How does a laser printer work? Laser printing - basic principles of operation. How does a laser printer print?

In a printer based on laser printing technology, everything works through the use of static electricity. How it works? The laser beam hits the photodrum in the cartridge and forms an image. At the next stage of image formation, the photodrum comes into contact with the toner and the toner sticks at the point of contact where the laser shined and changed the charge. Using the same principle, toner sticks to the paper from the photodrum and is then baked in the so-called “oven”. The paper comes out warm from the stove. Don't be afraid, it's already cooled down a little.

Learn more about the laser printing process

When the photosensitive drum rotates, a positive charge is formed on its surface, which is applied to the photo roll using a laser beam. The positive charge attracts toner particles, which are negatively charged, and they stick to the surface of the drum.

The sheet of paper is positively charged and passes under a rotating photo roller during the printing process. The negatively charged toner particles are transferred from the drum to the sheet of paper, thus transferring the image onto the paper. Next, the toner, once on the paper, is fixed under the influence of heat.

Unlike printing on matrix and inkjet printers, where the image is transferred to paper line by line, with laser printing the text on an A4 sheet is formed in just 3 revolutions of the photodrum.

Laser printers are based on the printing system used in copiers. In copiers, a special lamp transfers the image from the sheet being copied to the photosensitive surface of the drum in the form of an electrostatic charge. The image drum converts the optical image created by light reflected from the copied image into its electrostatic equivalent, which attracts toner particles with the opposite charge to the surface of the drum.

However, a laser printer does not have an original image; instead, in its memory there is a matrix consisting of 1s and 0s that transmits the image. In the case of black and white printing, 1 transmits a signal to the microprocessor and directs the laser beam to the photodrum. When the beam touches the surface of the drum, a positive charge is formed at that location, and negatively charged toner particles will stick to the drum at that location. Accordingly, 0 does not transmit a signal and no charge appears on the surface of the drum, and later these areas will remain white on the paper. Read the article about how to get rid of white stripes when printing -

Includes seven sequential operations to create a given image on a sheet of paper. This is a very interesting and technological process that can be divided into two main stages: applying the image and fixing it. The first stage is associated with the operation of the cartridge, the second takes place in the fusing unit (oven). As a result, in a matter of seconds we get the image we are interested in on a white sheet of paper.

So, what happens in such a short period of time in the printer? Let's figure this out.

Charge

Let us remember that toner is a finely dispersed substance (5-30 microns), and its particles very easily accept any electrical charge.

In the cartridge, the charge roller ensures uniform transfer of negative charge to the photodrum. This happens when the charge roller is pressed against the photodrum, and rotating in one direction (while uniformly imparting a negative static charge to the photodrum), causes it to rotate in the other.

Thus, the surface of the photodrum has a negative charge evenly distributed over the area.

Exhibition

In the next process, the future image is exposed on a photodrum.

This happens thanks to a laser. When a laser beam hits the surface of the photodrum, it removes the negative charge in this place (the point becomes neutrally charged). Thus, the laser beam forms the future image according to the specified coordinates in the program. Exclusively in those places where it is necessary.

This way we get the exposed part of the image in the form of negatively charged dots on the surface of the photodrum.

Development

Next, toner is applied to the exposed image on the surface of the photodrum in an even thin layer using a developing roller. The toner particles take on a negative charge and form a future image on the surface of the drum.

Transfer

The next step is to transfer the negatively charged toner image from the drum to a blank sheet of paper.

This occurs when the transfer roller comes into contact with a sheet of paper (the sheet passes between the transfer roller and the image drum). The transfer roller has a high positive potential, causing all the negatively charged toner particles (in the form of an image formed) to be transferred to the sheet of paper.

Consolidation

The next step in laser printing is fixing the toner image onto a sheet of paper in a fusing unit (in the oven).

At its core, this is the process of “baking” onto paper. A sheet of toner, passing between a thermal roller and a pressure roller, is subjected to thermo-baric (temperature and pressure) treatment, as a result of which the toner is fixed on the sheet and becomes resistant to external mechanical influences.

In our picture you see a thermal shaft and a pressure roller. Thermal roll is used in a number of laser printing devices. A halogen lamp is used inside the thermal shaft, which provides heating (heating element).

There are other models of laser printing devices, where thermal film is used instead of a thermal roller (as a heating element). The difference between them is that the halogen heater takes longer to operate. It is worth noting the fact that devices with thermal film are very susceptible to mechanical influences from foreign objects (paper clips, staples from a stapler) on a sheet of paper. This is fraught with failure of the thermal film itself. She is very sensitive to damage.

