The SI unit of the power of a lens is:
Dioptre
The power of a lens is a measure of how strongly it converges or diverges light and is defined as the reciprocal of its focal length in metres: \(P = \dfrac{1}{f}\).
Its SI unit is the dioptre (D), which equals one reciprocal metre. Metre and centimetre are units of length or focal length, not power, and lumen is a unit of luminous flux, unrelated to lens power.
Important Questions from Optics
Who was the first one to use a glass prism to obtain the spectrum of sunlight?
Twinkling of stars is due to:
In which a convex mirror is used?
A. Rear View mirrors in vehicles
B. Glass windows
C. Makeup Mirror
D. Kaleidoscope
What is the reason for formation of Mirage in desert?
An object is placed 10 cm in front of a lens. The image formed is real, inverted and of same size as the object. What is the focal length and nature of the lens?
