco Montes-Valles, Christian Camargo-Fierro, and Violeta Guadalupe Camargo-Fierro "Null-screen based corneal topography using a smartphone", Proc. SPIE 13021, Optical Fabrication and Testing VIII, 130210N (17 June 2024); https://doi.org/10.1117/12.3017694

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available