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[The significance of points alpha and beta on the dark adaptogram of the normal eye]
1Clinica Oftalmologică, Cluj-Napoca.
Purpose:
To determine the meaning of the points alpha and beta of the curve during dark adaptation.
Method:
In this paper I studied the curves during dark adaptation of the 48 normal eyes, examined at the Goldmann-Weekers adaptometer, for 30 minutes in standard conditions. The study had two stages: 1. To find out the mathematical low which defined the phenomenon; 2. To give a physiological explanation of the phenomenon.
Conclusions:
1. Distribution in time of point alpha and point beta recognized mathematical low of normal log. 2. The cones adapted to the dark into two phases: from the beginning of the adaptation to the point alpha; after point alpha till before point beta. 3. The rods adapted in three phases: a) before point alpha to the point alpha; b) from point alpha to the point beta; c) after point beta to the terminal threshold.
Conclusion:
Point beta gained a new meaning: point beta represents the end of the cone's adaptation.
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