📚 StudyHub

⚛️ Physics  ·  NEET & JEE

Difference Between Convex Lens and Concave Lens

Lenses bend light to form images. A convex lens converges rays while a concave lens diverges them.

In short

A convex (converging) lens is thicker in the middle and brings light rays together to a focus (positive focal length); a concave (diverging) lens is thinner in the middle and spreads light rays apart (negative focal length).

Convex Lens vs Concave Lens - Comparison Table

BasisConvex LensConcave Lens
ShapeThicker at centreThinner at centre
Action on lightConverges (brings together)Diverges (spreads out)
Focal length signPositive (+)Negative (−)
Image (usually)Real & inverted (or virtual)Always virtual, erect, diminished
CorrectsHypermetropia (long sight)Myopia (short sight)
UseMagnifying glass, cameraPeephole, spectacles for myopia

Want to understand this fully? Read the Physics notes on this chapter.

Frequently Asked Questions - Convex Lens vs Concave Lens

Which lens is used to correct myopia?
A concave (diverging) lens is used to correct myopia (short-sightedness) because it spreads the rays so the image forms on the retina instead of in front of it.
Does a convex lens always form a real image?
No. A convex lens forms a real, inverted image when the object is beyond the focus, but forms a virtual, erect, magnified image when the object is between the lens and its focus (as in a magnifying glass).

More Physics Comparisons

← All comparisons  ·  Read the notes

Practise Physics - Free →