We compare and contrast concave and convex lenses by drawing ray diagrams. In this Closer Look segment on Lenses, we compare and contrast concave and convex lenses by drawing ray diagrams and ...

A plano concave lens is an optical lens with one concave surface and one flat surface. It has a negative focal length, and can be used for light projection, beam expansion, or to increase focal length ...

A periscope camera lens is a lens assembly that uses prisms, mirrors, or a combination of them to redirect light before it reaches the camera sensor. In doing so, it magnifies the image more so than ...

Light travels at different speeds based on the medium it passes through. For example, in a vacuum, it travels at 3.0 × 10^8 m/s in a straight line. But when directed towards glass, air, diamond, water ...