（8）短距離（3米又は2.5米）視力表の有用性

Evaluation of the reduced distance test types

　視力表は視力の測定と屈折の自覚的検査に必要不可欠のものであるが，近年遠距離視力の検査距離を3米又は2.5米に短縮した短距離視力表が発売されている。この様に検査距離を短縮した場合の矯正視力並びに調節の変化について先に私は第3回関東眼科集談会に報告した。其後の山地氏の発表によつても，調節に対する補正さえ行えば2.5米用視力表を以て5米用視力表に全く代用し得る如き印象が与えられる。私は更に距離短縮の際の裸眼視力の変化，検査距離変動の影響を検討し，短距離視力表の有用性，使用上の注意を述べたい。

For testing visual acuity for distance it has been asserted which gave an impression that, as long as consideration is made for accomodation, the results were the same whether the test types were at 5 meter distance, the regular type, Or at 2.5 and 3 meters, the reduced distance type. In examining 51 Subjects by carefully checking the vision of the naked eye, the anther firitts that, When 3 meter is checked against 5, there is a difference of 0.25 to -0.5 D. ; when 2.5 is,compared to 5, there is that difference of -0.25 to -1.0 D.. In other words,a no-mal naked eye would register a. condition slightly myopic in results when the vision istested with a reduced distance test types instead of the regular 5 meters.