【正文】 ate an effective lighting design, the fundamentals above are used within an appropriate design approach. For videoconferencing, the design approach is based on the concepts of photography and videography. Many will be familiar with the traditional key, fill, and backlighting elements used in these fields. While the fill and key light concepts apply well to the architectural/videoconferencing environment, the traditional backlighting technique isn39。s remained constant throughout the evolution of videoconferencing technology: How can you provide good, fortable lighting to optimize the camera and video codec operation in an architectural environment rather than in a studio? Although it39。s field of view, most notably lighting the videoconference room39。s a light, neutral color. Lamps of consistent color temperature should be used throughout the room that are patible with the camera. The typical choice would be fluorescent lamps rated 3,000 K to 3,500 K. s expressed as candelas per square meter (footlamberts in the more obsolete English units).Luminaire refers to a plete lighting assembly including the housing, reflectors, and lamps. Only when it39。s a fairly simple question, the answer can be quite plicated.There must be some light in the room of the space you39。s back and side walls.Each of these three elements must be properly ddressed to create a good videoconferencing picture. The difficulty es in the application of these concepts to an architectural environment such as a conference room where studio lighting isn39。 Use large, directional luminaires for key lighting where possible to reduce glare for the participants. Spot fixtures may be required for presenters next to projected displays. Consider both key and fill light sources. The key light should be in the 400 to 500 lux range when measured with a vertically oriented light meter. s useful to note that exact conversions should be used when reporting measurements, but when both are given as criteria a simple conversion factor of 10 is often used instead of .Luminance is the luminous intensity from a surface in a particular direction. Luminance may be thought of in this discussion as the light reflected from a surface. It39。re designing just for the camera to produce an image, but making that image look good while maintaining a good projected video image can be easier said than done. On top of just getting the camera to produce a decent image, you also have to be concerned about what the codec will do to that image (particularly at low bit rates), putting more constraints on not just the lighting design but also the interior design of the room itself — once again going beyond the tenets of a basic AV system.Up until now, AV professionals haven39。t an acceptable option.Fortunately, there are many solutions. Several lighting manufacturers offer luminaires designed specifically for videoconferencing, most typically for providing good key lighting while providing good directionality to keep light off of the display area at the front of the room. There are many luminaires that provide good, even coverage of a wall without throwing light out away from the wall (often called “wall washers”