Types of printers. Types of printers: principles of operation, pros and cons of various types of printing

Today it is quite difficult not to get confused about what types of printers stores offer, because there are a lot of manufacturers, models and brands. However, the choice must be made responsibly, comparing technical characteristics various devices, because the purchase is not made for one year.

What are they?

So, you've decided to buy your own printer, but you don't know what types of printers there are or how to make your choice. Initially, it may seem that this is not such a simple task, and your eyes literally run wild, trying to simultaneously cover many different models, types and brands, which also have absolutely incomprehensible descriptions and a number of different parameters. However, in fact, all these difficulties are noticeable only at first glance, and the main thing you need to know is what types of printers there are.

Today, stores offer the following types of printers:

• matrix;
• jet;
• laser

The category of photo printers, specialized for performing certain tasks for which a standard printer cannot be used, also deserves special attention. The type of information in such printers is various images, photographs, etc.

Matrix

These are the oldest printers among all those existing today, as a result of which they are almost impossible to find in modern stores. They are significantly inferior in their characteristics to other types of printers, so it makes sense to compare only inkjet and laser devices, including photo printers.

Such devices print using a needle print head, which hits the paper through a special ink ribbon. Nowadays, due to the huge number of shortcomings, such printers can rarely be found anywhere, but they are still used at the ticket offices of railway stations and airports.

Disadvantages of dot matrix printers

• Enough low speed print.
• Noisy work.
• Extremely low print quality.
• Many restrictions in terms of color printing.

Advantages of dot matrix printers

• The cheapest among all consumables.
• Printing is carried out on almost any paper, which also expands the possibilities of using printers.
• Quite cheap mass printing on multilayer forms, which is why these types of printers are used for printing airline tickets.

Inkjet printers

These printers print by spraying ink onto paper through incredibly fine nozzles in the print head. Today you can purchase both color and black and white printers. of this type. Quite often, these types of printers provide the ability to print only in black and white inks, but it is possible to use color ones.

The cost of such printers is also relatively small, but another problem arises here - the rather high cost of original consumables. Types of inkjet printers practically do not differ from each other, therefore they have the same advantages and disadvantages.

Disadvantages of Inkjet Printers

• In order to ensure complete color printing When using the main types of inkjet printers, you need fairly thick or high-quality paper, otherwise the ink may simply bleed.
• The ink will take some time to dry after printing, which can ruin the printout if you accidentally touch it with your hand. And if you accidentally spill water on a sheet that was printed with an inkjet printer, then the image will be completely damaged.
• Minimum print speed compared to printing on a specialized laser printer.
• The print head may dry out. This moment is the most important, especially if at this moment the print head is located directly in the printer itself. If you do not use the printer for a long time, then the ink will begin to dry out and create a blockage in the nozzles, and the head may dry out so badly that the printer will have to be thrown away.

Benefits of Inkjet Printers

• The price of the devices themselves. They are quite cheap compared to laser printers, and if we consider the speed of black and white printing, the difference is almost insignificant.
• Possibility of color printing.
• The noise when printing is almost unnoticeable to others.
• Possibility of additional cartridge refilling. If your print head is located directly in the cartridge, then you can simply refill it instead of buying new ones.

Regarding the last point, it is worth noting that not all types of printer cartridges can be refilled in this way. In this regard, it is better to know in advance whether you have the possibility of standard refueling or whether you will have to constantly buy new components.

What types of print heads are there?

The first option is when the print head is located directly on the cartridge itself. This option is, in fact, disposable, but in the majority of cases it can easily withstand up to three refills, and its cost is often quite high, and for this reason it is best to refill the ink tanks several times before carrying out complete replacement cartridge for a new one.

However, refilling may cause some complications, including certain changes in print quality, as well as print head clogging or even printer failure. And if you're in in this case If you didn’t use original materials and used non-original types of printer ink, no one will fix your equipment under warranty.

The undeniable and main advantage of this cartridge is that if the print head dries out, it is quite enough to simply replace the cartridge to get your printer back into working condition.

The second option is when the head is located directly in the printer itself, and when replacing the cartridge, only the ink tank is replaced, which is much cheaper. However, in this case, you will need to monitor the condition of the print head much more carefully, because if the paint dries out in it or severe clogging occurs, then in this case you can completely throw away your printer, since the cost of repairing it will simply be incommensurate with the price of a new one devices.

It is for this reason that you will just need to turn on the printer at least once a week, since when it is turned on, it begins to prepare the head for work, pushing paint through the nozzles. By constantly buying new original cartridges, you may be able to increase the longevity of your print head, since you will eliminate the possibility of its clogging, but in this situation, printing will become very, very expensive.

A huge advantage of inkjet printers is the ability to use specialized refillable cartridges or a continuous ink supply system, which makes printing costs much cheaper.

