Question

State the Cartesian sign convention used in
ray optics.​

Answer 1

$\huge\underline{\underline\mathtt{Answer:-}}$

$\bf\large\underline\red{Cartesian \:sign \:convention \:used \:in \:ray \:optics.:-}$

(1) In a ray diagram, the principal axis is drawn horizontal and the incident rays are always shown directed from the left to the right.

(2) The pole of a spherical surface, or the optical centre of a lens, and the principal axis are respectively taken to be the origin and the x-axis of the Cartesian coordinate axes.

(3) Horizontal distances are measured from the origin; distances to the right are considered positive while those to the left negative.

(4) Vertical distances are measured from the principal axis; distances above are considered positive while those below negative.