The Change in Refractive Power of the Human Eye in Dim and Bright Light

摘要: It has been reported that the human eye behaves as though relatively short-sighted in dim light. Observers tend to compensate for this change by setting optical instruments more negatively than bright New measurements of telescope settings 21 observers reveal an average increase power light 0.59 diopter (range +1.4 diopters −3.4 diopters). The dilation pupil does not contribute significantly phenomenon. chromatic aberration was measured 14 with a specially designed spectral stigmatoscope. refractive increases about 3.2 between 750 and 365 mμ. For reason Purkinje shift maximum visual sensitivity from 560 mμ 505 produces relative myopia 0.35 0.40 diopter. Persons who display changes larger or smaller do so because involuntary accommodation In enters state fixed focus, little different its condition when is paralyzed homatropine. may be relaxed, it add much 3 eye. Experienced focus close optimal determined objectively. Departures 0.5 either direction depress acuity. concluded 0.4 justified on basis Many gain further advantage individual adjustments light, appropriate their accommodative behavior.