Cleaning

Since during this whole process a small amount of toner remains on the surface of the photodrum, a squeegee (cleaning blade) is installed in the cartridge to clean residual microparticles of toner from the photodrum shaft.

As it rotates, the shaft is cleaned. The residual powder ends up in the waste toner bin.

Removing charge

During the last stage, the photodrum shaft comes into contact with the charge roller. This leads to the fact that the “map” of negative charge is again aligned on the surface of the drum (up to this point, both negatively charged places and neutrally charged ones remained on the surface - they were the projection of the image).

Thus, the charge roller again imparts a uniformly distributed negative potential to the surface of the photodrum.

This ends the cycle of printing one sheet.

Conclusion

Thus, laser printing technology includes seven successive stages of transferring and fixing an image onto paper. On modern devices, this process of printing one image on A4 paper takes only a matter of seconds.

When worn out internal parts, such as the photodrum, charge roller or magnetic shaft, are replaced. These components are located inside the cartridge, and you can see them in the picture above. Due to wear of these elements, print quality deteriorates significantly.

A little about the history of laser printing

And finally, a little about the development of laser printing technology. Surprisingly, laser printing technology appeared earlier, for example, the same matrix printing technology. Chester Carlson invented a printing method called electrography in 1938. It was used in photocopiers of that time (60-70s of the last century).

Directly the development and creation of the first laser printer Prescribed by Gary Starkweather. He was an employee of Xerox. His idea was to use copier technology to create a printer.

First appeared in 1971 first laser printer Xerox company. It was called the Xerox 9700 Electronic Printing System. Serial production was launched later - in 1977.

Color laser printers are beginning to actively conquer the printing market. If just a few years ago color laser printing was something unattainable for most organizations, and even more so for individual citizens, now a very wide range of users can afford to buy a color laser printer. The rapidly growing fleet of color laser printers is leading to growing interest in them from technical support services.

Principles of color printing

In printers, as in printing, it is used to create color images. subtractive color model, and not additive, as in monitors and scanners, in which any color and shade is obtained by mixing three primary colors - R(red), G(green), B(blue). The subtractive color separation model is so called because in order to form any shade, it is necessary to subtract “extra” components from the white color. In printing devices, to obtain any shade, the following are used as primary colors: Cyan(blue, turquoise), Magenta(purple), Yellow(yellow). This color model is called CMY by the first letters of the primary colors.

In the subtractive model, when two or more colors are mixed, complementary colors are created by absorbing some light waves and reflecting others. Blue paint, for example, absorbs red and reflects green and blue; purple paint absorbs green and reflects red and blue; and yellow paint absorbs blue and reflects red and green. By mixing the main components of the subtractive model, different colors can be obtained, which are described below:

Blue + Yellow = Green

Magenta + Yellow = Red

Magenta + Cyan = Blue

Magenta + Cyan + Yellow = Black

It is worth noting that to obtain black it is necessary to mix all three components, i.e. cyan, magenta and yellow, but getting high-quality black in this way is almost impossible. The resulting color will not be black, but rather a dirty gray. To eliminate this drawback, one more color is added to the three main colors - black. This extended color model is called CMYK(C yan- M agenta- Y ellow-black K – cyan-magenta-yellow-black). The introduction of black color can significantly improve the quality of color rendering.

HP Color LaserJet 8500 Printer

After we have discussed the general principles of the construction and operation of color laser printers, it is worth familiarizing yourself in more detail with their structure, mechanisms, modules and blocks. This is best done using the example of a printer. As an example, let's take the Hewlett-Packard Color LaserJet 8500 printer.

Its main characteristics are:
- resolution: 600 DPI;
- print speed in “color” mode: 6 ppm;
- print speed in “black and white” mode: 24 ppm.

The main components of the printer and their relative positions are shown in Fig. 5.

Image formation begins with residual potentials being removed (neutralized) from the surface of the photodrum. This is done so that the subsequent charge of the photodrum is more uniform, i.e. Before charging it is completely discharged. Removal of residual potentials is carried out by illuminating the entire surface of the drum with a special preliminary (conditioning) exposure lamp, which is a line of LEDs (Fig. 7).