Laser printers

The printing principle used various types laser printers are approximately the same as standard copiers - a specialized printing drum is used, but instead of lamp light there is a laser beam. The image in this case is formed by transferring a specialized powder toner to paper, which is then melted, passing through separate rollers, and finally fixed on the surface of the paper.

Types of printers and their characteristics may be different, but there are only two main varieties - color or black and white, however, it is worth noting that color devices are still quite expensive today, including both the cost of the device itself and the price of subsequent printing on it, as a result of which the purchase of such devices is advisable only if a person is engaged in professional color printing on a large scale.

Thus, the only significant disadvantage of a laser printer is that, in principle, it makes sense to buy it exclusively for black and white printing, and the very use of this printer is quite expensive, especially if the device includes a “refill protection” function.

What other disadvantages do laser printers have?

• The cost of the device, especially if the device does not have protection against refilling cartridges.
• In some cases, it is necessary to update the printer's firmware in order to be able to refill the cartridge. But in this situation you will completely lose the right to receive warranty service, and the cost of the firmware itself is quite high, and therefore this option becomes not very relevant, and it would be more profitable for you to buy a device that does not initially have such protection.

Advantages of laser printers

• Extremely high printing speed - the image is applied almost instantly.
• Ideal image quality regardless of what ink is used for printing in each specific case.
• Reliability of the resulting image. In other words, even if after printing the sheet accidentally water will get in, you will not see any negative consequences regardless of what types of printer paper you use.
• Almost silent operation.
• Relatively low cost of consumables. First of all, given the low price of the cartridge itself, it is quite enough to print enough large number images, and if necessary, the cartridge can be refilled or restored by changing various elements inside it.

Photo printers

Photo printers are devices that are somewhat different from what most people think of as "printers." The types (purpose) of such devices can be very different, but first of all they are used to print color images of the highest quality, including all kinds of posters, photographs or postcards. In other words, it's more professional equipment, the use of which in domestic and residential premises is inappropriate.

The printing principle used here is as follows: a specialized tape is pressed against the paper and gradually heats up, after which the dye applied to the tape begins to penetrate directly into the polyester coating of the paper. Such devices have a slightly higher cost compared to conventional inkjet devices, but their consumables are quite low in price.

Among other things, there are also different types of 3D printers, but they have nothing to do with printing on paper at all.

How to choose?

Printers should be selected according to your needs and financial capabilities. The characteristics are as follows:

• permission;
• print speed;
• processor and memory capacity;
• connection interface;
• support for various operating systems(more relevant for older types of printer);
• printing characteristics, as well as various additional parameters.

It is worth noting that the quantity and color of inks in the cartridge also deserve special attention if you are going to choose color inkjet printers. In addition, it is quite important to take into account the resource in the pages of the cartridge.

Among other things, be sure to consider both the cost of the device itself and the cost of subsequent use. In particular, the last parameter includes the price of cartridges, which may be original or non-original. Also pay attention to the cost of refills, consumables and paper that will match your device.

Hello.

I don’t think I will open America by saying that a printer is an extremely useful thing. Moreover, not only for students (who simply need it to print coursework, reports, diplomas, etc.), but also for other users.

Nowadays you can find various types of printers on sale, the price of which can differ tens of times. This is probably why there are a lot of questions regarding the printer. In this short reference article, I will look at the most popular questions that I get asked about printers (the information will be useful for those who are choosing a new printer for their home). So…

The article has omitted some technical terms and points in order to make it understandable and readable for a wide range of users. Disassembled only current issues users that almost everyone encounters when searching for a printer...

1) Types of printers (inkjet, laser, matrix)

Most questions come about this. True, users do not ask the question “types of printers”, but “which printer is better: inkjet or laser?” (for example).

In my opinion, the easiest way to show the pros and cons of each type of printer is in the form of a plate: it turns out very clearly.

My conclusions:

1. If you are buying a printer for printing photos, it is better to choose a regular inkjet printer (preferably a model on which you can later install continuous supply ink - relevant for those who will print a lot of photos). An inkjet printer is also suitable for those who occasionally print small documents: abstracts, reports, etc.
2. A laser printer is, in principle, a universal machine. Suitable for all users, except those who plan to print high-quality color pictures. A color laser printer is inferior in photo quality (today) to an inkjet printer. The price of the printer and cartridge (including its refill) is more expensive, but in general, if you make a full calculation, the cost of printing will be cheaper than with an inkjet printer.
3. Buying a color laser printer for the home, in my opinion, is not entirely justified (at least until the price drops...).

Important point. Regardless of what type of printer you choose, I would also check one detail with the same store: how much does it cost? new cartridge for this printer and how much it costs to refill it (refillability). Because the joy of the purchase may disappear after the ink runs out - many users will be very surprised to learn that some printer cartridges cost as much as the printer itself!

