In Fiber optics, a band of wavelengths at which an Optical Fiber is sufficiently Transparent for practical use in communications applications. Synonyms spectral window, Transmission window. See first window, second window, third window.

In imagery, a portion of a display surface in which display images pertaining to a particular application can be presented. Note: Different applications can be displayed simultaneously in different windows. Window may also be a period during which an event can occur, can be expected to occur, or is allowed to occur.