Thermal Printer Color.

Thermal Printer Color.

1 - The color thermal printer pulls a paper sheet with a special texture banjeja into the mechanism of
transport in which paper is stuck on one side by a bearing which presses against a broad coated paint film
mixed colored wax or plastic. The film contains a range of each color composition - cyan, magenta,
Yellow and, if appropriate, black. Each color band covers a wide area - the length and the length of a sheet of paper.

How Does Thermal Printer Color.

How Does Thermal Printer Color.
The greatest desire of all printer manufacturers would be a color printer is fast and affordable. Although the
color printers are becoming more agile, smaller and more affordable, the very nature of combining colors
on a single sheet of paper automatically makes this already complex process.
Whenever looking for a color page printed, you will be seeing a complicated arrangement of only four colors - cyan (blue), magenta (red), yellow and black. (Sometimes black is not included because the printer is capable of generating Black - not always fully satisfactory results - combining equal intensities of the other three colors.)

Inkjet Printer.

Inkjet Printer.

1 - A cartridge (cartridge) with ink on the print head (print head) printer inkjet moves the lateral extension of the paper, which in turn is powered by the tractor printer under the printhead.


2 - The print head comprises ink compartments 50, each connected to an orifice (nozzle) smaller than a thread hair.

How the Work Inkjet Printers.

How the Work Inkjet Printers.
The inkjet printers are a middle ground between the matrix of impact and laser printers. These small
printers that fit almost any table, have the same resolution accurate lasers. Only
through a close examination you will be able to tell the difference between a print made by a laser and another by a inkjet.
Like all laser mechanisms, models inkjet spare our ears the creaking of printers
impact. What you hear is a small whisper followed by a small jolt when the leaf springs out.
Despite its similarity to laser printers, the inkjet models resemble more the matrix.

Laser Printer.

Laser Printer.

1 - The PC operating system or a program sends signals to the laser printer to determine where each point of the toner printing will be put on paper. The signals can be of two types - a simple ASCII command or any
page description language. (See How They Work and Vectorial Bitmap Fonts.)



2 - The processor instructions printer quickly activate and deactivate a laser beam.

3 - A rotary mirror deflects the laser beam so that it draw a horizontal line on the surface of a cylinder known as cartridge organic photoconductor (OPC acronym of Organic Photoconducting Cartridge), usually called
Only cylinder.

How does the Laser Printer.

How does the Laser Printer.
Each time you send a page to your laser printer (commonly this type of equipment is called printer
laser, but not everyone uses a mechanism with laser beams), you are at the same time, triggering a series of
complex procedures as efficient as a factory and as accurate as a well-choreographed ballet.
At the heart of the printer is printing module - the mechanism that transfers a black powder for the page - one
device node whose ancestor the copier. Parts represent the highest standards in terms of technology
printing, including imaging laser, the drive needs to paper and a microprocessor which controls
all these tasks.
To create an impression of high quality graphics, which is characteristic of laser machines, the printer controls
mandatory five tasks simultaneously: (1) it must interpret the signals from the computer, (2) convert such
instruction signals for controlling the movement of the laser beam (3) to control the movement of the paper (4) to polarize the
paper so that it attracts black toner that will compose the picture and (5) fuse toner deposited on the paper.
The result is an excellent impression. The laser printer not only produces copies faster than dot matrix printer,
pages are also more accurately detailed than those produced in matrix. In brief, the laser printer is
become standard for high quality printing on computer systems.

Source: Evolution of Computers

Dot Matrix Printer.

Dot Matrix Printer.


1 - PC sends a series of ASCII codes representing characters, punctuation marks, and moves the printer, such such as tabs, carriage returns and form feeds, which control the position of the print head in relation to
paper.

2 - The ASCII codes are stored in the buffer, a special part of the printer's RAM. The time it uses the matrix
for printing characters is normally greater than the time it takes the PC program and to send these same
characters to the printer, so the buffer helps to release the PC to perform other functions while printing. Generally, the internal buffer of a dot matrix printer has the capacity to store only 7KB to 8KB. When the buffer is full, the printer sends XOFF control code to the computer to stop sending data is suspended. When the buffer frees up space, sending some characters to its processor, the printer sends the control code XON to the PC, releasing sending data.

How Does Dot Matrix Printer.