Next, a high-voltage (up to -600V) negative potential is created on the surface of the photodrum. The drum is charged with a corotron in the form of a roller made of conductive rubber (Fig. 8). The corotron is supplied with a sinusoidal alternating voltage with a negative DC component. The alternating component (AC) ensures uniform distribution of charges on the surface, and the constant component (DC) charges the drum. The DC level can be adjusted by changing the print density (toner density), which is done using the printer driver or through adjustments through the control panel. An increase in negative potential leads to a decrease in density, i.e. to a lighter image, while decreasing the potential – on the contrary, to a denser (darker) image. The photodrum (its internal metal base) must be “grounded”.

After all this, a laser beam creates an image on the surface of the photodrum in the form of charged and uncharged areas. The laser light beam, hitting the surface of the drum, discharges this area. The laser illuminates those areas of the drum where the toner should be. Those areas that should be white are not illuminated by the laser, and a high negative potential remains on them. The laser beam moves across the surface of the drum using a rotating hexagonal mirror located in the laser assembly. The image on the drum is called a latent electrographic image, because it is represented as invisible electrostatic potentials.

The latent electrographic image becomes visible after passing through the developing unit. The black toner developing module is stationary and is in constant contact with the photodrum (Fig. 9).

The color developing module is a carousel mechanism with alternate supply of “color” cartridges to the surface of the drum (Fig. 10). Black toner powder is single-component magnetic, while colored toner powders are single-component but non-magnetic. Any toner powder is charged to a negative potential due to friction against the surface of the developing roller and the dosing squeegee. Due to the potential difference and the Coulomb interaction of charges, negatively charged toner particles are attracted to those areas of the photodrum that are discharged by the laser and are repelled from areas with a high negative potential, i.e. from those that were not illuminated by the laser. At any given time, only one color of toner is developed. During development, a bias voltage is applied to the developing roller, which causes toner to transfer from the developing roller to the drum. This voltage is a rectangular alternating voltage with a negative DC component. The DC level can be adjusted as the toner density changes. After the development process is completed, the image on the drum becomes visible and must be transferred to the transfer drum.

Therefore, the next step in creating an image is to transfer the developed image to the transfer drum. This stage is called the primary transfer stage. The transfer of toner from one drum to another occurs due to an electrostatic potential difference, i.e. Negatively charged toner particles should be attracted to the positive potential on the surface of the transfer drum. To do this, a positive bias voltage is applied to the surface of the transfer drum. direct current from a special power source, as a result of which the entire surface of this drum has a positive potential. When printing full color, the bias voltage on the transfer drum must constantly increase because After each pass, the amount of negatively charged toner on the drum increases. And in order for the toner to transfer and lay on top of the existing toner, the transfer voltage increases with each new color. This imaging stage is shown in Fig. 11.

During the transfer of toner to the transfer drum, some particles of toner may remain on the surface of the image drum and must be removed to avoid distorting the subsequent image. To remove residual toner, the printer has a drum cleaning unit (see Figure 17). This module contains a special shaft - a brush for removing the charge from the toner and the photodrum - this weakens the force of attraction of the toner to the photodrum. There is also a traditional cleaning squeegee that scrapes the toner into a special hopper where it is stored until the cleaning module is replaced or cleaned.

Next, the photodrum is charged again (after preliminary discharge), and the process is repeated until the image of the corresponding color is completely formed on the transfer drum. Therefore, the size of the transfer drum must fully correspond to the print format, i.e. in this printer model, the circumference of this drum corresponds to the length of an A3 sheet (420 mm). After applying toner of one color, the image formation process is completely repeated with the only difference being that a developing unit of a different color is used. To use another developing unit, the carousel mechanism rotates at a given angle and brings the “new” developing shaft to the surface of the photodrum. Thus, when forming a full-color image consisting of four color components, the transfer drum is rotated four times, and at each rotation a toner of a different color is added to the existing toner. In this case, yellow powder is applied first, then purple, then blue, and black powder is applied last. As a result, a full-color visible image is created on the transfer drum, consisting of particles of four multi-colored toner powders.

After the toner powder lands on the surface of the transfer drum, it passes through the additional charge unit. This block (Fig. 12) is a wire coroton, to which a sinusoidal alternating voltage (AC) with a negative direct component (DC) is supplied. With this voltage, the toner powder is additionally charged, i.e. its negative potential becomes higher, which will contribute to more efficient transfer of toner to paper. In addition, the additional voltage reduces the positive potential of the transfer drum, which helps ensure that the toner is positioned correctly on the transfer drum and prevents the toner from moving. The result is accurate reproduction of color shades. The additional charge voltage is supplied to the transfer drum during the application of yellow toner, i.e. at the very beginning of the image formation process. When applying yellow toner powder, the additional charge voltage is set to a minimum value, and after applying each new color, this voltage increases. The maximum boost voltage is applied while black toner is being applied.

