Which term describes the illumination produced by a tubular electric discharge lamp or the fluorescence of phosphors coating the inside of a tube?

• A. Fluorescent Lighting
• B. Foot Candle
• C. Foot Panel
• D. Functional Pricing

Answer: (A)

Flourescent lighting describes the illumination produced by a tubular discharge lamp or the fluorescence of phosphors lining the inside of the tube. In these lamps, electric current excites mercury vapor to emit ultraviolet light, which then energizes the phosphor coating on the glass; the phosphors fluoresce, converting the UV into visible light that we see as the room’s illumination. This differs from a unit of brightness like foot-candle, which measures how much light reaches a surface, not the lighting type itself, and from terms like foot panel or functional pricing, which aren’t related to the light source.