Thin Concave Lens

Concave lenses are thin, curved lenses that are thinner at the centre and thicker at the edges. Concave lenses cause parallel rays of light to spread apart, or diverge, as they pass through the lens. The focal length of all concave lenses is negative.

Example Concave Lens

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Example of a concave lens

The focal length, image position, and object position are all related through the thin lens equations