Definition, Resolving Power, and Accuracy

Abstract

IN scientific writings the term “definition” most often refers to the clearness with which details are shown by optical instruments; but by a convenient generalisation it might be taken to mean the ratio of the greatest to the least quantity which any kind of apparatus can render apparent at the same time, being thus distinguished from “sensitiveness” or “resolving power,” which is determined simply by the smallest quantity measurable without reference to the size of the field.