The Magic Inside Canon Toner Cartridges
Canon laser printers leverage some amazing technological achievements to produce the printing performance that they do. If you could see the various components going on inside your Canon laser printer, it would be like a modern art piece in your home or workspace. Let’s see what makes the toner cartridge tick, on a tour through its inner workings.
The primary performer in a Canon toner cartridge is the photo-sensitive drum (PSD). This is a roller with a special coating that can hold very precisely-placed electrical charges. This is crucial for the production of a high resolution image, since the smaller the charged spots can be, the better resolution the PSD can deliver to the page.
Let’s start with the charging cylinder. This is another roller in the cartridge that is in constant contact with the PSD. Its function is to supply a uniform electrical charge to the surface of the PSD as it approaches the laser.
The laser, that gives this type of printing its name, is where the marvels of modern computing and precision really shine. A laser beam is shot at the PSD, leaving an area of charge opposite to the charge applied by the charging cylinder. These spots of charge are very small and the laser applies them in rows across the PSD as it rolls by, at crazy speeds upwards of thousands of spots per second.
The PSD now carries an image in the form of charged spots, and heads for the toner. The toner cylinder brings charged toner particles into contact with the PSD. The toner particles are given a charge opposite to the image that the laser laid down. This makes the toner electrically attracted to the image, leaving the PSD with a coating of toner particles on the image.
Next, is the actual “printing” step. The PSD finally comes into contact with a sheet of paper, and the toner particles are transferred onto the page. The paper then passes through fusion rollers, which squeeze the paper from both sides and apply heat at the same time. This fuses the toner particles to the paper, making the image permanent. Without this step, the toner particles will be loose and prone to smudging and image distortion.
From here the PSD is cleaned off by a blade, which very precisely removes any toner particles that may have stayed behind after coming into contact with the paper. This prepares the PSD for contact with the charging cylinder, where this whole process will start again.
The PSD continuously rolls during printing, with all of these stages taking place in order around the drum. This enables a Canon toner cartridge to apply an image in one smooth pass. With a dedicated toner cartridge for each colour, all carrying out this process continuously as a page rolls by, you get very speedy printing. This is why Canon laser printers can produce prints at such great speeds, and are a favourite of high paced office environments.