Descibe a dot matrix printer
A dot matrix printer is an impact printer that transfers characters by striking a pattern (from a matrix) through an inked ribbon and onto paper.
- The most common number of pins on a dot matrix printer is 9, 18, or 24, with more pins providing a higher resolution. 24-pins create a near-letter quality print and anything with less than 24-pins provides a draft quality print. The overall print quality of a dot matrix printer is quite poor when compared to that of other types of printers.
- The speed of dot matrix printers is measured in characters per second (CPS). Common speeds for a dot matrix printer are 32 to 72 CPS.
- Dot matrix printers operate in either a font (letters, numbers and symbols) or dot-addressable (graphs and charts) mode.
- Dot matrix printers can use either a friction feed or a tractor feed system to move paper through the printing assembly.
- Because dot matrix printers strike the image onto paper, it is a good printer to use when carbon-copy documents are being printed.
- The print head can become dangerously hot due to pin friction.
- Dot matrix printers can be loud because printing takes place by pins physically striking the ink ribbon, paper, and the platen (a metal plate behind the paper).
Describe a Inkjet printer
Inkjet printers are quiet, non-impact printers with ink stored in a reservoir. Bubble jet printers are the most popular form of inkjet printers.
- The ink reservoir is in a disposable cartridge that includes the printing mechanism.
- Bubble jet printers print by heating the ink and squirting it through tiny nozzles in the print head and onto the paper.
- The crispness of an inkjet printer’s image is usually rated as dots per inch or dpi. Inkjets range from 150 to over 1400 dpi.
- A new generation of inkjet printers produce photo-quality printouts when used with photo-quality paper.
- Photo-quality inkjet printers mix up to 16 drops of ink to form a single dot of color on the page.
- Inkjet printers feed single cut sheets of paper from a feed tray by clamping them between rollers and advancing them one print line at a time, from top to bottom, through the printer. The newly printed paper is then placed into a tray other than the feed tray.
- Inkjet printers are an inexpensive way to produce color printouts.
Describe a Dye Sublimation (Dye Diffusion Thermal Photo) printer
A dye sublimation printer is a non-impact printer that uses film-embedded dye.
- The print head heats and passes over the film, causing the dye to vaporize and soak into the film paper.
- Dye sublimation printing prints in transitioning colors rather than pixels.
- Produces photographic quality images.
Describe a Solid Ink printer
Solid ink printers melt ink onto the print head (which is as wide as the paper). The head jets the melted ink onto the paper as the paper passes by on the print drum (similar to the laser printing process).
- Solid ink printers offer the following advantages:
- Simple design
- Excellent print quality
- Easy set up and maintenance
- The head takes as long as 15 minutes to heat prior to printing
Describe a Thermal printer
A thermal printer is a non-impact printer that uses heat to cause a reaction on specially treated paper.
- Monochrome thermal paper is chemically treated to darken where heated (photosensitive). Many cash registers use this type of printer for creating receipts.
- Color thermal paper is chemically treated to absorb color from a ribbon where heated.
- Ink is applied using the ribbon in a similar manner to a solid ink printer.
- The color system used by thermal printers is CMYK (cyan, magenta, yellow, and black).
- The paper must make one pass for each application of a different color.
- The feed assembly takes the thermal paper off the roll and it sends it through the printer to the outside of the printer.
- Color thermal printers are very expensive, high quality, and operate quietly.
Describe a 3D Printer
A 3D Printer creates a physical object by taking a digital model and manufacturing the object layer by layer.
- There are many different 3D printing technologies and materials that can be used depending on the object to be created.
- The materials that 3D printers use to create objects are called filaments.
- The most popular filaments are ABS (Acrylonitrile Butadiene Styrene) and PLA (Polylactic Acid).
- 3D printing can be done using many different kinds of filaments such as PVA, PET, PETT, HIPS, nylon, wood, sand stone, metal, magnetic iron, conductive PLA, carbon fiber PLA, flexible/TPE 3D printer filament, glow in the dark, and amphora 3D printer filament.
What components dor laser printers share?
In addition to the laser, laser printers share the following components:
- Laser printers use a laser and electrical charges to transfer images to paper.
- Laser printers move paper through the printer via motorized rollers.
- Each laser printer has a high-voltage power supply to charge the drum. This power supply converts AC current into higher voltages required for the printing process.
- Each laser printer has a DC power supply to operate most of the electronic components inside the printer.
- Each laser printer has a controller, which is a circuit board that acts like a motherboard in the printer. This controller board makes it possible for the printer to have and add its own memory.
- Laser printers are classified as page printers, because they print text and graphics simultaneously one complete page at a time.
- Laser printers use a laser to charge a metal drum. The drum picks up plastic toner, and the toner is then fused onto the paper (using rollers and heat).
- Of all the types of printers discussed in this course, laser printers have the highest print quality.
- A duplexing assembly is required to print two-sided output on a laser printer. Many inkjet printers also use duplexing assemblies to print two-sided paper. Duplexing assemblies are typically mounted on the back of a laser or inkjet paper.
