double convex lens
A double convex lens, or converging lens, focuses the diverging, or blurred, light rays from a distant object by refracting (bending) the rays twice. At the front side of the lens, the rays are bent toward the normal (the perpendicular to the surface) because the glass is a denser medium than the air, and, at the back side of the lens, the rays are bent away from the normal as the rays pass into the less-dense medium of the air. This double bending causes the rays to converge at a focal point behind the lens so that a sharper image can be seen or photographed.
A double convex lens, or converging lens, focuses the diverging, or blurred, light rays from a distant object by refracting (bending) the rays twice. At the front side of the lens, the rays are bent toward the normal (the perpendicular to the surface) because the glass is a denser medium than the air, and, at the back side of the lens, the rays are bent away from the normal as the rays pass into the less-dense medium of the air. This double bending causes the rays to converge at a focal point behind the lens so that a sharper image can be seen or photographed.
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