Light Pipe Frequently Asked Questions

What is an LED Light Pipe?

An LED Light Pipe is a practical solution to conduct light from board-mounted LEDs to the exterior, or in some cases, a photo detector. Light pipes can be produced in either rigid or flexible constructions and can be designed to include right angle and vertical or horizontal packaging with either single or multiple pipes. Light pipes can enhance display quality and add greater flexibility to light distribution. The integration of an LED Light Pipe is a cost-effective option to help eliminate many of the varied, complicated steps otherwise required to transport light from one place to another.

 

What are the Attributes of a Light Pipe?

Although specific design considerations may vary, a standard Light Pipe construction is typically:

  • Optically clear for specified wavelengths
  • Made out of polycarbonate
  • Capable of being panel or PCB mounted
  • Compatible for use with either surface-mount or through-hole LEDs
  • Include an oval, round or rectangular lens cap in the display end

When Would You Use a Rigid Light Pipe?

Rigid Light Pipes are ideal if the LED is mounted on a board immediately behind a front panel. As their name implies, a Rigid Light Pipe is produced with a hard plastic material and will have either a vertical or a right-angle construction, capable of redirecting the LED’s light output to the desired location with minimal loss of intensity.

How Does a Flexible Light Pipe Differ From a Rigid Light Pipe?

Flexible Light Pipes function much the same as their rigid counterparts, however Flexible Light pipes are constructed of an optical fiber material that provides less rigidity allowing them to transport light from a board at custom, subtle angles.

What Are Some of the Design Considerations When Working with Light Pipes?

There are several design considerations to be examined working with light pipes:

  • The light pipe has to be designed in such a way that it captures the maximum possible amount of light from the LED without reflecting it away.
  • Having the light leave the light pipe in the desired location becomes the goal once the light has been captured. The light travels on a direct course within straight light pipes. More consideration needs to be given to effectively route light inside angled light pipes.
  • Working around objects can also present a challenge to a design. There are a variety of options available for working around objects which can be addressed through software modeling, such as Lumex’s Ray Trace Software.
  • Design the geometry to allow the light to escape through the exit surface with minimal loss.

Can Lumex Provide Display Uniformity?

Lumex’s LED Light Pipes can be configured at the output end with a variety of geometric emitting surfaces, such as an oval, round or rectangular lens cap to provide the exact display pattern desired.

What about Brightness Considerations?

Generally speaking, the brightness emitted will be dependent upon the LED utilized and the number of turns and shape of the light pipe. The ideal light pipe will emit the same brightness as the LED, minimizing the amount of light lost.

Does Lumex Provide Product Prototyping?

Lumex specializes in providing different configurations and creating special shapes to fit an exact requirement.

In addition, Lumex uses state-of-the-art Ray Trace Software with precise 3D CAD/CAM models to ensure proper design and optimal light transmittance, with minimal light loss. This advanced technology system helps to advance the design of the light directly from the LED(s) into the Light Pipe(s) to help eliminate many intermediate steps and ensure minimal light loss.