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Blue-blocking Filters and Digital Eyestrain.
Tatsiana Palavets1, Mark Rosenfield
1SUNY College of Optometry, New York, New York *Rosenfield@sunyopt.edu.
Summary
Blue-blocking filters do not significantly reduce digital eyestrain (DES) symptoms. This study found no difference in DES symptoms between blue-blocking and neutral-density filters during near-vision tasks.
Area of Science:
- Ophthalmology
- Optometry
- Human-Computer Interaction
Background:
- Digital eyestrain (DES) encompasses visual and ocular discomfort from screen use.
- Modern digital displays emit significant blue light, potentially contributing to DES.
- Blue-blocking (BB) filters are marketed to alleviate DES symptoms, but evidence is limited.
Purpose of the Study:
- To investigate the efficacy of BB filters in reducing DES symptoms.
- To examine the impact of BB filters on visual and ocular parameters during sustained near work.
Main Methods:
- Twenty-three participants performed a 30-minute reading task on a tablet.
- A blue-blocking (BB) filter or a neutral-density (ND) filter (equiluminant) was used.
- Accommodative response, pupil diameter, and palpebral aperture were measured; DES symptoms were self-reported.
Main Results:
- The BB filter blocked 99% of blue light (400-500 nm).
- No significant difference in total DES symptom scores was found between BB and ND filters (P = .62).
- Accommodation and palpebral aperture showed no significant differences between filter conditions.
Conclusions:
- BB filters were not more effective than equiluminant ND filters in reducing DES symptoms.
- Current evidence does not support the use of BB filters for near work-induced asthenopia.
- Further research is needed to understand the causes and effective treatments for DES.
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