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Diverging Lenses

A lens which diverges light rays is called a concave lens. Concave lenses always produce virtual, upright and diminished images.

Lenses can either converge or diverge rays of light. In this lesson we will look at diverging lenses.

Let's recall, how does a convex lens work?

Can you guess what diverge means?

What do you think a diverging lens might do?

Here we can see parallel light rays being refracted by a diverging lens. From what point do the rays appear to be coming from?

Diverging lenses are known as concave lenses.

A way to remember this is concave lenses curve inwards, like the opening of a cave.

Pick all the statements below that you think are correct descriptions of real images.

You can select multiple answers

Pick all the statements below that you think are correct descriptions of virtual images.

You can select multiple answers

To find out where the image will be in a lens diagram, the first thing we do is to draw a straight line from the object through the centre of the lens. Does this ray get refracted? Answer 'yes' or 'no'.

Secondly, we draw a ray from the same point on the object, parallel to the principal axis. This ray will get refracted. Look at the diagram. If you trace this ray backwards, where does it cross the principal axis?

The image forms where the two rays intersect. Out of the following options, which best described the image formed?

A) Virtual, upright, and diminished. B) Real, upright, and diminished. C) Virtual, inverted, and diminished.

What kinds of images does a concave lens produce?

Out of the following options, which do you think are examples of concave lenses?

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To sum up

Lenses that diverge rays of light are called concave lenses. Concave lenses always produce virtual, upright and diminished images.

Examples

Glasses for short-sightedness, telescopes, binocular and cameras.