2) How to connect the printer. Connection interfaces

The vast majority of printers that can be found on sale support USB standard. As a rule, there are no connection problems, except for one subtlety...

I don’t know why, but often manufacturers do not include a cable with the printer to connect it to the computer. Sellers usually remind you of this, but not always. Many novice users (who are encountering this for the first time) have to run to the store 2 times: once to get a printer, the second to get a connection cable. Be sure to check the package when purchasing!

Ethernet

If you plan to print to a printer from several computers on a local network, you may want to opt for a printer that supports an Ethernet interface. Although, of course, this option is rarely chosen for home use, more It’s important to get a printer with Wi-Fi or Bluetooth support.

The LPT interface is now becoming less and less common (it used to be a standard (very popular interface)). By the way, many PCs are still equipped with this port to be able to connect such printers. There is no point in looking for such a printer for your home these days!

Wi-Fi and Bluetooth

Printers are more expensive price category often equipped with Wi-Fi and Bluetooth support. And I have to tell you - the thing is extremely convenient! Imagine walking around your apartment with a laptop, working on a report - then you press the print button and the document is sent to the printer and printed out in a moment. In general, this add. The option in the printer will save you from unnecessary wires in the apartment (although it takes longer for the document to be transferred to the printer - but in general, the difference is not so significant, especially if you are printing text information).

3) MFP - is it worth choosing a multifunctional device?

Recently, MFPs have been in demand on the market: devices that combine a printer and a scanner (+ fax, sometimes also a telephone). These devices are extremely convenient for photocopies - you put a sheet of paper and press one button - the copy is ready. As for the rest, I personally don’t see any big advantages (having a separate printer and scanner - you can remove the second one altogether and take it out whenever you need to scan something).

In addition, any normal camera is capable of taking excellent photos of books, magazines, etc. - that is, practically replacing a scanner.

HP MFP: scanner and printer complete with automatic sheet feeder

MFP advantages:

Multi-functionality;

Cheaper than buying each device separately;

Quick photocopy;

As a rule, there is an auto-feed: imagine how much easier this will be if you are copying 100 sheets. With automatic feeding: loaded the sheets into the tray, pressed the button and went to drink tea. Without it, each sheet would have to be turned over and placed on the scanner manually...

Disadvantages of MFPs:

Bulky (relative to a conventional printer);

If the MFP breaks, you will lose both the printer and the scanner (and other devices) at once.

4) Which brand should I choose: Epson, Canon, HP...?

There are a lot of questions about the brand. But here it is impossible to answer in monosyllables. Firstly, I would not look at a specific manufacturer - the main thing is that it is a well-known manufacturer of copiers. Secondly, it is much more important to look at the technical characteristics of the device and reviews of real users of such a device (in the age of the Internet - this is easy!). It’s even better, of course, if you are recommended by a friend who has several printers at work and sees the work of each one with his own eyes...

Name some specific model- even more difficult: by the time you read the article, this printer may no longer be on sale...

That's all for me. I will be grateful for additions and constructive comments. All the best :)

One of the purposes of a computer is to create a printed version of a document, or a so-called hard copy. This is why a printer is an essential computer accessory. However, this does not mean that every computer must come with a printer.

Thanks to the ubiquity local networks one printer can serve several users.

Scanners are most often used in the art departments of companies, but they can also be used at home.

Currently, there are a large number of printers on the market that have the most various characteristics. The criteria for choosing a particular printer will also be described. We will look at the basics of printing technology, types of printers and their functionality.

Printing technologies

Today there are three main printing technologies.

Laser. A laser printer works as follows: an electrostatic image of a page is created on a photosensitive drum using a laser beam. When placed on the drum, a specially colored powder called toner “sticks” only to the area that represents the letters or image on the page. The drum rotates and presses against a sheet of paper, transferring toner to it. After fixing the toner to the paper, the finished image is obtained. Similar technology is used in photocopiers.

The so-called LED printers produced by Okidata and Lexmark work similarly. But instead of a laser, they use an array of LEDs.

Inkjet. In inkjet printers, ionized ink droplets are sprayed onto the paper through nozzles. Spraying occurs in those places where it is necessary to form letters or images.

Point Matrix. Dot matrix printers use a group of round needles that strike a sheet of paper through an ink ribbon. These needles are arranged in a rectangular grid called a matrix. When certain needles are pressed, different symbols or images are formed in the matrix.

Laser printers provide the best print quality, followed by inkjet and then matrix. The price of laser printers is constantly decreasing, so they are becoming available to a wide range of users. Recently, inkjet and matrix printers have become more specialized: inkjet printers are becoming the main devices for color printing, as well as for the market, and matrix printers are intended mainly for ultra-fast and inexpensive printing (for example, in a bank or in a store for printing receipts).

