| A | B |
|---|
| radiant energy | type of energy we call "light" |
| visible light | part of light we can see |
| ray | beam of light |
| speed of light | 186,000 miles per second |
| reflect | bounch off surface; form an image of an object, as in a mirror |
| refraction | the bending or redirection of light rays |
| transparent | lets light pass through ( ie. clear glass) |
| translucent | lets only some light pass through (ie. frosted glass) |
| opaque | lets no light pass through; creates shadow |
| prism | solid, transparent object; separates light that passes through it into its spectrum of colors |
| spectrum | continuous range of colors of light; red, orange, yellow, green, blue, and violet |
| primary colors | red, green and blue |
| absorb | to keep from passing through; to "swallow up" or take in |
| convex | bulging or curved outward |
| concave | hollowed or curved inward |
| converge | to come together at a point |
| diverge | to spread apart |
| cornea | transparent, rounded outer surface of the eye; helps to focus light on the retina |
| iris | colored ring around the pupil which expands and contracts to control the amount of light entering the eye |
| lens (in the eye) | transparent, convex body in the eye behind cornea and iris that helps to focus light onto the retina |
| optic disc | the "blind spot" in the eye where the optic nerve connects to the retina |
| optic nerve | thick cord of nerves that carries visual info. from the eye to the brain, where it is interpreted. |
| pupil | opening in the eye through which light enters. |
| retina | inner layer of eye or "screen" onto which images are projected; sensitive to light; passes info. about image through optic nerve to brain. |
| sclera | outer coating of eye, commonly known as the "white" |
