optical axis [`äp·tǝ·kǝl `ak·sǝs] ANATOMY An imaginary straight line passing through the midpoint of the cornea (anterior pole) and the midpoint of the retina (posterior pole). OPTICS 1. A line passing through a radially symmetrical optical system such that rotation of the system about this line does not alter it in any detectable way. 2. See <<optic axis>> |