- A transfer belt is used on some high-end color laser printers. Colors are applied to the transfer belt and then to the paper. This step is repeated for different colors
Describe the steps in the laser printing process
Step
Description
Cleaning
The cleaning phase prepares the drum by removing the previous image printed. It uses a rubber cleaning blade to remove any excess toner on the drum and then it scrapes off the debris into a debris cavity. Next, a heat roller is lubricated to ensure that enough heat will be evenly applied to transfer the next image printed. Then an electrostatic erase lamp neutralizes the electrical charges that remain on the drum from the previous printed image.
Processing
The printer receives a document to be printed from the connected computer and converts it into a bitmap raster image, which is divided into horizontal raster lines.
Charging
The primary corona prepares the photosensitive drum for writing by causing it to receive a negative electrostatic charge. Depending on the printer, the primary corona will be wires or rollers.
Exposing
A laser beam changes the charge on the surface of the drum in a pattern of the page’s image.
Developing
The developing roller applies toner to the drum. The toner sticks to the charged areas on the drum.
Transferring
The transfer roller charges the paper to attract the toner.
Fusing
The fusing assembly attaches the toner to the paper using rollers that press and melt the toner to the paper. As the paper leaves the printer, a static eliminator strip removes the static charge from the paper.
Printers use what methods for connecting to a computer or a network and receiving print jobs?
Connection Type
Description
USB
Most printers use a USB connection, allowing for configurations that also include scanners, external drives, or additional printers. The USB connection increases speed considerably over a standard serial or parallel port.
Wireless
Many printers allow you to connect using a wireless connection. This is especially useful when working with laptop computers.
- Bluetooth is a wireless technology for creating simple connections between two devices. Unlike infrared, line-of-sight connections are not required.
- 802.11a/b/g wireless standards use radio waves and are used to create wireless networks between multiple devices.
Network
Some printers also have their own network interface card, which allows them to connect directly to a network. Network printers can also be connected to a computer that is connected to the network. Another way to connect a non-network-ready printer to a network is with a network interface device. Network printers are useful for allowing multiple people to share the same printer. This is a common way to connect printers used in a business environment.
When purchasing a printer, what factors should you consider?
Consideration
Description
Connection Interface
Make sure that the printer you choose has an interface supported by your computer. The two most common interfaces in modern printers are USB and network interfaces.
Print Quality
Print quality is often measured in dots per inch (DPI). The higher the DPI, the higher quality the image.
Print Speed
Print speed is expressed as the number of pages that can be printed in a minute (PPM or pages per minute). Printers often rate both the black and white and color print speeds.
Memory
Printers can improve performance by having significant built-in memory. Additional memory improves performance and reduces the processing load on computers. In some cases, you can add or upgrade the memory in a printer.
Additional Features
Printers can include additional features such as:
- Additional paper sizes
- Double-sided (duplex) printing
- Document or sheet feeders
- Built-in scanners, copiers, or faxing capabilities
- Automatic collation or stapling
- Color printing
- Built-in network support
- Built-in hard drives or memory for storing and recalling printed documents
Print Driver
The software that allows the printer to communicate with the print device. Printer drivers provide the following support functions:
- Translate data into a recognizable form for the given printer
- Manage graphics via graphics drivers, converting graphics into the appropriate printer commands
- Allow management of the print job by displaying print and printer properties in the operating system
Printer
A virtual device (logical software entity) inside the print server that can be configured to send output to a print device. The printer is made up of the print driver, the printing device, and the spooler.
Print Device
The physical device connected to the print server where print output occurs.
Print Queue
The portion of the hard drive where print jobs are stored before going to the print device.
Printer Port
The means by which a print device connects to a print server (the printer’s NIC). Many printers can be configured in the same way that most plug-and-play devices are.
How do you configure a printer?
To configure a printer, you:
- Connect the print device to an available port.
- Create a printer object. For plug-and-play printers connected to a USB port, the printer might be configured automatically.
- Edit the printer object to configure device-specific settings such as color profiles and paper trays, or features such as stapling or double-sided printing.
- Verify that the printer works by sending a test print.
- Ensure that the customer or user knows how to use the printer and any additional features.
- If you have more than one printer configured on your computer, the default printer is the printer that will be automatically selected.
When an application sends a print job, what process takes place?
When an application sends a print job, the following process takes place:
- An output file is created that contains commands that the printer understands. The output file is sent to a virtual printer where the print job may be configured.
- A Device Driver Interface (DDI), which allows the document to interface with a printer driver, is created.
- A local spooler sends the file (print job) to the print driver.
- The spooler tracks the printer ports and printer configuration, and assigns print queue priority to the print job.
- The print job is concurrently stored on a disk file.
- The printer driver creates the correct print document format.
- The print job is then sent to the printer and is physically printed.
What three laguages do printers commonly understand?
Language
Description
Escape Codes
Used to control dot matrix printers. Escape codes are primitive compared to today’s standards.
Printer Command Language (PCL)
Hewlett-Packard has created several versions of a printer command language called PCL. Many modern printers understand PCL.
