How Does A Laser Printer Work? (An In-Depth Explanation)

Printing with high-quality text and graphics can be a hassle, but laser printers solve that for you. Not only that, but it presents a truckload of other benefits, such as affordability, minimal maintenance, and much more.

If you’re looking to learn all about how laser printers work and why you should have one in your home, then keep on reading because we’re here to fill you in!


If you find yourself needing to print out large quantities of pages at once, you may have experienced other printers jamming up or otherwise failing to give you what you need on time.

High quality multi function color laser printers can print surprisingly big volumes without any issues, no matter what the design/colors are. Moreover, the toner used in laser printers sticks and is fused to the paper with heat, so it doesn’t get all wet and messy like inkjet printer ink can.


Aside from being able to print large volumes, they are capable of doing so in a timely manner. We know lasers to be speedy, and that’s no exception here. The lasers these printers use move very quickly, making printing much faster. This is partly why printing a ton of pages at once doesn’t take all day to finish!

Overall Cost

While the upfront cost of the printer itself tends to be a bit steeper, you’ll likely end up saving money in the end. Laser printers use toner instead of ink so they are able to print more for less. Toners which print more for the same price as what a cartridge could do.

Noise Emission

We all know the whirring and clanking around printers tend to produce while in use. With laser printers, most times, there’s no noise at all! If the room you’re in is practically silent, then you may notice something but by no means is it distracting or annoying.

Less Maintenance

Inkjet printers regularly need a new cartridge or two and must be properly aligned to print the right way. The print heads regularly need cleaning and realignment, so you have to pay attention to this.

Not only that, but the ink can dry up in little components at times, which requires even more attention. In contrast, laser printers’ toners are simply replaced when needed, and that’s it!

Laser Printer Components & Parts

  • Imaging Unit, Drum, or Photoconductor Unit 
    Typically consisting of an aluminum cylinder with a light-sensitive film, the light bounced from mirrors creates an image on the drum.
  • Tone and Toner Cartridges 
    Toner is a very fine plastic powder of all colors, and when heated up, it transforms into ink. The cartridges each hold a different shade of toner powder.
  • Corona Wires 
    The primary corona charges the photosensitive particles on the outer part of the drum, while the transfer corona charges the surface of the paper before reaching the toner zone.
  • Fuser Unit 
    Usually consisting of 2 rollers, one is warmed up, melting the film of toner plastic to let the ink transfer onto the printer paper. The other is covered with a silicone coating and is made of soft rubber to hold the paper, making sure it moves smoothly between the rollers.
  • Laser Beams 
    This is controlled to shoot pulses of light at mirrors within the printer onto a photosensitive drum to create the images you want.
  • Driver and Software 
    Most will come with an array of software programs, including the drivers necessary for working with your OS, diagnostic programs, and more.
  • Power Supply 
    Laser printers should never be hooked up to a UPS device, as they demand higher voltages. It does include a low-voltage converter, however.

Understanding How A Laser Printer Works

Preparing and Storing Data

The document passes through the model’s communication port onto the Printer Controller Unit, converting the data into a binary dot pattern(s) which become stored in the Raster memory. Once this is done, the printer will determine from the 4 toner inks which should be used.

Charging the Photoreceptor/Photoconductor Drum

A rotating drum or belt covered in a photosensitive coating receives a positive charge or polarity by means of a corona wire or primary charge rollers (newer models only, usually). The rasterized data kept in the memory can now be streamed to a fixed-position laser.

Exposing the Image

Light photons given off from the laser move through a moving polygonal mirror, with the photons discharging points on the photoconductive drums, which belongs to the original document we referred to in the first point.

Each bitmap dot is equal to a laser pulse, where empty space means no pulse. This means you'll get an exact electrostatic copy of the data stored onto the positively-charged spots on the drum.

Developing the Image

Through the developer unit, the toner powder becomes positively charged, attracted to only the proper areas (the image), which are negatively charged on the drum's surface.

