2D and 3D Measurement Algorithms for Real Front and Back Curved Surfaces of Contact Lenses

Kentaro Saeki, Kentaro Saeki, Decai Huyan, Akira Nakamura, Shin Kubota, Kenji Uno, Kenji Uno, Kazuhiko Ohnuma, Kazuhiko Ohnuma, Tatsuo Shiina

2021

Abstract

The 2D and 3D measurement algorithms for real front and back curved surfaces of contact lenses (CL) were developed. The purpose of 2D algorithm is to evaluate spherical lenses. We adopted the algorithm to be incident the probe light vertically along the curved surfaces of CLs under the condition that the difference of curvature radii between the front and back surfaces is small enough within numerical aperture (N.A.) of the optical probe. The vertical incidence against the curved surface is judged by using the intensity balance between OCT interference signals from both front and back surfaces of CL. As a result, the lens shape matched with the design value and RMSE of the thickness was 5.33 μm. Also, regarding the curvature radii, compatibility between this OCT device and the conventional device was indicated. In the 3D algorithm, we conducted a basic experiment using some special lenses in order to develop non-cylindrical lens measurement. By moving a 2-axis (vertical and horizontal) Micro Electro Mechanical System (MEMS) mirror with phase difference of 90,̊ it was designed to conduct circular scanning while maintaining vertical incidence of probe beam on the front surface of CL. The shape and the curvature radius was evaluated with simulation data under the same conditions. As a result, although it has an error against the design value, the result and the simulation result matched well.

Paper Citation

in Harvard Style

Saeki K., Huyan D., Nakamura A., Kubota S., Uno K., Ohnuma K. and Shiina T. (2021). 2D and 3D Measurement Algorithms for Real Front and Back Curved Surfaces of Contact Lenses.In Proceedings of the 9th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS, ISBN 978-989-758-492-3, pages 73-80. DOI: 10.5220/0010291800730080

in Bibtex Style

@conference{photoptics21,
author={Kentaro Saeki and Decai Huyan and Akira Nakamura and Shin Kubota and Kenji Uno and Kazuhiko Ohnuma and Tatsuo Shiina},
title={2D and 3D Measurement Algorithms for Real Front and Back Curved Surfaces of Contact Lenses},
booktitle={Proceedings of the 9th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS,},
year={2021},
pages={73-80},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0010291800730080},
isbn={978-989-758-492-3},
}

in EndNote Style

TY - CONF

JO - Proceedings of the 9th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS,
TI - 2D and 3D Measurement Algorithms for Real Front and Back Curved Surfaces of Contact Lenses
SN - 978-989-758-492-3
AU - Saeki K.
AU - Huyan D.
AU - Nakamura A.
AU - Kubota S.
AU - Uno K.
AU - Ohnuma K.
AU - Shiina T.
PY - 2021
SP - 73
EP - 80
DO - 10.5220/0010291800730080