| |||
| circle of confusion (expressed as the diameter of the image formed by a lens of a point of light; the diameter of this tiny disk of light is an indication of the degree of correction of a lens); circle of least confusion (when a pencil of light from a point source does not, after passing through a lens, converge to an absolute point before diverging again, the diameter of the pencil at its narrowest is termed circle of least confusion) | |||
| circle of diffusion | |||
