What is the difference between convex and concave lenses??
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Convex and concave lenses are two types of lenses with distinct characteristics. To understand the difference between them, we need to explore their shapes and how they refract light.
A convex lens, also known as a converging lens, is thicker in the middle and thinner at the edges. The outer surface curves outwards, like a bulging lens. This type of lens is capable of converging or focusing incoming parallel light rays to a point known as the focal point. The focal length is the distance between the center of the lens and the focal point.
On the other hand, a concave lens, also called a diverging lens, is thinner in the middle and thicker at the edges. The outer surface curves inwards, creating a thinner center part. Unlike convex lenses, concave lenses cause parallel light rays passing through them to spread out or diverge, rather than converging to a focal point. The focal point of a concave lens is a virtual point where the diverging rays appear to originate from when extended backward.
To summarize, the primary difference between convex and concave lenses lies in their shape and the way they bend or refract light. Convex lenses converge light rays towards a focal point, while concave lenses cause the light rays to diverge.