低照度に於ける視標の認識域について

Recognition of the Visual Target in Lower Illumination

緒言

　暗順応状態での最小光度及種々なる低照度に於ける視標の認識能力域が，眼の高さの水平面上に於いて如何なる深度を有するかを実験し，その数値を形態的に作図し観察せんとす。

Plotting the recognizable sphere of the visual target by using each lower illumination on the vertical wall, the author studied on the illuminating condition of the sphere of the vi-sual field and also visual ability of poor sighted one and partial color blindness. In additi-on to the above I have tried to measure the decreasing visual field as correctly as possible by using the same.

The visual field increased in size by practice, developed in 80°~60° lines in dark night and especially remarkably in 90° line by the lower illumination as star night and moon night.