Next, the full-color visible image from the transfer drum must be transferred to paper. This transfer process is called secondary transfer. Secondary transfer is carried out by another corotron, made in the form of a transport belt (Fig. 13). The toner is moved onto the paper by electrostatic forces, i.e. due to the potential difference between the toner powder (negative) and the secondary transfer corotron, to which a positive bias voltage is applied. Since secondary transfer occurs only after four rotations of the transfer drum, the corotron transfer belt must feed the paper only when all colors have been applied, i.e. during the fourth revolution, and until this point in time, the belt should be in such a position that the paper does not touch the transfer drum.

Thus, during image creation, the transport belt is lowered down and does not come into contact with the transfer drum, but at the time of secondary transfer it is raised up and touches this drum. The corotron transport belt is moved by an eccentric cam, which is driven by an electric clutch upon command from the microcontroller (Fig. 14).

During secondary transfer, a sheet of paper may be attracted to the surface of the transfer drum due to the difference in electrostatic potential. This may cause the sheet of paper to wrap around the drum, resulting in a paper jam. To prevent this phenomenon, the printer has a system for separating paper and removing static potential from it. The system is a corotron to which an alternating sinusoidal voltage with a positive constant component is supplied. The location of the corotron relative to the paper and transfer drum is shown in Fig. 15.

During the secondary transfer stage, some toner particles are not transferred to the paper, but remain on the surface of the drum. To prevent these particles from interfering with the creation of the next sheet and distorting the image, it is necessary to clean the transfer drum and remove any remaining toner. Cleaning the transfer drum is a fairly complex process. This procedure uses a special cleaning roller, image drum, and image drum cleaning unit. The transfer drum should not be cleaned continuously, but only after the secondary transfer, i.e. The cleaning system should be controlled similarly to the transfer corotron. While the image is being created, the cleaning system is not active, and when the toner begins to transfer to the paper, it turns on. The first cleaning step is to recharge the residual toner powder, i.e. its potential changes from negative to positive. For this purpose, a cleaning roller is used, which is supplied with an alternating sinusoidal voltage with a positive constant component. This roller is pressed against the surface of the drum during cleaning, and is folded back during image creation. The roller is controlled by an eccentric cam, which in turn is driven by a solenoid (Fig. 16).

The positively charged toner is then transferred to the image drum, which still has a negative bias voltage. And already from the surface of the photodrum, the toner is cleaned with a cleaning squeegee of the photodrum cleaning unit (Fig. 17).

The creation of a full-color image ends by fixing the toner on paper using temperature and pressure. A sheet of paper passes between two rollers of the fixing block (oven), is heated to a temperature of about 200 ºС, the toner is melted and pressed into the surface of the paper. To prevent toner from sticking to the fuser, a negative bias voltage is applied to the heating roller, causing the negative toner powder to remain on the paper rather than on the Teflon roller.

We examined the operating principle of only one printer from one company. Other manufacturers may use other principles of image formation and other technical solutions when constructing printers, however, all these solutions will be very close to those discussed earlier.

The operating principle of all laser printers is quite similar to the operation of photocopiers. Initially, a magnetized area is created on the paper, to which the toner (printing powder) is then attracted. Then, the sheet of paper goes into what is called an oven, where the powder is melted.

How a laser printer works

The operating principle of all laser printers is quite similar to the operation of photocopiers. Initially, a magnetized area is created on the paper, to which the toner (printing powder) is then attracted. Then, the sheet of paper goes into what is called an oven, where the powder is melted. Once the process is complete, the powder cools and hardens. Strictly speaking, this is how the finished image is obtained on paper.

Despite the relatively high cost, in comparison with inkjet, even representatives of the entry-level price level will make it possible to obtain, although black and white images, they will be of obvious high quality. At the same time, the printing speed cannot be compared either. As for maintenance, it is quite simple and unpretentious; in particular, refilling laser printer cartridges is quick and, most importantly, inexpensive.

