Answer:
Some lenses are used to focus light to a pre-defined point based on the amount of curvature of their surfaces.
In a piano design convex, some surfaces are flat while others has positive lenses (biconvex)
Step-by-step explanation:
Solution
These lenses are applied to pay attention to light in a point pre-defined based on the amount of curvature of their surfaces.
For that of a plano-convex design, one surface has a positive curve and for biconvex lenses, both surfaces are positively curved while the other remains flat.
when used practically, plano-convex lenses are most commonly used where the object being imaged is far apart from lens.