목적: 본 연구는 일상생활 속에서 흔히 접할 수 있는 근거리 시각매체의 재질과 글자크기에 따른 조절시스템(조절반응과 조절래그)을 비교 분석하고자 하였다. 방법: 특별한 안질환 및 굴절교정 수술경험이 없는 20~30세 성인 남녀 40명을 대상으로 시각매체의 재질(프린트용지, 신문용지, 잡지용지, 스마트폰, LCD 모니터)과 글자크기(6, 8, 10, 12)에 따른 조절반응을 양안 개방형 자동굴절계를 사용하여 측정 후 비교하였다. 결과: 실제 조절자극 유효굴절력은 $2.28{pm}0.11D$이고 실제 조절반응 유효굴절력은 $1.66{pm}0.30D$로 그 차이인 조절래그는 $0.62{pm}0.28D$였다. 시각매체의 재질에 따른 조절반응은 LCD 모니터를 사용한 경우 $1.35{pm}0.26D$(p=0.00), 스마트폰을 사용한 경우 $1.55{pm}0.25D$(p=0.04)로서 통계적으로 유의하게 낮은 조절반응을 보였고 조절래그는 LCD 모니터를 사용한 경우 $0.93{pm}0.24D$(p=0.00), 스마트폰을 사용한 경우 $0.73{pm}0.25D$(p=0.04)로서 통계적으로 유의하게 큰 조절래그를 보였다. 글자크기에 따른 조절반응과 조절래그는 통계적으로 유의한 차이를 보이지 않았다(p>0.05). 결론: 근거리작업 시 조절시스템은 시각매체의 글자크기보다는 시각매체의 재질에 따라 더 큰 영향을 받으며, 특히 비발광체 재질의 시각매체(프린트용지, 신문용지, 잡지용지)는 발광체 재질의 시각매체(스마트폰, LCD 모니터)보다 조절시스템의 관점에서 눈에 부담을 더 적게 주는 것으로 사료된다.
Purpose: This study was conducted to compare and analyze the accommodative system (accommodative response and accommodative lag) according to the material and font size of near visual media that we often encounter in daily life. Methods: Forty adult men and women aged 20 to 30 who not had specific ocular diseases and refractive surgery experience were examined to measure and compare the accommodative response according to the material of near visual media (print paper, newspaper, magazine, the I-Phone, LCD monitor) and font size (6, 8, 10, 12) by using both eyes open-view auto-refractometer. Results: The accommodative stimulus was $2.28{pm}0.11D$ and the accommodative response was $1.66{pm}0.30D$. The accommodative lag namely the difference between accommodative stimulus and accommodative response was $0.62{pm}0.28D$. The accommodative response according to material of visual media using LCD monitor was $1.35{pm}0.26D$ (p=0.00) and using the I-Phone was $1.55{pm}0.25D$ (p=0.04). Both of them were statistically significant lower. The accommodative lag using LCD monitor was $0.93{pm}0.24D$ (p=0.00) and using the I-Phone was $0.73{pm}0.25D$ (p=0.04) and they were statistically significant higher. The accommodative response and accommodative lag according to font size were not statistically significant (p>0.05). Conclusions: During near working, the accommodative system was more affected by material than font size of visual media. Especially, visual media of non-luminous material (print paper, newspaper, magazine) are considered fewer burdens on eyes than luminous material (I-Phone, LCD monitor) in terms of accommodative system.