Today, laser or inkjet printers are used almost everywhere, with the exception of specialized areas. This chapter covers the basics of printing technology found in different types of printers.

Permission

The term resolution is used to describe the contrast and quality of a printed sample. In all of the printing technologies discussed, an image is created by reproducing dots on paper. The printer resolution, and therefore the print quality, depends on the size and number of these dots. When viewing a page printed at low resolution on a dot matrix printer, the naked eye can see a pattern of dots forming characters. This is because the dots are quite large and uniform in size. And when viewing a page printed from high resolution on a laser printer, the characters have a "solid" appearance because the dots are much smaller and typically vary in size.

Printer resolution is usually measured in dots per inch; in other words, it is the number of individual dots a printer can print on a one-inch line. In most printers, resolution is determined in two directions - vertical and horizontal. Thus, 300 dip resolution means 300x300 pixels per square inch. A 300 dip printer can print 90 thousand dots per square inch of paper. There are printers that have different resolutions in two directions (for example, 600x 1200 dip). Such a printer can print 720 thousand dots per square inch.

It is important to understand the difference between printer and monitor resolutions. The term resolution in PC monitors refers to the number of pixels, for example 640x480 or 800x600. If you convert this resolution to a “printer” standard, you get 50-80 dip. Measuring actual size image (length and width) on the monitor screen and comparing it to the number of pixels, you can calculate the monitor resolution in dots per inch.

Therefore, you should not take WYSISWYNG (What YouSee IsWhat You Get) technology literally. The lowest resolution printer will print more dots than will be displayed on the monitor.

Each of the three main types of printers uses different methods of creating images on paper and different materials: powder toner, liquid ink or ribbon. The following sections will discuss how each type of printer creates an image on paper.

Laser printers

The process of printing a document on a laser printer consists of next stages: connection; data processing; formatting; rasterization; laser scanning; toner application; fixing the toner.

Different printers perform these steps in different ways, however, most printers perform exactly this sequence of actions. For example, inexpensive printer models use a computer intensively in the printing process, while more expensive and advanced models perform most of the operations using their own hardware and software.

LED Printers

These printers were developed by Okidata and appeared on the market as an alternative to laser printers. Both types of printers use the same principles to create an image on paper, except for the device used to neutralize the light-sensitive drum. Laser printers do this using a laser, while LED printers (as the name suggests) use an array of LEDs.

In terms of performance and print quality, LED printers are not inferior to similar models of laser printers. They are sometimes called "laserless laser printers" and are produced by Okidata and Lexmark.

Inkjet printers

The data interpretation processes for inkjet and laser printing are essentially similar. The only difference is that inkjet printers have less memory and less power. computer system. It is this difference that places them in the category of devices of a lower class and cost. Reducing the memory installed in the printer leads to the fact that such printers use strip buffers instead of whole page buffers. However, there are older models of inkjet printers, which have a memory capacity and computing power no lower than that of laser printers.

The main difference between inkjet and laser printers relates to the process of creating an image on a sheet of paper. The technology used in inkjet printers is much simpler than laser printers; it requires less expensive materials. Instead of a complex process in which toner is placed on a drum and then transferred to paper, inkjet printers spray liquid ink directly onto the paper - where a laser printer creates an array of dots. Simplification of the printing process makes application of the technology almost ideal inkjet printing in portable printers.

There are currently two main types of inkjet printing: thermal and piezoelectric. These terms describe the technology of spraying ink from a cartridge through nozzles. The cartridge consists of a reservoir of liquid ink and small (about one micron) holes through which the ink is pushed onto the paper. The number of holes depends on the printer resolution and can range from 21 to 256 (or more) per color. Color printers use four (or more) reservoirs of different color inks (cyan, magenta, yellow, and black). By mixing these four colors, almost any color can be produced. Some printer models use one cartridge with three reservoirs of color ink (cyan, magenta, and yellow).

Portable printers

Portable printers use two different technologies to create images on paper. Citizen models use shockless thermal technology using a special ink ribbon and a 60-cell print head. The main disadvantage of these printers is the limited resource of the ink ribbon: 30 black and white pages or 5 color, as well as low resolution - a maximum of 360 dpi. Portable printers from Canon and Brother are miniature copies of conventional desktop inkjet printers and provide a resolution of 720 dpi and a cartridge yield of several hundred pages.

Dot matrix printers

A few years ago, dot matrix printers were the most popular due to their small size, low cost and fairly high reliability. However, after prices for laser printers dropped and inkjet printers appeared, the market for dot matrix printers began to decline catastrophically. While they still do their job well, they are noisy, produce poor quality prints, and often jam paper.

