Predicting optimal accommodative performance from measures of the dark focus of accommodation.

摘要: Leibowitz and his colleagues found that accommodation rests at an intermediate distance shows wide interindividual variation. They proposed this dark focus is useful for correcting anomalous refractive errors, but proposal was later questioned when different measurement techniques yielded discrepant values. The present study measured under two levels of visual attentiveness: (a) performing open-loop, active viewing task (aDF); (b) looking passively into darkness (pDF). These measures were then compared with optimal derived from accommodative response functions in bright dim luminance. aDF to be more myopic (nearer) than the pDF highly correlated optical distance. No significant relationship between findings confirm are affected by nonoptical aspects technique; they also suggest demand attention (aDF) yield values optimizing potentially reducing fatigue difficult situations.