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Related Experiment Video

Updated: Oct 3, 2025

$Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter$

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Published on: September 16, 2025

Objective Accommodation Amplitude Measurements Using a New Autorefractometer Device.

Kemal Ozulken¹, Hasan Kiziltoprak²

¹Department of Ophthalmology, TOBB ETU Medical Faculty Hospital, Ankara, Turkey.

Beyoglu Eye Journal

|February 21, 2022

Summary

This study shows that the Tonoref III autorefractometer can objectively measure accommodation amplitude (AA). Factors like age, refractive error, pupil size, and refractive surgery history influence AA, but gender does not.

Keywords:

Amplitude of accommodation autorefractometer objective accommodation test presbyopia pupil diameter

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Area of Science:

Ophthalmology
Optometry
Vision Science

Background:

Accurate measurement of accommodation amplitude (AA) is crucial for understanding visual function.
Objective methods for assessing AA are valuable complements to subjective techniques.

Purpose of the Study:

To evaluate the objective accommodation amplitude (AA) measurements using the new Tonoref III autorefractometer.
To investigate the influence of age, refractive error, and pupil diameter on objective AA.

Main Methods:

Three hundred subjects were categorized into five age groups.
Accommodation amplitude (AA) and pupil diameter were measured three times per eye using the Tonoref III device.

Main Results:

Mean AA was 1.63±0.061 D, with significant differences across age groups (p=0.000).
AA showed significant differences between emmetropic, myopic, and hyperopic groups (p=0.000).
Increased pupil diameter correlated with increased AA (p=0.000), while age correlated with decreased pupil diameter (p=0.000).

Conclusions:

The Tonoref III provides reliable objective AA measurements.
Age, refractive error, pupil diameter, and prior refractive surgery significantly impact AA.
Gender did not show a significant effect on AA measurements.