Dot matrix printers, unlike laser and inkjet printers, do not create a document page. In a dot matrix printer, paper is placed in a vertical tray and moved line by line using rollers. The print head moves horizontally along a special guide and contains a matrix of metal needles (most often consisting of 9 or 24 needles) that extrude the image onto the paper. Between the needles and the paper there is an ink ribbon, like on a typewriter. The needles (through the tape) create a series of small dots on the paper, thus forming an image. When printing graphic images It is impossible to achieve high quality with dot matrix printers, so such printers are mainly used for printing text documents.

On almost all dot matrix printers, when printing, you can use both separate sheets and paper rolls

The only place where dot matrix printers have not yet lost ground is in banks and the retail sector.

Color printing

A color printer is becoming an essential attribute of a professional designer, artist or constructor. The simplification of inkjet printing technology has led to the fact that almost all manufacturers began to produce inexpensive models of color printers, aimed mainly at the home and office computers.

With most color printers, you can't simply mix colors to get the color you want, like an artist mixes paints. Instead, the printer prints the colors separately. For example, an inkjet printer prints a pattern of non-overlapping dots in which each dot is printed in a separate color. The number of dots of the same color in the pattern determines the resulting color. The process of creating a specific color is similar to creating an image on a monitor screen: three separate points - red, green and blue pixels - are used to create the desired color.

The resolution of some color printers is not sufficient to obtain a high-quality image. When printing on such a printer, you can see individual dots. The cumulative effect (individual points of the image merge into a single picture) appears only when viewing the printed image at a relatively large distance from the eyes: individual points are noticeable up close.

Color printing requires a complex language to communicate between the printer and computer.

Despite color support in the major page description languages, many printer manufacturers use their own technologies (producing their own drivers).

Currently, many programs have been created that can perform color printing. The true test of any printer is printing photos. For example, when printing charts from a spreadsheet program, you can use almost any color, which cannot be said about reproducing a photograph with natural colors. Some printers use six colors instead of four to produce high-quality photographic prints. If you want to get the print quality of an illustrated full-color magazine, then an inkjet printer will be powerless here. In this case, other printing methods are necessary.

When comparing color and monochrome printing, two important parameters are used: printing speed and cost. For color printers, slower print speeds provide more high quality. This statement can be applied to most inkjet printers. Therefore, always separate color and monochrome print jobs on your inkjet printer. Then, for example, the User will not have to wait until full-color presentation material is printed to print a one-page letter. The cost of color printers ranges from several hundred to several thousand dollars. However, there is another aspect to printing costs: the cost of supplies. With monochrome printing, one ink or toner cartridge is enough to print several thousand pages. At the same time, the cost of the cartridge is relatively low.

The situation is different with color printing. Most often, the cost of a color image is much higher than a monochrome one. Sometimes a printer requires special, more expensive types of paper. In addition, color ink or toner cartridges are more expensive. The cost of printing a page also depends on the number of colors used, for example printing a photograph will cost much more than printing a diagram.

Now let's move on to consider existing color printing technologies.

Printers with “solid” ink

There are "solid" inkjet printers that use solid inks instead of liquid ink. Such models are produced by Tektronix (a division of Xerox). During the printing process, the core melts and the ink is transferred to the drum and from it to the paper. In such printers, the image is created in the same way as in monochrome laser printers. The main difference between “solid” inkjet printers and color laser printers is the presence of only one drum for creating an image, i.e. All colors of the image are created on one reel.

Thus, the printing speed increases four times, and in addition, the print quality improves.

During the “solid-jet” printing process, paper is not subject to heat and high humidity, so you can use more inexpensive types of paper. In addition, servicing such printers is much easier.

Color sublimation printers

Color sublimation (or thermal color transfer) is a printing technology that uses a ribbon of four inks that are heated to a near-gas state by the printer. Before applying to paper, the paints are mixed to form the desired color. These types of printers can produce 256 shades of each of the four colors; Thus, the color palette reaches 16.7 million colors. As a result, such a printer can produce photographic print quality.

Despite their excellent print quality, dye-sublimation printers are slow, expensive, and require a special type of paper. In addition, we should not forget about the cost of the cartridge! Color sublimation printers are compatible with thermal wax printers, although this is entirely different technologies color printing. Some printer manufacturers produce models that support these two technologies. This allows the use of thermal wax technology (which is less expensive) for everyday printing, and color sublimation technology for final or other high-quality printing.

Thermal wax printers

These printers use wax-based ink, similar to solid ink. They must be melted before applying to paper. This printing process is faster than sublimation printing, and it does not require special grades of paper. Printers of this type differ from other inkjet printers in their higher print quality.

