For other uses, see Zechariah. The male given name Zechariah is derived from the Hebrew ×Ö°×Ö·×¨Ö°×Ö¸×, meaning The Lord has remembered.. It has been translated into English in many variant forms and spellings, including Zachariah, Zacharias and Zachary. It was the name of various men in the Bible.
Double Refraction in Minerals Double refraction is the splitting of a single ray of light into two refracted rays when passing through an anisotropic mineral. All anisotropic minerals exhibit double refraction. Double refraction can be practically observed by placing a transparent Calcite (Iceland spar) crystal on a sheet of paper with a black dot on it. When the dot is viewed through the crystal, two dots are seen.
Definition: Refraction (optics) Refraction (optics) Refraction is the phenomenon that causes a light ray to bend when it hits an optical lens surface (or other medium that can act to transmit light e.g. water). Refraction occurs when light strikes the surface of the new medium. As the light enters a dense medium is slows the light wave down. The light is passing from an optical medium (like air) to another optical medium (like glass). As the density of the medium changes the light striking the surface is refracted.