spectral rays
21luminescence — luminescent, adj. /looh meuh nes euhns/, n. 1. the emission of light not caused by incandescence and occurring at a temperature below that of incandescent bodies. 2. the light produced by such an emission. [1885 90; < L lumin (see LUMEN) +… …
22telescope — /tel euh skohp /, n., adj., v., telescoped, telescoping. n. 1. an optical instrument for making distant objects appear larger and therefore nearer. One of the two principal forms (refracting telescope) consists essentially of an objective lens… …
23photoreception — photoreceptive, adj. /foh toh ri sep sheuhn/, n. the physiological perception of light. [1905 10; PHOTO + RECEPTION] * * * Biological responses to stimulation by light, most often referring to the mechanism of vision. In one celled organisms such …
24eye, human — ▪ anatomy Introduction specialized sense organ capable of receiving visual images, which are then carried to the brain. Anatomy of the visual apparatus Structures auxiliary to the eye The orbit The eye is protected from mechanical injury… …
25Atom — The atom is the smallest unit of an element that retains the chemical properties of that element. An atom has an electron cloud consisting of negatively charged electrons surrounding a dense nucleus. The nucleus contains positively charged… …
26Indigo — This article is about the color. For other uses, see Indigo (disambiguation). Indigo   Spectral coordinates  Wavelength …
27Sunlight — This article is about light emitted by the Sun. For other uses, see Sunlight (disambiguation). Sunshine redirects here. For other uses, see Sunshine (disambiguation). For natural lighting of interior spaces by admitting sunlight, see Daylighting …
28radiation measurement — ▪ technology Introduction technique for detecting the intensity and characteristics of ionizing radiation, such as alpha, beta, and gamma rays or neutrons, for the purpose of measurement. The term ionizing radiation refers to those… …
29Star — For other uses, see Star (disambiguation) …
30Spectroscopy — Analysis of white light by dispersing it with a prism is example of spectroscopy. Spectroscopy ( …