Main advantages of laser printers

Today, laser printers are the most popular and in-demand office equipment, due to a number of reasons:

1. high print quality, incomparable to inkjet counterparts;
2. reliability and long term operation;
3. resource efficiency:

• refilling a laser printer is done several times less frequently than refilling/replacing cartridges in an inkjet printer;
• If not used for a long time, toner for laser printers does not dry out and become unusable;

1. available price policy(despite the fact that laser printers are somewhat more expensive than inkjet printers, their quality of work and long service life will more than pay for all costs);
2. high printing speed;
3. relatively large print volumes;
4. resistance of printed copies to water and sunlight;
5. low noise level during operation;
6. low cost of printing (about 5 kopecks per 1 sheet);
7. environmental friendliness and safety for the environment and the human body.

Technical specifications or how to choose a laser printer?

When deciding to purchase a laser printer, most users do not know technical characteristics, often make the wrong choice.

Due to the fact that a laser printer is capable of completely forming the image that is to be printed on the slug drum, it is extremely important to have a large amount of memory and a high-frequency digital processor. So, for a laser printer with black and white printing, the optimal memory size can be considered 4-8 MB, and for a color printer - from 32 MB. In modern printers, the memory capacity can be increased using additional modules.

As for the optimal processor frequency, it varies from 25 to 150 MHz. In turn, the acceptable print resolution is from 600 to 1200 dpi.

Laser printer resources allow you to print about 8-12 thousand copies in one calendar month. Also, when choosing a model, you should pay attention to the cartridge resource, which means the number of copies that can be printed without refilling.

Today it is difficult to imagine life without printing devices. From time to time it is simply necessary to transfer information to paper. Schoolchildren need to print out reports, students need to print out diplomas and coursework, and office employees need to print out documents and contracts.

There are several types of printers. They differ in the printing principle, the format of the paper used, the type of printed materials and other characteristics. Let's consider the principle of operation of two types of printing devices - laser and inkjet.

Working principle of an inkjet printer

First of all, let's look at how an inkjet printer works. It’s worth mentioning right away that in terms of print quality it lags slightly behind laser. However, the cost of an inkjet printer is significantly lower. This type The printer is perfect for home use. It is easy to handle and easy to maintain.
If we talk about the operating principle of laser and inkjet printers, they are radically different. The main difference is the ink supply technology, as well as the hardware design. Let's first discuss how an inkjet printer works.

The operating principle of this printing device is as follows: an image is formed on a special matrix, after which it is printed on a canvas using liquid ink. There is another variety inkjet printers, the device of which contains cartridges. Cartridges are installed in a special block. In this design, ink is transferred to the print matrix using the print head. After this, the matrix transfers the image onto paper.

Storing ink and applying it to the canvas

There are several ways to apply ink to canvas:

— gas bubble method;
— piezoelectric method;
— drop-on-demand method.

The piezoelectric method involves the creation of ink dots on the canvas using a piezoelectric element. The tube opens and contracts again, preventing excess ink drops from falling. The gas bubble method is also known as the injected bubble method. They leave an imprint on the canvas due to high temperatures. The nozzle of each printing matrix has a heating element. It takes a fraction of a second to heat up such an element. After heating, the resulting bubbles are transferred to the canvas through nozzles.

The drop-on-demand method also uses gas bubbles. However, this is a more optimized method. Print speed and quality have increased significantly.

Ink in an inkjet printer is typically stored in two ways. The first method involves the presence of a separate reservoir from which ink is supplied to the print head. In the second method, a special cartridge is used to store ink, which is located in the print head. To replace the cartridge, you will have to change the print head itself.

Using Inkjet Printers

Inkjet printers have gained particular popularity due to the fact that these devices have the ability to print in color. An image in color printing is created by superimposing basic tones with varying degrees of saturation on top of each other. The basic set of colors is also known by the abbreviation CMYK. It includes the following colors: black, cyan, purple and yellow. Initially, a set of three colors was used. It included all the colors listed above except black. But even when applying cyan, yellow and magenta colors at 100% saturation, it was still not possible to achieve black, the result was either gray or brown. For this reason, it was decided to add black ink to the main set.

Inkjet printer: operating features

The main indicators of printer performance are usually considered to be print speed, noise characteristics, durability and print quality. Let's consider the performance qualities of an inkjet printer.

The operating principle of such a printer has already been discussed above. Ink is supplied to paper through special printers. An inkjet printer operates very quietly, unlike, for example, needle printers, in which ink is applied through a mechanical impact process. You will not hear the inkjet printer printing; you can only hear the noise of the mechanism that moves the print heads. If we talk about the noise characteristics of inkjet printers in quantitative terms, then when such a device is operating, the noise level does not exceed 40 decibels.

