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Nicol prism

(Encyclopedia)Nicol prism nĭkˈəl [key], optical device invented (1828) by William Nicol of Edinburgh. It consists essentially of a crystal of calcite, or Iceland spar, that is cut at an angle into two equal piec...

haiku

(Encyclopedia)haiku hīˈko͞o [key], an unrhymed Japanese poem recording the essence of a moment keenly perceived, in which nature is linked to human nature. It usually consists of 17 jion (Japanese symbol-sounds)...

vision

(Encyclopedia)CE5 Optic nerve vision, physiological sense of sight by which the form, color, size, movements, and distance of objects are perceived. Defects of vision include astigmatism, color blindness, far...

diode

(Encyclopedia)diode dīˈōd [key], two-terminal electronic device that permits current flow predominantly in only one direction. Most diodes are semiconductor devices; diode electron tubes are now used only for a ...

aureole, in physics

(Encyclopedia)aureole ôrˈēōlˌ [key], in physics, luminous circle seen when the sun or other bright light is observed through a diffuse medium, i.e., smoke, thin cloud, fog, haze, or mist. It sometimes occurs a...

reflection

(Encyclopedia)CE5 Image formation by curved mirrors and lenses reflection, return of a wave from a surface that it strikes into the medium through which it has traveled. The general principles governing the ref...

Glauber, Roy Jay

(Encyclopedia)Glauber, Roy Jay, 1925–2018, American physicist, b. New York City, Ph.D. Harvard, 1949. From 1952 he was on the faculty at Harvard, where he became a professor in 1956. Glauber was the co-recipient,...

Akasaki, Isamu

(Encyclopedia)Akasaki, Isamu, 1929–2021, Japanese physicist, b. Chiran, Japan, Kyoto Univ. (BA, 1942), Nagoya Univ. (Ph.D., 1964). Aftger graduating from college, Akasaki worked as an engineer before ...

Heredia, José María

(Encyclopedia)Heredia, José María hōsāˈ märēˈä ārāˈᵺēä [key], 1803–39, Cuban journalist and poet. He is considered the most lyrical of the poets writing during the period of the wars of independen...

Rhodophyta

(Encyclopedia)Rhodophyta rōdŏfˈətə [key], phylum (division) of the kingdom Protista consisting of the photosynthetic organisms commonly known as red algae. Most of the world's seaweeds belong to this group. Me...