Understanding Thermal Printers – CompTIA A+ 220-901 – 1.14

Thermal printers print with heat instead of ink or toner. In this video, you’ll learn how the internal components of thermal printers work together to create our printed output.

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On a thermal printer you are printing with heat. There’s no ink, there’s no toner, you never run out of either of those resources because all you have to do is heat the page, and the part of the page that you’ve heated will turn black.

Thermal printers are very quiet. You can have them in a very quiet workplace or in a library, and print to these printers and not worry about disturbing the people around. Unfortunately, this thermal paper is very sensitive to light and to heat. It’s not a type of paper you’re going to archive information over a long period of time. You also have to be careful about other chemicals, like the kind that you find on clear tape, that will also tend to fade and cause the information on these pages to disappear.

Thermal printers is going to have a feed assembly that’s going to grab the thermal paper and pull it across the printer head. This is one that has a bit of a rubberized coating on it, so it’s able to grip the paper and send it through the printing path. Here’s a picture of the feed mechanism on this thermal printer. The printer top is open so you can see the feed mechanism here the top. It’s got a geared control, and it has these rubberized coating along the outside, so that it’s able to grab the paper and pull it across the print head and through the printer.

The printing mechanism inside of a thermal printer is this heating element. It’s a full size heating element. There’s nothing that moves. It simply heats up the right part of that element to put information onto the thermal paper. Here’s a closer view of this. You can see that the output is coming out this printer, and it’s just being pulled across this print head. It’s heating up as the paper goes by.

Although you don’t need any special ink or toner to print on a thermal printer, you do need a special kind of paper. This paper is coated with a chemical that’s going to change color whenever it’s heated, and that’s how we’re able to get the output onto these pieces of paper. You usually see these on cash registers, or credit card terminals, or places where you need a very quiet printer to operate. This does look like normal paper, but if you feel it, it does feel a little bit different. You can feel the chemical coating on the outside of the paper. And that’s why you want to be sure you always have extra paper. Once you run out of thermal paper, you’re not able to print anything on that thermal printer.