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Updated: Jan 9, 2026
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Development of a Gaze-Contingent Display Framework Designed for Perceptual and Oculomotor Research with Simulated Central Vision Loss
Published on: April 11, 2025
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Shorter Viewing Distance Reduces Contrast in Man-Made Environments
William E Myles1,2, Sally A McFadden1,2,3, Quan V Hoang1,2,4
1Department of Ophthalmology, Yong Loo Lin School of Medicine, National University of Singapore, Singapore.
Ophthalmology Science
|December 1, 2025
Summary
Man-made environments, unlike natural ones, have spatial frequency (SF) content that changes with viewing distance. This deficit in contrast, especially at middle and higher SFs, may contribute to myopia development.
Area of Science:
- Vision Science
- Environmental Optics
Background:
- Myopia is linked to near-work, indoor time, and urban settings.
- The spatial frequency (SF) composition of visual environments may play a role.
Purpose of the Study:
- Investigate SF content in natural vs. man-made environments.
- Examine how viewing distance affects perceived contrast.
Main Methods:
- Analyzed 594 digital images from diverse Singaporean environments.
- Computed fast Fourier transform and measured contrast energy across SF octaves.
Main Results:
- Indoor and urban environments showed steeper SF gradients than natural scenes.
- Man-made environments lacked contrast at middle/higher SFs compared to nature.
- Contrast in man-made settings was scale-dependent, unlike natural environments.
Conclusions:
- Natural environments offer consistent SF contrast regardless of viewing distance.
- Man-made environments exhibit reduced contrast at closer viewing distances.
- This contrast deficit in man-made settings may contribute to myopia.
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