Data Center Cabling Solutions
In this short video JT reviews common end face polishes of fiber optic connectors popular in data centers. PC, UPC and APC are covered - what the acronyms stand for and why they exist. Watch for more!



Hi, I'm Josh Taylor, product manager with CABLExpress. Today, we're going to talk about the different types of polish on fiber optic connectors.

The 3 most popular are PC, UPC, and APC. Some would say physical contact, ultra physical contact, and angle physical contact, while others would debate that it's ultra polish connector, and angle polish connector. Either way, it is about the polish.

The reason we have these different types of polish is about back reflection. I want to explain what back reflection is. Here's an illustration of 2 fibers mated together. Most of the time, you have the light goes through from one fiber to the next, as it should.

Sometimes, the light will bounce back. That's back reflection. Too much of this can shorten the life of the transceiver, and that can lead to down time. Nobody wants that. Back reflection is measured in db. As I've written down here, PC is 40 or better, UPC is 50 or better, and APC is 60 or better. Anything over 63, you're discounting photons. For most equipment, that's just irrelevant.

Here's an illustration of an APC polish. As you can see, it's cut at 8 degrees. They have to mate up together like that, and really the beauty of that is the back reflection doesn't bounce back to the transceiver.

You never want to mate an angle to a flat. That's why the industry is standardized on a green band to make sure that you're mating properly, because you never want to do this.

Thanks for watching. I hope you learned something. For more information, visit us on