Term | Definition |
light ray | a straight-line beam of light as it travels outward from its source |
law of reflection | the angle between an incoming light ray and a surface equals the angle between the reflected light ray and the surface |
opaque | completely blocking light from passing through it |
transparent | letting all light through, so that objects on the other side can be seen clearly |
translucent | letting only some light through, so that objects on the other side appear blurry |
polarization | allowing light vibrations to pass through in only one direction |
refraction | the bending of light rays as they pass from one substance into another |
concave lens | a lens that is thicker at the edges than at the middle; as it curves inward, it spreads light rays apart, making images appear smaller |
convex lens | a lens that is thicker at the middle than at the edges; as it curves outward, it brings light together, making images appear larger |
prism | a cut piece of clear glass (or plastic) with two opposite sides in the shape of a triangle or other geometric shape |
spectrum | a band of colors produced when light goes through a prism |
primary color | red, green, or blue; mixing these colors can produce all the colors of the spectrum |
primary pigment | magenta, cyan, or yellow; materials with any of these colors absorb one primary color of light and reflect the other two |
electromagnetism | the production of magnetism by electricity (and the production of electricity by magnets) |
electromagnetic spectrum | all the wavelengths of visible and invisible light in order, from short(gamma rays) to long(radio) |
laser | a device that produces a thin stream of light of just a few close wavelengths |