I need help finding the focal length of a single convex lens. The radius of curvature is 200mm. left side is air and the glass has a index of 1.5. I search on google but there was only formulas for think lens, convex and converge lends. I need the formula for a single convex lens. Any idea? I know the ray transfer matrix.
$\matrix{1 & 0 \cr \frac{n-n`/n`R} & \frac{n`/n}}$