PostScript
Adobe created a printer language called PostScript that easily handles scaling of certain fonts and images. Printers that understand PostScript are usually more expensive than other printers.
Adobe created PDF as a successor to PostScript. PDF allows you to distribute documents on the web and have them displayed consistently in a wide variety of environments. Adobe has also provided Acrobat Reader free for multiple platforms and promoted PDF extensively, so it has become the de facto standard for page description languages.
Describe the 4 virtual printing options
Virtual Printing Option
Description
Print to File
If you use Print to File, Windows saves the formatting and layout information of your file so a printer can create the document without the program or computer that created it. This allows you to:
- Archive a document and print it later
- Send a document or photo to a commercial printer
- Send a document to someone who has the same printer, but doesn’t have the program you used to create the document
Print to file has some limitations. It’s generally designed for parallel printers and it doesn’t work well with newer USB printers. In addition, both the computer used to print the saved file and the computer used to create the file must have the same printer driver.
Print to PDF
Microsoft Print to PDF allows you to print your document to PDF format.
Print to XPS
Print to XPS allows you to create .xps files using any program that you can print from in Windows. Use the Microsoft XPS Document Writer when you want to view, save, share, digitally sign, and protect your document’s content.
Print to Image
Print to Image allows you to print any document into an image file that is independent of the application you use to view them. For example, you can convert a Word document into a .jpg file. The resulting images are print-ready and optimized for websites, smart phones, and tablets. You can also print them on a physical printer for excellent printouts.
Network printing uses what three special processes and components?
Network printing uses the following three special processes and components:
- The client application generates the print job on the local system. This process is known as spooling.
- The print job is sent to a print queue. The queue is a location for storing waiting print jobs.
- A print server is responsible for managing the flow of documents from the queue to the printer. When the printer is ready, the print server takes the next document out of the queue and sends it to be printed.
Ways to Connect the Printer to the Network
The printer must have a connection to the network (either wired or wireless). This can be done in one the following ways:
- Install a network interface card in the printer.
- Connect the printer to a workstation or server that is connected to the network. The printer is shared to make it available to other computers.
- Connect the printer to a special print server that has a network connection.
- Use Bonjour networking technology service to allow you to share a printer on your local area network.
- Use AirPrint to enable wireless printing capability on Apple iOS devices.
- Use Google Cloud Print to wirelessly send jobs from internet-connected devices to a remote printer.
If the printer itself does not have a network connection, use the USB port to connect the printer to another device.
How do you configure a printer attached to a Windows computer as a network printer?
To configure a printer attached to a Windows computer as a network printer:
- Connect the print device to the computer.
- Configure the printer object where the print device is connected.
- To share the printer, do the following in Windows 10:
- Select Start.
- Select Settings.
- Select Devices.
- Select Devices and Printers.
- Right-click the printer you want to share and select Printer Properties.
- Select the Sharing tab.
- If necessary, configure additional drivers to support client computers.
- On a client computer, create a network printer object using the share name of the shared printer. To manually identify the shared printer, use the format: \computername*sharename*
How do you connect to a network-attached printer or one using an external print server?
To connect to a network-attached printer or one using an external print server, create a printer using a TCP/IP port. Use the IP address and port name information to connect to the printer. Also, with network printing, you should be aware of data privacy issues when using public devices. When you send a print job to a network printer, your job is cached to the hard drive and saved there
Preventive maintenance for laser printers
Element
Recommended Maintenance
Environment
Keeping printers in a clean, safe area helps prevent premature failure. An optimal printing environment includes:
- Keeping the printer in an area with minimal amounts of dust or other air debris will help the printer to run smoothly and will extend the life of its mechanical components.
- Using surge protectors will help protect a printer from the effects of power surges and spikes.
- Providing proper ventilation will help a printer to not overheat. Excessive heat causes electrical components to degrade rapidly. Avoid keeping printers in closets or rooms that aren’t properly ventilated.
Maintenance Kits
Following the manufacturer’s recommendations for the installation of maintenance kits can greatly extend a printer’s life. Most maintenance kits include replacements for the most commonly used components of a printer such as:
- Fuser wires
- Rollers
- Toner drum
If these parts are replaced on a regular basis (usually after about 20,000 pages of printing), you can avoid a great deal of common printer problems. It is important to buy the maintenance kit for your exact make and model of printer.
Toner
A printer’s reported toner level isn’t based on how much toner is left in the cartridge, but on how many pages have been printed since the toner cartridge was installed. For this reason, it is important to check the actual toner level periodically. If the cartridge still has sufficient toner, but you are receiving prompts that say that toner level is low, you can reset the toner page counter by following the instructions in your owner’s manual.
The toner cartridge might include some of the components necessary in the printing process such as the developing roller, corona wire, and OPC drum in a single cartridge referred to as an electrophotographic (EP) cartridge. If this is the case, these components are replaced every time you change the toner.
Excess toner can clog up the inner components of a printer over time. Toner has a magnetic charge, so it is important that it only be cleaned by an anti-static vacuum cleaner. The dust and toner on the inside of printers should be cleaned out on a regular basis.