In some portable models The company's printers use a variation of the wax-based ink melting process. They use a regular head, like a dot matrix printer, and an “ink” ribbon (separate for rough and final printing).

Selecting a Printer Type

There are thousands of printer models on the market, so finding the model that suits your needs can be time consuming. In addition to price, there are other criteria by which you can choose a printer.

The printing speed of laser and inkjet printers is measured in pages per minute, while dot matrix printers are measured in characters per second. Increasing print speed and resolution increases the cost of the printer. For home printer Printing speed is not particularly important, while for an office this parameter becomes very significant, especially if the printer is used by several employees. Another important parameter related to print speed is the load cycle - the number of pages that the printer will print in a certain period of time (usually a month).

There is a rule: reducing the printer's printing speed leads to a decrease in its loading cycle.

There is another important factor in evaluating a printer - the type of paper used. This means not only special grades of paper for printing on inkjet or other types of printers, but also the size of the paper, as well as its density. Almost all printers work with standard sizes Letter papers in the USA and A papers in Europe; In addition to these sizes, several other paper sizes are supported. You also need to find out how the printer works with different paper sizes. Some printers have multiple paper trays built into them, some of which can be used for more than one type. When choosing an office printer, pay attention to the number of paper trays. When purchasing a printer, find out whether you can use thick paper and envelopes when printing. Printing on thick paper will work correctly if the printer has a special tray and the paper does not bend when printing. The ability to print on envelopes is sometimes implemented as an additional module.

The cost of consumables is the most important parameter when choosing a printer. Consumables include paper, color media (toner cartridge, ink cartridge or ink ribbon) and even the power consumed by the printer. Each type of printer requires a specific type of paper. Naturally, this paper is more expensive than regular paper. Laser printers can use several grades of paper, whereas an inkjet printer (especially color) requires a specific grade. The choice of paper is determined by the quality of the printed documents: for internal use You can use cheaper grades of paper, but for other types of printing you need to choose better paper. Having determined the color rendering medium, you need to calculate its “price per sheet” by dividing the cost of the cartridge by the number of sheets of paper on which you are going to print using this cartridge. Like the print speed, this parameter depends on the page coverage. Printing graphics uses more toner or ink. In laser printers, the price of toner depends on the model of the cartridge used. Some printers have a photosensitive drum and toner distribution unit installed in the toner cartridge, which increases its cost. There is no need to throw away your used laser or inkjet printer cartridge. Try to find companies that remanufacture used cartridges. A remanufactured and refilled cartridge (it also cleans the photosensitive drum) can be used several times, thereby saving significant money.

In addition to the cost of printing materials, when choosing a printer, you need to pay attention to power consumption and existing regimes work. The latest printer models support an advanced power management system and, during prolonged inactivity, switch to a low power consumption mode. Don't forget that in addition to saving your own money, you are saving the environment.

Before purchasing a printer, it is necessary to formulate all the requirements that it must satisfy. At home, you can get by with a regular inkjet printer with color printing capabilities. If you need high quality documents, pay attention to laser printers. Well, if you constantly move with a laptop computer, you need a portable printer.

2. Spreadsheet processors: document structure (cell, sheet, workbook, work area), cell attributes, cell content types and methods for setting them

Spreadsheets - uh Spreadsheets provide comprehensive tools for storing and processing various types of data. Table processors are the most popular Microsoft Excel(for Windows), Lotus 1-2-3 and Quattro Pro (for DOS and Windows).

The Excel spreadsheet also supports general functionality of word processors, such as the use of macros, charting, autocorrection and spell checking, the use of styles, templates, data auto-formatting, data exchange with other applications, and the availability of advanced help system, printing with parameter settings and other service capabilities.

It is advisable to use the Excel spreadsheet processor to create tables in cases where complex calculations, sorting, filtering, statistical analysis of arrays, and construction of charts based on them are expected.

Let us describe the main key concepts used when working with table processor Excel.

Workbook is basic Excel document. It is stored in a file with a random name and xls extension. When creating or opening workbook its contents are presented in a separate window. Each workbook contains 16 worksheets by default.

Sheets are designed for creating and storing tables, charts, and macros. The sheet consists of 256 columns and 16384 rows.

A cell is the smallest structural unit for storing data within a worksheet. Each cell can contain data in the form of text, numeric values, formulas, or formatting options. When you enter data, Excel automatically recognizes the type of data and determines the list of operations that can be performed on it. Based on their content, cells are divided into source (influencing) and dependent. The latter contain formulas that have links to other table cells. Consequently, the values ​​of dependent cells are determined by the contents of other (influencing) table cells. The cell selected by the pointer is called the active or current cell.

The cell address is used to determine the location of the cell in the table. There are two ways to write cell addresses:

1. By indicating the column letter and row number of the table, which can be preceded by a $ sign indicating absolute addressing. This is the default method and is called A1 style.

