Naipal Shivani, Khumalo Nqobile, Rahmtoola Muhammad, Chagi Sinoxolo, Didi Luyanda, Mthethwa Sandile, Ndhlovu Simmy, Persadh Bhavna, Rampersad Nishanee
Discipline of Optometry, School of Health Sciences, University of KwaZulu-Natal, Durban, South Africa.
Ophthalmic Physiol Opt. 2025 Jan;45(1):269-279. doi: 10.1111/opo.13410. Epub 2024 Oct 25.
Smartphones are the most frequently used digital devices globally with ~6.80 billion users. Despite the ubiquitous use of smartphones, limited information is known on the preferred viewing distance and font size of smartphone users. This study investigated viewing distance, font size and symptoms of eyestrain in non-presbyopic and presbyopic smartphone users.
In this quantitative research study, viewing distance and font size were measured in a group of non-presbyopes (n = 107) and presbyopes (n = 53), whilst participants viewed a text message and a web page on their own smartphone. Subjects also responded to a verbal questionnaire related to the characteristics of their smartphone and the computer vision syndrome questionnaire to assess symptoms of eyestrain. Data were analysed using descriptive and inferential statistics.
For the total sample, the mean viewing distance for a text message was 37.13 ± 8.82 cm (median 36.00 cm), and for a web page was 36.11 ± 7.98 cm (median 36.00 cm). Presbyopes had longer median viewing distances compared with non-presbyopes for a text message (41 cm vs. 34 cm, p < 0.001) and web page (40 cm vs. 34 cm, p < 0.001). The font size for non-presbyopes were <1.0 M whilst for presbyopes were >1.2 M. More than twice the percentage of non-presbyopes were classified with digital eyestrain (DES) compared with presbyopes.
Non-presbyopes used shorter viewing distances, smaller font sizes and were more predisposed to DES than presbyopes. The viewing distances adopted by presbyopes were similar to the conventional near-working distance of 40 cm. Eye care practitioners should consider viewing distances when assessing near-visual functions and prescribing a near refractive correction, particularly in non-presbyopes. There should be greater awareness of the importance of adopting appropriate viewing distances when using smartphones.
智能手机是全球使用最频繁的数字设备，全球约有68亿用户。尽管智能手机的使用无处不在，但关于智能手机用户偏好的观看距离和字体大小的信息却知之甚少。本研究调查了非老花眼和老花眼智能手机用户的观看距离、字体大小和眼睛疲劳症状。
在这项定量研究中，测量了一组非老花眼（n = 107）和老花眼（n = 53）在观看自己智能手机上的短信和网页时的观看距离和字体大小，同时参与者还回答了一份关于其智能手机特性的口头问卷以及电脑视觉综合征问卷，以评估眼睛疲劳症状。使用描述性和推断性统计方法对数据进行分析。
对于总样本，短信的平均观看距离为37.13±8.82厘米（中位数36.00厘米），网页的平均观看距离为36.11±7.98厘米（中位数36.00厘米）。老花眼在观看短信（41厘米对34厘米，p < 0.001）和网页（40厘米对34厘米，p < 0.001）时的中位数观看距离比非老花眼更长。非老花眼的字体大小<1.0M，而老花眼的字体大小>1.2M。与老花眼相比，非老花眼被归类为患有数字眼疲劳（DES）的比例高出两倍多。
与老花眼相比，非老花眼使用的观看距离更短，字体更小，并且更容易患DES。老花眼采用的观看距离与传统的40厘米近工作距离相似。眼科护理从业者在评估近视力功能和开具近视力矫正处方时应考虑观看距离，特别是在非老花眼中。使用智能手机时应更加意识到采用适当观看距离的重要性。
