光学軸

(1)a line that passes through the center of curvature of a lens so that light is neither reflected nor refracted; "in a normal eye the optic axis is the direction in which objects are seen most distinctly"

(2)光が反射も屈折もしない、湾曲したレンズの中心を通る直線

(3)in a doubly refracting crystal, the line in the direction of which no double refraction occurs; "a crystal may have either one or two optic axes"

(4)複屈折結晶、線の向きに複屈折が全く起こらない

(1)