| achromatic lenses | combination of lenses that correct chromatic abberation |
| additive primary color | red, blue green for light |
| additive theory of color | combining additive primary to make color |
| angle of deviation | angle between the incident ray-emergence ray |
| aperature | opening into camera |
| astigmatism | when the cornea or the lens is shaped wrong, making the eye have different focal points |
| chromatic abberation | defects in lenses that cause white light to disperse into it's components |
| critical angle | when angle of refract is 90, it's angle of incidence that results in angle of reflection |
| diopters | unit used by opticness to describes-prescribe lenses |
| dispersion | separation of a beam of white light into it's component color |
| emergent rays | the ray the leaves the medium |
| emission spectrum | spectrum produced by a substance when heated to incandense |
| hypermetropia | (farsightedness) distance between lens and retina is too small |
| index of refraction | The ratio of the speed of light in vacuum, air, or other medium of reference |
| infrared | radiation beyond the end of spectrum |
| lateral displacement | the difference of path between incident ray and emergence ray |
| myopia | (nearsighted) distance between lens and retina is too great |
| Newton's disk | disk painted with spectrcal colors rotating at high speed |
| persistence of vision | A visual phenomenon where an image is retained in the eye for a short period of time |
| presbyopia | a form of farsightedness in which it is difficult to focus on close objects or to read and occurs as a child ages. |
| recomposition | the recombining of colors of the spectrum for white light |
| refraction | The bending of light as it passes from one medium to another |
| shutter | controls light entering the camera |
| snell's law | is a formula used to describe the relationship between the angles of incidence and refraction |
| spectrograph | device that records spectrum on film |
| spectrometer | device that sends a parallel beam of light through a prism, then through two convergings lenses, then to an eye piece to produce visible spectrum |
| subtractive theory of color | begin with white light and then filters to absorb colors until desired color is left |
| total internal reflection | all light is reflected and none refracted |
| ultraviolet | reigon of the EM spectrum beyond visible violet |