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Published on: January 16, 2020
A novel instrument for logging nearwork distance.
Tsz-wing Leung1, Daniel I Flitcroft, Josh Wallman
1Centre for Myopia Research, School of Optometry, The Hong Kong Polytechnic University, Kowloon, Hong Kong.
Summary
A new ultrasonic sensor accurately measures reading distances. High myopes read closer than low myopes, but self-reported distances were unreliable.
Area of Science:
- Ophthalmology and Vision Science
- Biomedical Engineering
- Optometry
Background:
- Myopia, or nearsightedness, is a growing global health concern.
- Understanding habitual reading distances is crucial for myopia research.
- Accurate measurement tools are needed to study nearwork behavior.
Purpose of the Study:
- To validate a novel ultrasonic sensor for measuring reading distances.
- To compare habitual reading distances between high myopes and low/non-myopes.
Main Methods:
- An ultrasonic nearwork analyzer was validated using artificial targets.
- Thirty Hong Kong Chinese adults (15 high myopes, 15 low/non-myopes) participated.
- Subjects read a newspaper for 10 minutes with their habitual visual aids while reading distance was recorded.
Main Results:
- The ultrasonic analyzer demonstrated accuracy and repeatability.
- High myopes exhibited significantly shorter reading distances (35.9 cm) compared to low/non-myopes (50.9 cm).
- Orally reported reading distances did not correlate with the device measurements.
Conclusions:
- The ultrasonic nearwork analyzer is effective for measuring reading distance in adults.
- A significant difference in reading distance was observed between high myopes and low/non-myopes.
- Further research is required to establish causality between closer working distances and myopia development.
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