Transferring Image to Paper

The corona wire charges the paper with a negative charge even more powerful than the image on the drum, so the paper pulls the toner powder from the drum to create the perfect image on paper.

Fusing of Image to Paper

The Detac corona wire discharges the paper, while coated rollers make sure powder doesn’t stick to the drum and fuser assembly. The dry powder is then heated onto the paper with the use of rollers. The paper then moves through quickly to avoid becoming too hot.

Cleaning of Photoreceptor

Lastly, any excess charge on the drum is discharged, and a rubber blade cleans off any leftover toner which is moved into the waste toner compartment. Some models actually move excess toner into a developer unit to be used again, though this isn't normally the case.

Lasers Printers Vs. Photocopiers

The most notable difference between the two is the way the image is created on a photosensitive drum. A photocopier utilizes a light and lens to focus in on the original image, projecting onto the drum.

A laser printer uses a laser beam to scan each line on the drum, with most newer models using infrared solid-state laser diodes like what you’ll see used in CD players.

Printers use cartridges which does add to the cost of use, while photocopiers use solely toner. However, the more features, the more expensive the photocopier is.

Newer photocopiers are smart machines and can do their job without someone having to stand there and “babysit” it. Printers have to be hooked up to a device, whether by USB or Bluetooth.

If you’re just printing on the same size of paper, you’re probably better off with a laser printer. However, if you’ll be using various sizes of paper, you can do this with a photocopier – even with different sizes simultaneously!

Just remember that photocopiers don’t print, so if you print more than you duplicate, you’ll need a laser printer.

Lasers Printers vs. Photocopiers

People Also Ask (FAQs)

What do I do when the toner is running out?

First, go get some toner! Then, open the printer door so you can remove the drum assembly. Simply do this by pulling it straight out. Next, take out the used cartridge, pressing the level on the drum assembly.

Make sure you aren’t forcing it. Remove the new cartridge from its box, ensuring you don’t remove the plastic packaging. If you notice the toner is all settled to one side, gently shake the cartridge.

Next, take out the new one from the plastic, taking off all sealing tape. Make sure to avoid touching the imaging drum on the bottom. Snap the new cartridge into place. Once in place, move the drum cleaning lever back and forth and put the entire drum assembly back in, closing the printer's access port.

What steps should I take to maintain my laser printer?

Before you do anything, make sure you completely turn off and unplug your printer. We also recommend wearing a mask and latex gloves to protect yourself from toner particles. Make sure to do this in a well-ventilated area, free of wind, breeze, AC, fans, etc.

It’s best to follow what your printer’s manual indicates, so keep this handy and safe. Remove any dust and grime that may have built up on your laser printer as it can not only cause jams but can reduce the quality of printing. This is most easily done with canned air or a pressure-controlled vacuum.

Try to keep your printer updated with the latest drivers offered by the manufacturer. They’ll usually be accessible through their website. 

Is a laser printer better than an inkjet?

There’s not one that’s really “better” than the other: rather, they each have their own pros and cons. Laser printers are by far faster, less likely to jam up, and overall cheaper to use. However, inkjets are known to produce slightly better photos/color documents.

Do laser printers dry out?

Nope! Toner doesn’t dry out as it’s already a dry powder!

How long will a laser printer last?

Proper maintenance is crucial for extending the lifespan of your printer and the better your maintain it the longer it will last. In general though, you can expect your average model to last around 5 years.

Should I turn off the laser printer when not in use?

It’s really up to you. You will save a bit of electricity by turning it off when you aren’t using it, and some models also come with a nice power-saving mode that could be handy.

Do laser printers need special paper?

No, you can just use regular printer paper!

Are laser printers hazardous to health?

It’s been reported that laser printers can emit some toner particles into the air, though the quantity emitted is debatable. You’re better off sitting a reasonable distance away from it, though it isn't likely to negatively affect your health.


Now that you know all you need to about laser printers, have you decided to get one for yourself? They're machines that can really make work and art projects a lot easier, and we're sure you won't regret it.