Now let's talk about printing speed. An inkjet printer prints much faster than a pin printer. However, the quality of printing directly depends on such an indicator as speed. In this sense, the higher the printing speed, the worse quality. If you select High Quality Print mode, the process will slow down significantly. The paint on the canvas will be applied carefully. This printer prints at an average speed of 3 to 5 pages per minute. In modern printing devices, this figure has been increased to 9 pages per minute. Color images will take a little longer to print.

One of the main advantages of an inkjet printer is the font. In terms of the quality of font display, an inkjet printer can be compared, perhaps, only with a laser one. You can improve print quality by using good paper. The main thing is to choose paper that can quickly absorb moisture. High image quality can be achieved using paper with a density of 60 to 135 g/m2. Copier paper has proven itself well. Its density is 80 g/m2. To speed up the drying process of ink, some printing devices have a paper heating function. Despite the completely different operating principles of inkjet and laser printers, when using these devices it is possible to achieve the same quality.

Printing paper

An inkjet printer, unfortunately, is not suitable for printing on roll media. It is also not intended for making copies: you will have to use multiple printing.

Disadvantages of an inkjet printer

As mentioned earlier, inkjet printers print using a matrix. An image when printed on an inkjet printer is formed from dots. The most important and valuable element in the entire device is the print head. To reduce the size of the device, many companies integrate the print head into the cartridge. Inkjet and laser printers differ in their printing principles. The disadvantages of inkjet printers include the following:

1. Low speed printing;
2. Ink dries out after prolonged inactivity
3. High cost and short resource of consumables

Advantages of inkjet printers

1. Optimal price/quality ratio. When choosing a printing device, many users are most attracted by the price of this type of printer.
2. The printer has fairly modest dimensions. This makes it possible to mark it even in a small office or office. This will not create any inconvenience for the user.
3. Possibility to refill cartridges yourself. You can simply buy ink and read in the user manual how to refill it correctly.
4. Availability of a continuous ink supply system. This system will significantly reduce printing costs for large volumes.
5. High quality printing images and photographs
6. Large selection of printed media used

Laser printer

A laser printer today means a special type of printing equipment designed for applying text or images to paper. This type of equipment has a very unusual history. The principle of operation of a laser printing device began to be discussed only in 1969. Scientific research was carried out over several years.

To improve the operating principle of this device, many methods have been proposed. The world's first copying machine using a laser beam to create a print appeared in 1978. This device It was huge in size, and its cost was off the charts. Some time later, Canon took up this development.

The first desktop laser printer appeared in 1979. This led to other companies beginning to optimize and promote new models of laser printers. The principle of printing itself has not changed. Prints obtained using a laser printer have high performance. They are not afraid of fading or erasing, they are not afraid of moisture. Images produced using a laser printer are highly durable and of high quality.

How a laser printer works

Let us briefly describe the operating principle of a laser printer. An image when printed on a laser printer is applied in several stages. First, a special powder called toner melts under the influence of temperature. It sticks to the paper. After this, the unused toner is removed from the drum using a special scraper and moved to the waste storage tank. The surface of the drum is polarized by a coronator. An image is formed on the surface of the drum. The drum then moves along the surface of the magnetic roller, which contains the toner. Toner sticks to charged areas of the drum. The drum then comes into contact with the paper and leaves toner on it. Then the paper is rolled through a special oven, in which the powder melts under high temperature and sticks to the paper.

Color laser printer

The process of printing on a color printer differs from black and white by using several shades. By mixing these shades in a certain ratio, you can create primary colors. Typically, laser printers have their own compartment for each color. This is their main difference. Printing color images on such a printer occurs in several stages. First, the image is analyzed, after which the charge distribution is formed. Next, the same sequence of operations is carried out as for black and white printing: a sheet of toner is passed through an oven, where the powder melts and sets with the paper.

Advantages of laser printers

1. High printing speed
2. Image endurance and durability
3. Low cost
4. High quality

Disadvantages of laser printers

1. During operation, ozone is released. Print on a laser printer only in a well-ventilated area
2. Bulky
3. High power consumption
4. High price

Conclusion

Having analyzed the operating principle and main characteristics of inkjet and laser printers, we can say that the first type of device is more suitable for home use. They are affordable and small in size. Laser printers are more suitable for offices where large quantities of documents need to be printed.