[A design of refractometer based on blur circle]

Area of Science:

• Ophthalmology
• Optical Engineering
• Biomedical Devices

Context:

• Accurate refractive error measurement is crucial for vision correction.
• Existing refractometers may have limitations in convenience or accuracy.
• The blur circle theory offers a novel approach to eye refraction.

Purpose:

• To design and validate a convenient and stable eye refractometer based on blur circle theory.
• To optimize key design parameters like pupil diameter (PD) and node-to-fovea length (NO').
• To compare the accuracy of the developed refractometer with clinical optometry data.

Summary:

• Retinal blur circle analysis was performed using ZEMAX with established eye models.
• Optimized coefficients (PD = 4 mm, NO' = 20 mm) resulted in a highly accurate refractometer.
• Clinical data showed no significant statistical difference for myopia and astigmatism axial direction (P > 0.05), with 80% of astigmatism degree data within 0.75D of hospital measurements.

Impact:

• The developed blur circle refractometer demonstrates high accuracy and convenience.
• It holds potential as a new, advanced style of refractometer for future clinical applications.
• This innovation could improve the efficiency and reliability of optometric examinations.