"Ground signs" means signs supported by a structure which rests on or in the ground.
"Luminance" means the photometric measure of luminous intensity per unit area of light travelling in a given direction. Luminance is measured in candelas per square meters or "nits."
"Motion" or "moving" means the depiction of movement or change of position of text, images or graphics. Motion or moving shall include, but not be limited to, visual effects such as dissolving and fading text and images, travelling, running sequential text, graphic bursts, lighting that resembles zooming, twinkling or sparkling, changes in light or color, transitory bursts of light intensity, moving patterns or bands of light, expanding or contracting shapes, and similar actions.
"Nits" means a unit of measurement of brightness or luminance. One nit is equivalent to one candela per square meter.
"Off-premise sign" has the meaning ascribed to that term in Section 17-17-02108.
"On-premise sign" has the meaning ascribed to that term in Section 17-17-02109.
"Projecting signs" means signs which project obliquely or at right angles from the building or structure from which they are supported.
"Roof signs." Roof signs are signs which are erected on and supported by the roof of a building or structure.
"Static sign" means a sign that does not rotate, move, or have any appearance of changing or movement in the sign, sign components or structure. A "static sign" shall not include any sign that has any characteristics of a dynamic image display sign.
"Twirl time" means the time it takes for static text, images or graphics on a dynamic image display sign to change to different text, images or graphics.