Task lighting

Often task lighting refers to increasing illuminance to better accomplish a specific activity. However, the illuminance level is not the only factor governing visibility. Contrast is also important, and a poorly positioned light source may cause contrast reduction, resulting in loss of visibility. The most important purpose of task lighting in the office is not increasing illuminance, but improving contrast. General lighting can be reduced because task lighting provides focused light where needed.

Different strategies for task lighting exist. The three main approaches are:

There are also other approaches to task lighting, for example under-shelf luminaires.

Other instances of task lighting are in machinery, where a specific work area needs illumination, and in workshops, where a task light may illuminate the actual working area. Special instances of task lighting are examination and operation lights for medicine and surgery, as well as the dentist's lamp. Task lamps are also used for many home tasks such as sewing, reading, small repairs, model construction, crafts, writing, and many other activities. The actual task may range from very small up to about as far as you may reach with your hands or available tools. Lighting of larger areas is beyond the scope of task lighting.

Localized lighting consists of a luminaire that provides ambient light as well as task light. Often it is an uplighter with a light source that is directed downward. It is intended to be mounted immediately over the workplace, and it can be either hung from the ceiling, mounted on the desk or a dividing wall, or it can be a free-standing floor lamp. Recessed lights placed directly over the work area are another common example.

Fixed task lighting refers to a non-movable light source dedicated to lighting a specific task. In kitchens, a homeowner may install several recessed "can" lights or under cabinet lighting to provide clear lighting onto the counters for cutting and preparing food. Having proper lighting when working with sharp knives is a critical component of injury prevention. Another form of fixed task lighting may simply be a table lamp positioned over one's reading chair.

The main feature of the freely adjustable task light is evident; one may adjust it freely at any whim or to suit one's needs. The lamp presents few limits to how one may position or orient the light. A freely adjustable lamp may include means for glare control, as a honeycomb or parabolic louvre that restricts the light output angle.

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Wikipedia