Fundamentals of geometrical optics
Focus, focal distance, refracting power
The image focus is the image of the point towards infinity on the axis :
F' is the image focus,
is the image focal distance of the diopter.
The object focus is such that its image is to infinity on the axis :
F is the object focus
is the object focal distance of the diopter.
Figure 15
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f and f ' and the diopter refracting power Cv are linked by the following relationship :
