Task lighting

Often task lighting refers to office task lighting, where the task light is used to increase illuminance on the reading area. However, the illuminance level is not the only factor governing visibility. Contrast (vision) too is important, and a poorly positioned light source may cause contrast reduction, resulting in loss of visibility. Therefore, it can be argued that the most important purpose of task lighting in the office is not increasing illuminance, but improving contrast.

Different strategies for office task lighting exist, the main three different approaches are:
* Localised average lighting, where a lamp supplies both ambient light and task light
* Freely adjustable task light
* Asymmetric task light, where the lamp is placed at the side of the work areaThere are also other approaches to office task lighting, for example under-shelf luminaires.

Other instances of task lighting are in machinery, where a specific work area needs illumination, 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. 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.

Office task lighting

Localised average lighting

Localised average lighting consists of a luminaire that supplies 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.

Freely adjustable task light

The main feature of the freely adjustable task light is evident, you may adjust it freely at any whim or to suit your needs. The lamp presents few limits to how you 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.

Asymmetric task light

The asymmetric task light is intended to be placed at the side of the actual task. The luminaire directs the light obliquely over the desk, with the highest illuminance typically about 1' to 1½' to the side of the lamp head. It mostly has an arm system that holds the lamp head horizontally irrespectively of the arm movement; "parallel arm". Asymmetric lamps often cause more reflected glare than other lamps. In workplaces where people use different table heights, an asymmetric lamp may cause direct glare due to its absence of means for glare control ( [http://web.comhem.se/~u77479609/better_lamp.html#properly_glare_protected ref:1] ).

Contrast reduction

Contrast reduction in the office workplace refers to reading objects having decreased contrast compared to an estimated ideal contrast. If a lamp is placed so that printed letters reflect some of the light, their contrast against the paper background will decrease. This happens when a light source is reflected as in a mirror from the print into the eyes of the observer. A poorly placed lamp may render text illegible, regardless of illuminance level.


* [http://web.comhem.se/~u77479609/better_lamp.html The glare free lamp] , by Urban Domeij

Wikimedia Foundation. 2010.

Look at other dictionaries:

  • Task lighting — (task oriented lighting)   Lighting designed specifically to illuminate one or more task locations, and generally confined to those locations. [See California Code of Regulations, Title 24, Section 2 5302] …   Energy terms

  • Task Lighting —   Any light source designed specifically to direct light a task or work performed by a person or machine …   Energy terms

  • Lighting — Not to be confused with lightning. For other uses, see lighting (disambiguation). Low intensity lighting and haze in a concert hall allows laser effects to be visible …   Wikipedia

  • Automotive lighting — Blinker redirects here. For other uses, see Blinker (disambiguation). Not to be confused with Magneti Marelli company AL Automotive Lighting. For lights in seafaring and aviation, see navigation light. The lighting system of a motor vehicle… …   Wikipedia

  • Urban Lighting — is the science and art of lighting the public environment. The reason for lighting our urban environment has it s origin in the fact that our eyes are not adapted to seeing in the darkness and therefore we need light in order to travel safely… …   Wikipedia

  • Transform, clipping, and lighting — (T L or sometimes TCL) is a term used in computer graphics. DescriptionTransform is the task of converting spatial coordinates, which in this case involves moving three dimensional objects in a virtual world and converting the coordinates to a… …   Wikipedia

  • Architectural lighting design — is a field within architecture and architectural engineering that concerns itself primarily with the illumination of architecture, including academic/institutional, corporate, hospitality, monumental structures, residential, retail/entertainment… …   Wikipedia

  • Riverlife Task Force — The Pittsburgh Riverlife Task Force (Riverlife for short) is a nonprofit public private partnership established in 2000 to guide and advocate for the redevelopment of the riverfronts of the City of Pittsburgh, Pennsylvania. It is the largest… …   Wikipedia

  • Over-illumination — This cosmetics store has lighting levels over twice recommended levels[1] Over illumination is the presence of lighting intensity (illuminance) beyond that required for a specified activity. Over illumination was commonly ignored between 1950 and …   Wikipedia

  • Council House 2 — (CH2) General information Type Office Location Melbourne, Australia …   Wikipedia

Share the article and excerpts

Direct link
Do a right-click on the link above
and select “Copy Link”

We are using cookies for the best presentation of our site. Continuing to use this site, you agree with this.