Presentation is loading. Please wait.

Presentation is loading. Please wait.

Lenses Convex lenses converge rays of light. Parallel rays converge a fixed distance away from the lens. This is known as the focal length.

Similar presentations


Presentation on theme: "Lenses Convex lenses converge rays of light. Parallel rays converge a fixed distance away from the lens. This is known as the focal length."— Presentation transcript:

1 Lenses Convex lenses converge rays of light. Parallel rays converge a fixed distance away from the lens. This is known as the focal length.

2 A concave lens spreads out incoming parallel beams. It has a negative focal length found by tracing back refracted parallel rays.

3 Short and long sight Long sighted people are unable to focus on nearby objects. A convex (converging) lens is used to correct this. Short sighted people have a retina which is too far away from the front of the eye. A convex (diverging) lens is needed to correct their sight.

4 Convex lenses act as magnifying glasses as long as the object is closer to the lens than its focal length.


Download ppt "Lenses Convex lenses converge rays of light. Parallel rays converge a fixed distance away from the lens. This is known as the focal length."

Similar presentations


Ads by Google