How Does Dot Matrix Printer.
While laser printers are faster and manage documents and more elegant, the impact matrix printer
remains the flagship of many computer systems. Much of laser printers cost more than a thousand dollars,
being a reliable matrix costs only a few hundred. Laser printers require replacement
toner cartridge, which costs almost the same price of a matrix without great resources, all matrix need time
then a new tape that it is cheap.
Dot matrix printers are needed for tasks that require printing on multipart forms, something that
laser printer can not run at all. And now the 24-pin dot matrix printers have gained greater
improved their speed and print quality.
Manufacturers continue to release new matrix printers fast and smart - and less noisy. There are great
chances of impact dot matrix printers remain in the market for a long time yet.
Although some matrix can interpret PostScript commands or some other page description language, the
Most impact printers are designed to work with bitmap types controlled by ASCII codes
sent from the PC to the printer. (See How They Work and Vectorial Bitmap Fonts for more information about
bitmap types and page description languages.)

Source: Evolution of Computers

Sources Vectorial.

Sources Vectorial.


1 - vector fonts, unlike the bitmap fonts are not limited to certain sizes or attributes of a
typeface. They consist of mathematical descriptions of each character and punctuation of the typeface. Are
called vector fonts because the description of a capital A 36 point Times Roman family is the same as that of
a capital of 24 points Times Roman family.



2 - Some printers come with a page description language, usually PostScript or Printer Command Language
Hewlett-Packard in firmware - software embedded in a microchip.

Sources Bitmap.

Sources Bitmap.

1 - The bitmap fonts are types of a certain size and with certain attributes or characteristics, such as bold or italic.
The bitmap is a record of a model of points required to create a certain character from a certain size, with
given attribute. The bitmaps Uppercase average of 36 points Times Roman family, the capital A bold 36
Family points Times Roman Uppercase and average 30 points Family Times.

How They Work and Vectorial Bitmap Fonts.

How They Work and Vectorial Bitmap Fonts.
All printers, whether matrix, inkjet, laser or thermal perform essentially the same task - create
a series of dots on the sheet of paper. The points can be scaled in various ways, or different compounds
ink transferred to the paper in various ways, but all the images in both text and graphics are composed of
points. The smaller the dots, the better the end result.
Regardless of the number of points raised in the paper, there must be a common schema to determine the positions that the points are placed; schemes are the most common vector and bitmap fonts. Bitmap fonts come in sizes and different thicknesses. The vector fonts can be any size and have several attributes associated with them.

Printers.

Printers.
As soon as the first personal computers appeared, someone came to think that all these computerized data could determine the order of the paperwork in the office. We are more than a decade the emergence of PCs and millions of trees continue to be felled for the production of paper copies of various things, from budgets to complex business color images for cards party and thanks. Not only the number of printed materials is increasing every day as printing became exquisite. The real purpose of this new category of programs - it is named after publishing electronic (desktop publishing) - is nothing more than the pursuit of printed pages getting better.
Whoever made the wrong prediction about the free office papers, forgot one important detail.
This person certainly was thinking about as wasted paper at the time of the typewriter. In reality, there
was much more than letters and numbers to be placed on black paper - often in poor but efficient typology
Courier.

Communication Network.

Communication Network.

1 - The application layer is the only part of the communication process that the user sees, and even then, he does not see the bigger part of the work performed by the application to prepare the message to be sent over the network. The layer converts the data of a message (which can be read by any person) in bits, and appends a header identifying the sending computer and receptor.

2 - The presentation layer ensures that the message is conveyed in a language that the receiving computer can understand (usually ASCII). This layer translates the language, if necessary, compresses and perhaps encrypts data.  It adds another header specifying the language as well as encryption schemes and compression.

How It Works network communication.

How It Works network communication.
The messaging network is not simply a process of transmission of bits representing alphanumeric characters.
The communications network may involve personal computers that run on DOS, Macintosh line models, computers minicomputers and large, all having their own forms of management code and data transmission.
Adding the fact that each application of each of these platforms has its own pattern of communication, you
see that the sending and receiving of data simpler becomes a mammoth task.
To make sure that the data from one node of a computer reach another node or server that you want - and come intact and uncorrupted - it is necessary that the system be understood by all network components.
A system of this type follows the OSI (Open Systems Interconnection, or Open Systems Interconnection) that is followed by most Networked PCs. The seven layers of the OSI model is not exactly a specific set of hardware and software, but one scheme that can be implemented in various forms since such an implementation follow the OSI standard.
This standard is based on layers: each network component exists in a certain layer of the system, and each component can communicate only with the layer directly below or directly above it. Each layer provides services to the upper layer and may request the services of the lower layer.

Source: Evolution of Computers

Networks in Star.

Networks in Star.

