THE RELATION BETWEEN VISUAL ACUITY AND ILLUMINATION.
THE RELATION BETWEEN VISUAL ACUITY AND ILLUMINATION.
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DOI：
10.1085/jgp.21.2.165
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发表时间：
1937-11-20
期刊：
影响因子：
--
通讯作者：
Shlaer S
中科院分区：
文献类型：
--
作者：
Shlaer S
1.描述了一种用于测量眼睛在不同照明下的视敏度的装置。测试对象的尺寸连续可变，并在30°视野中心距眼睛固定距离处呈现。通过人工瞳孔观察视场。尽管光源仅消耗110瓦，但可获得的最大强度足以覆盖白色光的眼睛的整个生理范围。提供了用于在1：1010的范围内以小步长改变强度的装置。2.使用两种不同类型的测试对象，一个破环和一个光栅，测量了两个受过训练的观察者的视力和照明的关系。两个测试对象的测量显示在0.16的视敏度处的断裂，所有低于视杆的值和高于视锥的值都是由视杆介导的。光栅在小于约30个光子的强度下给出较高的视觉敏锐度，而在该强度以上给出较低的视觉敏锐度。在相同条件下，光栅所能达到的最大视力比C光栅低30%左右。结果表明，当瞳孔直径小于2.3mm时，限制光栅分辨力的因素是瞳孔直径，而当瞳孔直径大于2.3mm时，限制光栅分辨力的因素是中心锥的尺寸。在此基础上从视敏度数据得出的视锥直径值与从单位面积的直接视锥计数得出的值一致。3.由两个测试对象制成的锥体的数据由Hecht为感光器系统导出的同一形式的稳态方程充分描述。这一事实，再加上对两个测试对象在可分辨面积方面的性质差异的某些考虑，导致了这样的结论，即细节感知是距离而不是面积的函数。同样，棒的所有数据也可以用同一方程的另一种形式来描述，尽管这些数据太不完整，不能使我们尽可能确定地选择这种形式。
1. An apparatus for measuring the visual acuity of the eye at different illuminations is described. The test object is continuously variable in size and is presented at a fixed distance from the eye in the center of a 30° field. Observation of the field is through an artificial pupil. The maximum intensity obtainable is more than enough to cover the complete physiological range for the eye with white light though only 110 watts are consumed by the source. Means for varying the intensity over a range of 1:1010 in small steps are provided. 2. The relation of visual acuity and illumination for two trained observers was measured, using two different types of test object, a broken circle and a grating. The measurements with both test objects show a break at a visual acuity of 0.16, all values below that being mediated by the rods and those above by the cones. The grating gives higher visual acuities at intensities less than about 30 photons and lower visual acuities above that. The maximum visual acuity attainable with the grating under the same conditions is about 30 per cent lower than that with the C. It is shown that the limiting factor in the resolution of the eye for the grating is the diameter of the pupil when it is less than 2.3 mm. and the size of the central cones when the pupil is larger than that. The value of the diameter of the cone derived on that basis from the visual acuity data agrees with that derived from direct cone count in a unit of area. 3. The data for the cones made with both test objects are adequately described by one and the same form of the stationary state equation derived by Hecht for the photoreceptor system. This fact, together with certain considerations about the difference in the nature of the two test objects with regard to the resolvable area, leads to the conclusion that detail perception is a function of a distance rather than an area. All the data for the rods can likewise be described by another variety of the same equation, although the data are too fragmentary to make the choice of the form as certain as might be desired.
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影响因子：
--
作者：
Freeman, E
通讯作者：
Freeman, E
DOI：
10.1085/jgp.19.6.979
发表时间：
1936-07-20
期刊：
The Journal of general physiology
影响因子：
--
作者：
Hecht S;Smith EL
通讯作者：
Smith EL
影响因子：
5.4
作者：
Reeves, P
通讯作者：
Reeves, P
DOI：
10.1098/rspb.1933.0020
发表时间：
1933-03-01
期刊：
PROCEEDINGS OF THE ROYAL SOCIETY OF LONDON SERIES B-CONTAINING PAPERS OF A BIOLOGICAL CHARACTER
影响因子：
--
作者：
Stiles, WS;Crawford, BH
通讯作者：
Crawford, BH
DOI：
10.1085/jgp.20.6.807
发表时间：
1937-07-20
期刊：
The Journal of general physiology
影响因子：
--
作者：
Smith EL
通讯作者：
Smith EL