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Published on: March 11, 2016
Retinal image quality in the human eye as a function of the accommodation
N López-Gil1, I Iglesias, P Artal
1Departamento de Física, Universidad de Murcia, Spain.
Vision Research
|November 3, 1998
Summary
Human eye accommodation slightly reduces retinal image quality, primarily due to accommodative defocus error. Other aberrations also change, making accommodated eye images more symmetric.
Area of Science:
- Ophthalmology
- Optical Engineering
- Physiological Optics
Background:
- Accommodation is the human eye's ability to change focus for near vision.
- Retinal image quality is crucial for visual perception.
- Understanding how aberrations change with accommodation is key to visual optics.
Purpose of the Study:
- To investigate changes in human eye retinal image quality during accommodation.
- To quantify the impact of accommodative defocus on image quality.
- To identify alterations in optical aberrations with accommodation.
Main Methods:
- Utilized a near-infrared double-pass apparatus to assess retinal image quality.
- Employed an artificial pupil with a fixed diameter.
- Estimated the modulation transfer function (MTF) of the accommodated eye, correcting for defocus error.
Main Results:
- A slightly better MTF was observed in the unaccommodated eye compared to the accommodated eye.
- Most MTF reduction with accommodation was attributable to accommodative defocus.
- Retinal image shape changed with accommodation, indicating alterations in other aberrations.
- Accommodated eye images generally showed increased symmetry.
Conclusions:
- Accommodative defocus significantly impacts retinal image quality.
- Accommodation alters multiple optical aberrations beyond simple defocus.
- Changes in aberrations during accommodation lead to more symmetric retinal images, potentially by reducing coma or increasing symmetric aberrations.
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