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Updated: Jul 17, 2026
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Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
Published on: September 16, 2025
Influence of eyelid position on wavefront aberrations.
Wei Han1, William Kwan, Jing Wang
1Department of Ophthalmology, The First Affiliated Hospital, Medical College, Zhejiang University, Hangzhou, China. hanweidr@hotmail.com
Summary
Eyelid position significantly alters wavefront aberrations, impacting eye measurements. Eyelash interference also causes significant errors in aberrometry output, affecting clinical accuracy.
Area of Science:
- Ophthalmology
- Optical Engineering
- Vision Science
Background:
- Wavefront aberrations are crucial for understanding visual quality.
- Eyelid position and eyelashes can potentially influence aberrometric measurements.
Purpose of the Study:
- To investigate how eyelid position affects wavefront aberrations.
- To determine the impact of eyelashes on aberrometry readings.
Main Methods:
- Three studies evaluated wavefront aberrations using different aberrometers (COAS, OPD Scan).
- Measurements were taken with normal, narrowed, and artificially obstructed palpebral apertures.
- Eyelash interference was simulated using artificial eyelashes.
Main Results:
- Narrowing the palpebral aperture significantly altered third- and fourth-order aberrations, including defocus, astigmatism, coma, and spherical aberration.
- Corneal topography showed changes in the superior corneal zone with narrowed eyelids.
- Artificial eyelashes significantly affected Zernike terms and aberration RMS values for specific pupil sizes.
Conclusions:
- Deliberate narrowing of the palpebral aperture significantly influences wavefront aberrations.
- Corneal curvature distortion due to eyelid pressure contributes to aberration changes.
- Eyelash interference introduces significant errors in aberrometry output, particularly with the COAS system.
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