Effect of the skew ray error on corneal topography using a cone topographer

Oliver Huerta-Carranza; Manuel Campos-García; Luis Ángel Pantoja-Arredondo; Fermín Granados-Agustín

doi:10.1117/12.3017219

17 June 2024 Effect of the skew ray error on corneal topography using a cone topographer

Oliver Huerta-Carranza, Manuel Campos-García, Luis Ángel Pantoja-Arredondo, Fermín Granados-Agustín

Proceedings Volume 13021, Optical Fabrication and Testing VIII; 130210A (2024) https://doi.org/10.1117/12.3017219
Event: SPIE Optical Systems Design, 2024, Strasbourg, France

Abstract

Most corneal topographers are based on the Placido disk, which is consists of a set of concentric rings illuminated in black and white. Each luminous ring is projected onto the corneal surface and its image produced by reflection is captured by a camera. When the corneal surface is symmetrical and aligned with respect to the optical axis of the corneal topographer, the image consists of concentric rings; therefore, displacements occur only in the radial direction. However, if the cornea lacks revolution symmetry, the image suffers deformations in both radial and azimuthal directions; therefore, corneal topography depends not only on the radial direction, but also on the azimuthal direction. This is known as the skew ray error. In this work, we present a numerical analysis on the effects on the corneal topography caused by skew ray error and show the advantages of using illuminated elongated ellipses, which are designed using exact ray tracing, to recover the corneal topography considering a conical corneal topographer.

Conference Presentation

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

Citation Download Citation

Oliver Huerta-Carranza, Manuel Campos-García, Luis Ángel Pantoja-Arredondo, and Fermín Granados-Agustín "Effect of the skew ray error on corneal topography using a cone topographer", Proc. SPIE 13021, Optical Fabrication and Testing VIII, 130210A (17 June 2024); https://doi.org/10.1117/12.3017219

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