Communication from LED indication plays a critical role in virtually every device run by electricity, from consumer electronics to factory equipment, from semi-trucks to washing machines. LED indication lighting allows a device to communicate its status to the user. Product developers work hard to make that communication effortless. Their job as designers using LEDs for indication may not be as easy. That’s where light pipes come in.

Light pipes are designed to capture light from the LED and deliver it to the indication point. They provide a number of benefits that are able to not only improve performance but also simplify product development and manufacturing.

Greater board layout flexibility

Indication is a support function added to a board typically already filled with the electronics that serve the main purpose of the product. Being forced to position the LED next to the indication panel can be a major headache – other components may be occupying that space, the board may be oriented perpendicular to the indication panel, or there are heat-generating components in the area that would degrade the lifetime and performance of the LED. Light pipes remove that positioning constraint from the board layout.

With a light pipe, the LED can be placed perpendicular to the indication panel. It can be located a significant distance away from the indication point. With the assistance of fiber-optic flexible light pipes, the optical path can snake around obstacles, or indication lights can be added on multiple surfaces of the housing, in different orientations. Light pipes provide various options from flexible to rigid, ranging from 6 inches to 100 feet long, while LEDs can be as small as a grain of rice or as large as a piece of cereal.

Light bleed prevention

Devices with linear arrays of indicator lights can be challenging. LEDs might need to be spaced closely together, causing light to spill over from one to the next (optical crosstalk, also known as light bleed). Light bleed can particularly be an issue if the indicators are different colors or one needs to be off when the adjacent indicator needs to be on. Light pipes equipped with our ZeroLightBleed™ surface-mount adapter prevent light bleed for clear communication to the user. They are designed to fit over arrays of LEDs, reducing assembly to a single step.

More visually appealing designs

Purchasing decisions involve more than just performance and price. Particularly in the consumer space, aesthetics count. The dimensional options of rigid and flexible light pipes give designers the freedom to create the form factor that will attract users and best serve the application. Custom designs can create sleek new configurations that remain easy to assemble and reliable in operation.

EMI and ESD protection

Light is immune to EMI and ESD but LEDs and the electronics that drive and control them are not. Locating an LED next to an EMI source can cause problems, especially for devices with programmable output. Flexible light pipes provide a solution. Because light pipes are EMI immune, they can be used to separate the LEDs from EMI sources. In the case of ESD, light pipes can also protect devices and circuitry by adding distance between the user interface and the PCB.

Ease of assembly

In manufacturing, time is money. With the exception of IP-rated devices, most light pipes are press fit, for example, sliding into a crush ring in the front panel or snapping into predrilled holes in the PCB. Even IP-rated devices typically only require wrenches to ensure that retaining rings are tightened to spec.

These are just a few examples of ways that light pipes can help improve performance, enhance appearance and streamline assembly for a range of products. Learn more about light pipes and what they can do for your product roadmap. Contact the expert team at Bivar to get the process started.

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