19 Jun Which IESNA Light Distribution Is Right For Your Project?
To ensure the success of a commercial LED lighting project, the lighting professional needs to be able to choose reliable, high-quality LED fixtures that are within the project’s budget range. However, it is equally important that the selected fixtures can effectively deliver consistent light coverage, providing safety and visibility. The light distribution pattern varies between different types of fixtures, so all lights are not equally suitable for every application – for example, a LED area light that distributes light evenly on all sides will not work for a project requiring strict control of light spillover. For the best results, it is important to choose fixtures with the light distribution that is the most efficient for the required application.
The Illuminating Engineering Society of North America (IESNA) defines 5 distinct types of light distribution, providing a consistent standard for evaluating the light distribution patterns of different fixtures even across different manufacturers. Many commercial outdoor fixtures, such as roadway lights, area lights, and flood lights, are available in a range of light distribution types in order to accommodate a variety of lighting requirements, and larger commercial lighting projects will often require a mix of lighting distributions to ensure optimal lighting control and coverage.
Type I
A fixture with a Type I light distribution emits a very wide, symmetrical linear light pattern, with a large amount of light on both sides of the fixture. The width of a Type I light distribution pattern will be equal to the mounting height of the fixture. Type I fixtures are intended to be placed in the center of a pathway, and are ideal for lighting sidewalks and walkways. No GKOLED fixtures currently use a Type I distribution pattern.
Type II
A fixture with a Type II light distribution emits a wide oval light pattern, and is able to light up an area that is up to 1.5 times wider than its mounting height. Type II fixtures are intended for installation on a ramp or at the edge of a wide path or street. Our series GKORL01 LED Roadway Lights are available in a Type II distribution by special request.
Type III
Also commonly called Bat Wing distribution. A fixture with a Type III light distribution emits an oval light pattern with more forward throw but less width than Type II. The width of a type III distribution pattern is approximately 2.75 times wider than the fixture’s mounting height. This light distribution is often used for roads and exterior parking lot lighting. This is the default light distribution for our Tier 1 and Tier 2 LED Area Light fixtures and our series GKORL01 LED Roadway Light fixtures, and is also available by special request for our Tier 1 and Tier 2 LED Flood Lights.
Type IV
Fixtures with a Type IV light distribution are also commonly known as Forward Throw or Asymmetric fixtures. A fixture with a Type IV light distribution emits an oval light pattern with more forward throw but less width than Type III. Because of its minimal backlight, this light distribution is ideal for applications where it is important to control light spillover, such as building exteriors and parking area perimeters. This light distribution is available by special request for our Tier 1 and Tier 2 LED Area Lights, Tier 1 and Tier 2 LED Flood Lights, and series GKORL01 LED Roadway Lights.
Type V
A fixture with a Type V light distribution emits light equally and evenly on all sides, in a symmetrical square or circular pattern. GKOLED Type V fixtures are designed to emit a square light pattern, as it delivers more efficient light coverage. Type V fixtures are intended to be installed in the center of an area to be lit, and are commonly used for large commercial parking areas. This is the default light distribution for our Tier 1 and Tier 2 LED Flood Lights, and is also available by special request for our Tier 1 and Tier 2 LED Area Light fixtures.
To ensure effective, consistent illumination for an area being lit, it is important to carefully plan out every commercial LED lighting project in advance with a lighting layout. If you are unable to create one yourself, our engineers can make one for you, as well as recommend the optimal fixtures to use in your project. Contact us at 630-793-9449 or at info@gkoled.com for more information.