1.Previous
3.Next

to short focal length. The SI unit for optical power is the inverse metre , which is also called a dioptre (symbol: dpt or D) when used as a unit of optical power.

Explanation

The optical power of a device is related to its focal length by .

Converging lenses have positive optical power, while diverging lenses have negative power. When a lens is immersed in a refractive medium,

1.Previous
3.Next