Light Pipes are passive optical components that allow you to transmit light from an LED on your PCB somewhere else. They’re very useful in space-restricted applications, or in devices like routers with a lot of components that want to mount on the edge of your board, such as Ethernet connectors or power jacks.
Instead of wasting valuable space at the edge of your board on LEDs, consider using a light pipe to move the light from your LED to your panel regardless of where the LED itself is on your board.
Light pipes come in three main styles.
Rigid Vertical, meaning the pipe transmits light directly upwards from the LED it’s mounted to. This lets you extend an LED easily up past much taller components on the board to meet the top wall of your enclosure.
Rigid Right Angle, meaning the light pipe bends 90 degrees and transmits light parallel to the PCB. This lets you move light from an LED mounted behind board edge components such as connectors and power jacks to the panel without having to mount the LED on the edge of the board as well.
Flexible light pipes, as the name suggests, can bend and flex however you need them to, allowing you to route the light from your LED wherever it needs to go.
Since light pipes are non-conductive parts, soldering is not required to mount them. Most light pipes are panel mounted or press fit, making them easy to install.
Another advantage of using light pipes is that they allow you to change the location of your LED light on the panel without having to change the location of the LED itself on the board.
When selecting a light pipe for your project, you can focus on simple physical characteristics such as rigid vs. flexible, lens size and style, or mounting requirements. Light pipes have no polarization, frequency limitations, or any other electrical parameters you need to be aware of before making a decision.
If you are considering an optical fiber for short range data transmission, a Fiber Optic Light Pipe may be what you’re looking for instead.