1 - In a star configuration, the nodes are connected to separate lines, all directed to the same point or station
central. The central station contains the switchers that connect each line to the other.

Ring Network.

Ring Network.

1 - In the ring network (token ring), all the nodes are connected to the same circuit, which takes the form of a ring. A token
- Consisting of a small message permission - continuously circulates the ring, being read by the token ring
each node as it passes through it.

2 - The node that is waiting to send a message when it gets the token pass, changes its binary code to
say that it is being used, and appends the message, the address of the destination node and the verification code error.

Network Bus (Bus)

Network Bus (Bus).

1 - In a bus network, all nodes connecting to it like branches of a common thread. Each node has a unique address. The network card installed on a node, which can be another PC, a file server or a print server, make sure that no other signal is being transmitted through the network. Then sends a message to other peripheral through a transceiver (transceiver). Each node has its own transceiver.

Work As Local Network Topologies.

Work As Local Network Topologies.
The primary function of a network (LAN or Local Area NetWork) is physically connecting multiple PCs to each other and also to a mainframe or minicomputer. This is accomplished through a wide variety of materials - cables braided, fiber optics, phone lines and even radio signals and infrared.

There are several ways of connecting PCs both physically and logically. Each network configuration - or topology - must still perform the same tasks. The most common situation in which a network faces is sending messages from a PC to another.

How the Networks Works

How the Networks Works.
Before the advent of the PC, there was the terminal - a monitor somewhat dumb - and a keyboard, they allowed users from one location to have access to the same central computer. Generally, this computer was a great and mysterious sealed box, located in another room, managed by technicians wore lab coats.

The mere users were forbidden to enter the room and, of course, were not allowed to go directly to the
computer. The people who sat in front of the terminals had to be content with the blessings or failures that
Your computer or technical managers poured over them.

Pen-based Character Recognition and Movements

Character Recognition and Movements.

1 - After reading the position of the pen, the computer sends a signal to activate the screen (or off, depending on the color of background) found in the pixels pen position, a process known as marking paint. As the stylus moves, the computer calculates continuously its position and activates the remaining pixels. The computer pixels that differ match the position of the pen (input plane) of pixels activated by the application (Exit Plan). Note that the screen does not have two distinct levels of physical pixels LCD.

Pen-Based Computers.

Pen-Based Computers.

A type of computer-based pen uses liquid crystal display which has a wire mesh embedded. The level of
voltage current flowing through the wires when modifying an electromagnetic field created by the pen passes over the wire.

How the Computer Works Based on Pen

How the Computer Works Based on Pen.
Even the mouse is far from achieving the elimination of the keyboard, for sure the main barrier to computer use in various situations. This barrier is being attacked now by PCs with stylus.
The aim of this type of computer is to simulate a pad of paper and a pen common. With the width and height of a block paper, but generally thicker, such a computer can be supported with one hand while the other
write, draw or pick something on the flat screen LCD.

Optical Character Recognition (OCR)

Optical Character Recognition (OCR).

1 - When a scanner reads a document image, it converts the dark elements - text and graphical parts - the page in a bitmap (bitmap), an array of square pixels that can be active (black) or inactive (white). As
pixels are larger than most of the details of the text, this process degrades the thinner ends of the characters,
as occurs in the fax machine. The degradation creates most of the problems for optical recognition systems
Character Recognition (OCR).

Scanner Manual

Scanner Manual.

1 - When you press the scan button of a common manual scanner, a light emitting diode (LED) illuminates the image that is under the scanner. An inverted mirror angle, positioned immediately above the scanner window, reflects the image the lens located at the back of the scanner.

2 - The lens focuses on a single line of the image through a device called a charge coupled device, or CCD
(Charge Coupled Device), designed to detect sudden changes in voltage. The CCD has a line of
light detectors. When light strikes these detectors, each of which registers the amount of light as a degree of tension that corresponds to white, black, or gray color.

3 - The tensions generated by the CCD are sent to a particular chip analog to be made a correction range,
process which improves the black image tone so that the human eye is more sensitive to light than

Flatbed, Scanner

Flatbed, Scanner.

1 - A light source illuminates the piece of paper placed face to the glass window located above the
scanner. The voids or white reflect more light than the parts that have letters or pictures, colored or not.
2 - A motor moves the scanning head located below the page. The move allows the scanning head to capture light that bounces off of the main areas about 1/90.000 square inch each.

3 - light from the page is reflected through a mirror system constantly adjusted so that the beam
light are aligned with the lenses.