2. By indicating the row number and column number following the letters R and C, respectively. Row and column numbers can be square brackets, which indicate relative addressing.

A formula is a mathematical representation of calculations performed on table data. The formula begins with an equal sign or mathematical operator and is written in a table cell. The result of the formula is the calculated value. This value is automatically written to the cell in which the formula is located.

A function is a mathematical notation that specifies the execution of certain computational operations. A function consists of a name and one or more arguments, enclosed in parentheses.

The cell indicator is a frame that allows you to highlight active cell tables. The pointer is moved using the mouse or cursor keys.

A list is a specially designed table that can be worked with as a database. In such a table, each column represents a field, and each row represents a record in a database file.

Functions in Excel are used to perform standard calculations in workbooks. The values ​​that are used to evaluate functions are called arguments. The values ​​returned by functions as a response are called results. In addition to built-in functions, you can use custom functions in calculations that are created using Excel tools.

To use a function, you must enter it as part of a formula in a worksheet cell. The sequence in which the symbols used in the formula must appear is called function syntax. All functions use the same basic syntax rules. If you violate the syntax rules, Excel will display a message indicating that there is an error in the formula.

If a function appears at the very beginning of a formula, it must be preceded by an equal sign, as in any other formula.

Function arguments are written in parentheses immediately after the function name and separated from each other by the semicolon symbol " ; ". Parentheses allow Excel to determine where the argument list begins and ends. Arguments must be placed inside the parentheses. Remember that when writing a function, there must be opening and closing brackets, and you should not insert spaces between the function name and the brackets.

You can use numbers, text, boolean values, arrays, error values ​​or references. Arguments can be either constants or formulas. In turn, these formulas may contain other functions. Functions that are an argument to another function are called nested. IN Excel formulas You can use up to seven levels of nesting of functions.

The specified input parameters must have valid values ​​for the given argument. Some functions may have optional arguments that may not be present when the function's value is calculated.

For ease of use, functions in Excel are divided into categories: database and list management functions, date and time functions, DDE/External functions, engineering functions, financial, informational, logical, browsing and linking functions. In addition, the following categories of functions are present: statistical, text and mathematical.

With the help text functions It is possible to process text: extract characters, find the ones you need, write characters to a strictly defined place in the text, and much more.

By using date and time functions you can solve almost any problem related to date or time (for example, determining age, calculating work experience, determining the number of working days in any period of time).

Logic functions help create complex formulas that, depending on the fulfillment of certain conditions, will perform various types of data processing.

Excel is widely represented mathematical functions. For example, you can perform various operations with matrices: multiply, find the inverse, transpose.

By using statistical functions it is possible to carry out statistical modeling. In addition, it is possible to use elements of factor and regression analysis.

Excel can solve optimization problems and use Fourier analysis. In particular, Excel implements an algorithm fast conversion Fourier, with which you can build the amplitude and phase spectrum.

Excel contains over 400 built-in functions. Therefore, it is not always convenient to directly enter the names of functions and the values ​​of input parameters into the formula from the keyboard. Excel has special remedy to work with functions - Function Wizard
. When using this tool, you are first asked to select the desired function from the list of categories, and then a dialog box prompts you to enter input values.

With a huge variety of printers on the market, it is sometimes difficult to make a choice. Before going to an office equipment store, it is better to first get acquainted with the types of printers that currently exist and their characteristics. You can use the services of a store manager, but it is better to prepare and become a specialist yourself, since his opinion is not always objective.

Black and white inkjet printers are no longer available. Color ones are convenient in cases where you need to print photographic quality documents at low speed. Their ink consumption is high and the cost of printing is high. Cartridges can be refilled with ink, but printer manufacturers do not sell original ink. You can buy compatible ones from third-party manufacturers.

The market offers a wide range of printing devices. Knowing what types of printers exist and how they differ, you can make right choice. Each type of device has its own advantages and disadvantages. Having familiarized yourself in detail with the types of printers, you can choose the type that is most suitable for you. home use or to solve problems in the office.

Equipment manufacturers produce various models peripheral devices for printing, which may vary technical characteristics, appearance, size, features of work. Depending on the technology used, the basis of the work is the following main types of printers:

• matrix;
• jet;
• laser;
• LED

The types of printers also include MFPs - multifunctional device, which does several things. Each type has its own characteristics and characteristics, and also copes with different tasks. Before you go to the store to buy a new device, read more about the types of printers and their characteristics.

These are the first printing devices, the peak of their popularity was more than 10 years ago. Now their place has been taken by more modern models, so the production of matrix devices has practically ceased.

