| A | B |
|---|
| ray | a straight line used to represent a light wave |
| regular reflection | reflection that occurs when parallel rays of light hit a smooth surface and all reflect at the same angle |
| diffuse reflection | reflection that occurs when parallel rays of light hit a rough surface and all reflect at different angles |
| plane mirror | a flat mirror that produces an upright virtual image the same size as the object |
| image | a copy of anobject formed by reflected or refracted rays of light |
| virtual image | an upright image formed where rays of light appear to meet or come from |
| concave mirror | a mirror with a surface that curves inward |
| optical axis | an imaginary line that divides a mirror in half |
| focal point | the point at which light rays parallel to the optical axis meet, or appear to meet, after being reflected (or refracted) by a mirror (or a lens) |
| real image | an upside-down image formed where rays of light meet |
| convex mirror | a mirror with a surface that curves outward |
| index of refraction | a measure of the amount of ray of light bends wihen it passes from one medium to another |
| mirage | an image of a distant object caused by refraction of light as it travels through air of varing temperature |
| lens | a curved piece of glass or other transparent material that is used to refract light |
| convex lens | a lens that is thicker in the center than at the edges |
| concave lens | a lens that is thinner in the conter than at the edges |
| cornea | the transparent front surface of the eye |
| pupil | the openingin the center ofthe iris through which light enters the inside of the eye |
| iris | the ring of muscle that controls the size of the pupil and gives the eye its color |
| retina | the layer of cells thatlines the inside of the eyeball |
| rods | cells in the retina that detect dim light |
| cones | cells in the retina that respond to and detect color |
| optic nerve | short, thick nerve that carries signals from the eye to the brain |
| nearsighted | a condition that causes a person to see distant objects as blurry |
| farsighted | a condition that causes a person to see nearby objects as blurry |
| telescope | an optical instrument that forms enlarged images of distant objects |
| refracting telescope | a telescope that uses two convex lenses to form images |
| objective | a lens that gathers light from an object and forms a real image |
| eyepiece | a lens that magnifies the image formed by the objjbective |
| reflecting telescope | a telescope that uses a concave mirror to gather light from distant objects |
| microscope | an optical instrument that forms enlarged images of tiny objects |
| camera | an optical instrument that uses lenses to focus light and film to record an image of an object |
| laser | a device that produces a narrow beam of coherent light |
| hologram | a three-dimensional photograph created using lasers |
| optical fiber | a long, thin stand of glass or plastic that can carry light for a ling distances without allowing the light to escape |
| total internal reflection | the complete reflection of light by the inside surface of a medium |
| transparent material | a material that transmits light without scattering it |
| translucent material | a material that scatters light as it passes through it |
| opaque material | a material that reflects or absorbs all ofthelightthat strikes it |
| primary colors | three colors that can be used to make any other color |
| secondary color | any color produced by combining equal amounts of any two primary colors |
| complementary colors | any two colors that combine to form white light or black pigment |
| pigment | a colored substance used to color other materials |
