| 释义 |
virtual focus
virtual focusn. The point from which divergent rays of reflected or refracted light seem to have emanated, as from the image of a point in a plane mirror.EncyclopediaSeefocusvirtual focus
vir·tu·al fo·custhe point from which divergent rays seem to proceed, or that at which they would meet if prolonged backward.virtual focusThe point at which divergent rays would intersect if extended backward.See also: focus |