Operating principle

The operating principle of dot matrix printers is in many ways similar to a typewriter. The device is based on a matrix that consists of needles (usually 9, 18 or 24). Now only devices with a 24-needle matrix are produced, which allows you to obtain the highest print quality. Between the paper that moves on the shaft and the printing unit (matrix) there is an ink ribbon. When the needles hit it, the points from them are transferred to the paper. Printing codes for characters, letters and numbers are stored in the device’s memory.

Pros and cons

Such printers have the following advantages:

• low price of the device;
• simultaneous printing of up to 3 copies (tracing tracing paper must be placed between the paper);
• printing on roll paper;
• low cost of printing one sheet.

Dot matrix printers cannot provide high quality printing, and they are also quite noisy. Printers of this type are an excellent option for enterprises where there are no conditions for more modern models or where copies of documents are made in large volumes, but there are no high quality requirements. They are not suitable for home use due to low quality printing and noise.

Over the past decade, inkjet printers have made great progress in development. They allow you to obtain high quality color printing. Black and white models of such devices are no longer available.

Operating principle

Inkjet printers print by spraying ink through very small nozzles. The image is made up of small dots. For printing, quick-drying inks of four colors are used:

• Black (black);
• Cyan (blue);
• Magenta (magenta);
• Yellow (yellow).

Modern inkjet photo printers use 6 colors, which allows for increased brightness and color saturation. Features of printing technology different manufacturers may have slight differences.

Pros and cons

This type of printer is popular among users because it has the following advantages:

• affordable cost of the device;
• high quality color printing;
• the ability to print photographs using special photo paper;
• almost silent operation;
• economical in terms of energy consumption;
• Possibility of printing on paper, film and other materials.

Another advantage is the versatility of some models; for example, you can print photos from a camera without connecting to a computer.

The disadvantages include:

• high cost of printing;
• slow printing speed (compared to laser models);
• high cost of maintenance (purchase of ink cartridges and special paper).

Inkjet devices are suitable for those who want to print high-quality photos and color documents. The low cost of models of this type captivates many users, but keep in mind that the cost of consumables will be high. If the device is rarely used for printing, the ink may dry out and cartridges will need to be replaced.

Nowadays, printers that use laser technology are the most common, as they provide high quality printing and are distinguished by productivity. In most cases, printers of this type provide monochrome printing, but there are also color models.

Operating principle

The operation of a laser printer is based on a movable drum, like in a copier. Printing consists of several stages. First, a laser beam applies an image to a sheet of paper that moves on a drum. Afterwards, toner - a powder of electrically charged particles - is placed on the applied image and fixed by sintering while passing through a heated roller. Technology provides high-quality printing, which is not afraid of water and the rays of the sun.

Pros and cons

Many users choose laser printers for their advantages:

• high performance;
• low cost of printing;
• high printing speed;
• high-quality printing, resistant to water and ultraviolet radiation;
• low noise level.

The level of radiation is minimal, so the device does not cause harm to human health. Can be used for printing documents in large volumes.

The main disadvantage of such devices is the high price compared to models based on inkjet technology.

LED Printers

The new generation of printers using LED technology is still very expensive, so not everyone can afford such a model.

Operating principle

LED printing technology is in many ways similar to laser. The light source in such devices is not a laser beam, but a strip of LEDs. Application of this modern technology allows you to get high quality printing.

Pros and cons

LED devices, like other types of printers, have their advantages and disadvantages. The main advantages are:

• high quality printing;
• high speed;
• silent operation;
• performance.

Due to the high cost, this technique is still inferior in popularity to other types of printers.

A multifunctional device (MFP) is used for printing documents and photos, scanning and copying, receiving or sending faxes, as it combines the options of several peripheral devices at once.

Great for small offices with limited space, as well as home use. The combination of several peripheral devices in one allows you to save useful space.

Operating principle

MFPs can be based on inkjet or laser technology, and models powered by LEDs are also appearing on the market. The operating features of the device depend on the technology used.

Pros and cons

If you are interested in what types of printers there are today, you have become familiar with the main varieties. According to many consumers, MFPs are an excellent option for home use and small offices. It has the following advantages:

• combines several peripheral devices;
• costs significantly less than purchasing each device separately;
• allows you to save space;
• has low printing costs;
• can print on both sides;
• has high performance.

Depending on the model, some MFPs can be used for printing documents and photographs, but at the same time, such devices also have their disadvantages:

• if the MFP fails, the work of the entire office will stop;
• when the toner runs out, the scanner may not work;
• lower copy speed and higher copy cost.

Knowing all the main types of printers will help you make a smart choice. It is impossible to answer unambiguously the question of how to choose the type of device, since it is necessary to take into account the assigned tasks (how often and how much you plan to print), the required quality, operating conditions, financial capabilities and other factors. Do not forget to consider the features, disadvantages and advantages of each type.