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Updated: May 17, 2026

Comparison of Agreement and Accuracy using Binocular Wavefront Optometer with Autorefractor and Phoropter
Published on: September 16, 2025
Design and validity of a miniaturized open-field aberrometer
Uday K Bhatt1, Amy L Sheppard1, Sunil Shah1
1From the School of Life and Health Sciences (Bhatt, Sheppard, Shah, Wolffsohn), Aston University, Birmingham, the University of Nottingham (Bhatt, Dua), Nottingham, and Midland Eye Institute (Shah), Solihull, West Midlands, United Kingdom; Topcon Corporation (Mihashi, Yamaguchi), Tokyo, Japan.
Purpose:
To design and validate a new miniaturized open-field wavefront device that can be attached to an ophthalmic surgical microscope or slitlamp.
Setting:
Solihull Hospital and Aston University, Birmingham, United Kingdom.
Design:
Comparative noninterventional study.
Methods:
The dynamic range of the Aston aberrometer was assessed using a calibrated model eye. The validity was compared with that of a conventional desk-mounted Hartmann-Shack aberrometer (Topcon KR1W) in dilated eyes. The instruments were used in random order, with measurements repeated 5 times to assess intrasession repeatability.
Results:
The open-field aberrometer had a large dynamic range of at least +21.0 diopters (D) to -25.0 D. It gave similar measurements to the conventional aberrometer for mean spherical equivalent (SE) (mean difference 0.02 D ± 0.49 [95% confidence interval]; correlation r = 0.995; P<.001), astigmatic components (J0: 0.02 ± 0.15 D; r = 0.977, P<.001; J45: 0.03 ± 0.28, r = 0.666, P<.001), and higher-order aberration (HOA) root mean square (RMS) (0.02 ± 0.20 D, r = 0.620, P<.001). Intraclass correlation coefficient assessments of intrasession repeatability were excellent (SE = 1.000, P<.001; J0 = 0.998, P<.001; J45 = 0.980, P<.01; HOA RMS = 0.961, P<.001).
Conclusions:
The new aberrometer gave valid, repeatable measurements of refractive error and HOAs over a large range. It can measure continuously, thus providing direct feedback on the optical status of the visual system to surgeons during intraocular lens implantation and corneal surgery.
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