How to clean encoder disks and linear strips

What is the best way to clean rotary encoder disks or linear encoder strips of small dust and particles? When it comes to our optical and transmissive encoders, the best option is probably to actually just leave things alone. Why is that? Our encoder modules use an LED and phased array instead of a single photo detector. That means that small imperfections — the kinds that you would expect to see from everyday use and handling of encoders — typically just get averaged out by the array. Furthermore, our LEDs operate in the infrared spectrum, which means they're less susceptible to physical obstructions than visible light.

If you're dead set on trying to remove dust or particles, we have a few suggestions on how to do it correctly:

Don't use water or any type of liquid.

Most of our optical encoders are transmissive and the disks/linear strips are on a mylar material that is developed much like photography. Water and cleaners can actually damage the printing on the disk and create more problems than the dust, specks and minor scratches.

If you're going to use air, make sure it isn't compressed.

Compressed air, whether that be hooked up to an air compressor or the kind that comes in a can could potentially dislodge the encoder disk from its hub, and the resulting misalignment will create far more of an issue than you would have had with the specks.

The best way to take care of disks and strips is through prevention.

We always recommend that people wear gloves or finger cots during assembly to further protect the disks and strips. This is one of the best ways to prevent fingerprints and exposure to dust and other particulates.

All this being said, if you see dust, dirt, fingerprints or minor imperfections on your encoder disk and are concerned that there may be an issue with performance, you have two options:

First, you can test your encoder much like we did in the video above and make sure your waveforms are acceptable.

Second, you are always more than welcome to send us a photo of your encoder disk.