Plano-convex lenses deliver less spherical distortion when focusing at infinity (when the imaged object is far away and the conjugate ratio is high). Therefore they are the go-to lens in cameras and telescopes. Maximum efficiency is achieved when the plano surface faces the desired focal plane, in other words, the curved surface faces the collimated incident beam. Plano convex lenses are a good choice for light collimation or for focusing applications utilizing monochromatic illumination, in industries such as industrial, pharmaceutical, robotics, or defense. They are an economical choice for demanding applications because they are easy to fabricate. As a rule of thumb, plano-convex lenses perform well when the object and image are at absolute conjugate ratios > 5:1 or < 1:5, so spherical aberration, coma and distortion are reduced. When the desired absolute magnification is between these two values, Bi-convex lenses are usually more suitable.