LED Lens Design,Light Distribution, and Roadway Classifications

• What is the plastic covering over the LEDs?
  This is called the Lens or Optics. The optic lens will focus the LED to control the distribution of light. This allows us to provide different light distributions for
  different applications. We offer a variety of lenses to meet Type I –Type 4
  roadway patterns.

• How do I specify which lens I need?
  T Series (T3, T4), A Series(A2, A2M2, A3, A4)
  
  T series is a symmetrical lens, A series is an asymmetrical lens. The symmetrical lens will have the same luminance directed toward the road and off the road (to the rear of the streetlight). The asymmetrical lens will be more effective on the road side, and have less light shining off the road.

The difference between lens designs will be in the angle on the each side.
 

 Remarks:

• 35 feet
• H means the horizontal side, the same side of install the light
• V means the vertical side, which is the width of the road side
• Every beam pattern dimension is calculated based on the area which edge lux level reduced to the 10% of the center point lux level
• A series lens is asymmetrical kind of lens, so the vertical side will be calculate at the line where the light is installed
• * means the distance between road side edge of beam pattern to the light installation position

Type I: The Type I luminaire is placed in the center of the roadway or area where lighting is required. It produces a long, narrow, oval-shaped lighted area. Some types of high-mast lighting are considered a modified form of Type I.

Type II: The Type II luminaire is placed on the side of the roadway or edge of the area to be lighted. It produces a long, narrow, oval-shaped lighted area which is usually applicable to narrower roadways.

Type III: The Type III luminaire is placed on the side of the roadway or edge of the area to be lighted. It produces an oval-shaped lighted area and is usually applicable to medium width roadways.

Type IV: The Type IV luminaire is placed on the side of the roadway or the edge of area to be lighted. It produces a wider, oval-shaped lighted area and is usually applicable to wide roadways.

Type V: The Type V luminaire is located over the center of the roadway, intersection, or area to be lighted. It produces a circular, lighted area. Type V often is used in high-mast lighting applications.