The primary difference between convex lens and concave lens is that a convex lens converges light rays and focuses them to a point, while a concave lens diverges light rays, spreading them apart.
What is Convex Lens?
A convex lens is a type of optical lens that is thicker in the center and thinner at the edges. It is also known as a converging lens because it converges or brings together parallel rays of light that pass through it.
Convex lenses are commonly used in various optical devices such as cameras, eyeglasses, microscopes, and telescopes to focus light and form images. They have two principal focal points, one on each side of the lens, where light rays either converge or appear to diverge, depending on the orientation of the lens.
Convex lenses are characterized by their ability to produce both real and virtual images depending on the placement of the object relative to the lens.
What is Concave Lens?
A concave lens is a type of optical lens thinner at the center than at the edges. It is curved inward, causing parallel rays of light to diverge or spread out when they pass through it.
Concave lenses are used to correct nearsightedness (myopia) and are commonly found in glasses and contact lenses to help people see distant objects more clearly by diverging the incoming light before it reaches the eye’s lens.
Convex Lens Vs Concave Lens
The basic difference between a convex lens and a concave lens is given below:
| Property | Convex Lens | Concave Lens |
| Shape | Thicker in the centre, curved outward | Thinner in the centre, curved inward |
| Focusing Behavior | Typically creates virtual and diminished images | Thicker in the center, curved outward |
| Principal Focus | Real and located on the opposite side of the incident light | Virtual and located on the same side as the incident light |
| Image Formation | Can form both real and virtual images, depending on the object’s position | Typically forms virtual and diminished images |
| Common Applications | Magnifying glasses, cameras, telescopes | Correcting nearsightedness (myopia), correcting certain eye conditions, like presbyopia |