The human visual system has attained a remarkable level of sophistication. The scientists engaged in matching its performance by some electronic or chemical system can only marvel at its sensitivity, its compactness, its long life, its high degree of reproducibility, and its elegant adaptation to the needs of the human system. It is true that the attempts at man-made systems date back only a scant hundred years, while the human visual system has been millions of years in the making. But the human visual system had to emerge from some cosmic scrambling of the elements, repeated and repeated and repeated until by chance the happy combination fell into place. While there are few who would question the blind, probabilistic, evolutionary origin of the human species, there are none who can delineate the steps. The shortfalls have long since vanished without a trace.
KeywordsQuantum Efficiency Visual Process Human Visual System Dark Adaptation Human Vision
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