7 (d.c.) Convex & Concave Lenses
Lenses
Anytime you look through binoculars, a camera, or eyeglasses, you are using lenses to bend light. A lens is a curved piece of glass or other transparent material that is used to refract light. A lens forms an image by refracting light rays that pass through it. Like mirrors, lenses can have different shapes. The type of image formed by a lens depends on the shape of the lens and the position of the object.
Convex Lenses
A convex lens is thicker in the center than at the edges. As light rays parallel to the optical axis pass through a convex lens, they are bent toward the center of the lens. The rays meet at the focal point of the lens and continue to travel beyond. The more curved the lens, the more it refracts light. A convex lens acts somewhat like a concave mirror, because it focuses rays of light.
Anytime you look through binoculars, a camera, or eyeglasses, you are using lenses to bend light. A lens is a curved piece of glass or other transparent material that is used to refract light. A lens forms an image by refracting light rays that pass through it. Like mirrors, lenses can have different shapes. The type of image formed by a lens depends on the shape of the lens and the position of the object.
Convex Lenses
A convex lens is thicker in the center than at the edges. As light rays parallel to the optical axis pass through a convex lens, they are bent toward the center of the lens. The rays meet at the focal point of the lens and continue to travel beyond. The more curved the lens, the more it refracts light. A convex lens acts somewhat like a concave mirror, because it focuses rays of light.
Concave Lenses
A concave lens is thinner in the center than at the edges. When light rays traveling parallel to the optical axis pass through a concave lens, they bend away from the optical axis and never meet. A concave lens can produce only virtual images because parallel light rays passing through the lens never meet.
A concave lens is thinner in the center than at the edges. When light rays traveling parallel to the optical axis pass through a concave lens, they bend away from the optical axis and never meet. A concave lens can produce only virtual images because parallel light rays passing through the lens never meet.
A telescope forms enlarged images of distant objects. A refracting telescope consists of two convex lenses, one at each end of a tube. To look at small, nearby objects, you would use a microscope. A microscope is an optical instrument that forms enlarged images of tiny objects. A microscope uses two convex lenses to magnify an object, or specimen.