Theory Notes Task: Output Devices
Make sure that you are familiar with all of the information detailed in this booklet. There are a number of tasks for you to carry out, be sure to read the information fully whilst completing the tasks. You could be asked about any of this in the test! Use the theory notes in from the teach-ict.com site to help you complete this booklet. http://www.teach-ict.com/gcse_new/computer%20systems/output_devices/miniweb/index.htm
TASK 1: OUTPUT DEVICES Output devices let you see data that has been processed or is stored on the hard disk or any other storage media. A monitor lets you see data on the screen, a printer produces a paper copy that you can hold and read. Complete the table below: Output device Monitor
Description A monitor is the most commonly used output device. It allows you to see the document that you are working on. As you make changes to the document, the monitor automatically updates so that you can see your work.
Where used? Computer, TV, everywhere‌
Pros You can visually see what’s going on
Cons It can damage your eye
Laser printer
It prints things! Print in same way as photocopiers, Powdered ink, called 'Toner', is fused onto paper by heat and pressure.
Workplaces
Quiet, high-quality, fast, low cost
More expensive, esp. colours, toner more expensive than ink cartridges, expensive to repair, fairly bulky, Can't use continuous or
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Ink-Jet printer
Digital projector
Plotter
These printers use cartridges that contain ink. They operate by heating the ink as it flows through the nozzle. The heating process causes a small droplet of ink to form. This is then released as a single dot that forms part of a letter or image. This is why the printouts often come out of an ink-jet printer still slightly wet. Used to project images from a computer onto something, usually used with a smart board
Colour printers are good for homes where not much is printing is needed
Cheap to buy, more smaller than laser printer, cartridges cost less than toners, fairly good printouts, fairly fast
Presentation, home cinema, classrooms for teaching
Useful for showing things without having to get a giant screen
Draws high quality images on very large pieces of paper. A plotter differs from a printer in that it draws images using a pen that can be lowered, raised and moved across the paper to form continuous lines. The electronically controlled pen is moved around the paper by computer-controlled motors. There are also pen-less ones.
Engineers, architects, mapmakers, drawing giant plans
Can make large prints
multi-part stationary to create carbon copies like you can with a dotmatrix printer Noisy, colour printing slower than laser printer, cost per page is more expensive than laser, cartridges needs to be replaced more often, ink can smudge when wet, colours can be saturated and change, cartridges can dry out Needs to align with the board, using a smart board might not be that accurate
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Flatbed plotters – These hold the paper still while the pens move. Drum plotters – These roll the paper over a cylinder. Pinch-roller plotters – These are a mixture of the two types. Speakers
Most computers have a small internal speaker, you can get a sound chip and connect to an external speaker
Anywhere, home, school, laptops, computers, music rooms…
Everyone can hear it, they can create an atmosphere to accompany a presentation, help blind people by converting text to sound
Can disturb others, highquality external speakers can be expensive
Headphones
Has a pair of small speakers worn over the head, connected to an electronic device by a cable
Lot of places, school, workplace, home, music studio…
Only the person can hear, portability, inexpensive
LED Lights
Can be connected to a computer and respond to electrical signals which tell them to switch on and off.
Homes
Can be used in computer control simulation to show it is working, can be warning for hear loss people, comes in range of colours,
Risk of hear loss due to loudness, not aware of surrounding, if not worn properly others can hear, can be uncomfortable fro too long, if the device is large it may be hard to move around the room. Might break, may be loose connection so light won’t switch on even if program is correct
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TASK 2: FILL IN THE BLANKS Copy the sentences below and complete the blanks using words from the list. You should use each word only once. LAPTOP
PIXELS
SIZES
SCREEN
INCH
OUTPUT
DOTS
EXPENSIVE
Monitors These are the most common output devices. Sometimes they are called a screen instead. All desktop computers have a separate monitor, but a laptop computer will have a monitor that is attached by hinges. Monitors come in different sizes but the larger they are, the more expensive they tend to be. The picture on a monitor is made up of thousands of tiny coloured dots called pixels. The quality of a monitor depends on the number of pixels per inch. Printers CARTRIDGES
INK-JET
CARBON
LASER
RIBBON
TONER
HARD
Printers are useful for creating a hard copy of your work. There are two main types of printer: • •
Laser printer Ink-jet printer
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Laser printers work much like a photocopier; powdered ink is fused onto paper by heat and pressure. They produce a very high quality output, are quiet and fast, although quite expensive to buy. They use toner rather than cartridges. Ink-jet printers are cheaper to buy, offering black and white or colour printing with reduced levels of quality and speed. The nozzles fire a jet of liquid ink through tiny holes, hence the name, ‘ink-jet’. The ink is stored in cartridges.
TASK 3: CHOOSE THE MOST SUITABLE OUTPUT DEVICE Which output device would you recommend for the following tasks: To produce a large number of letters in high quality
Laser printer
Producing very large sheets such as blueprints
Plotter
Producing a small number of coloured leaflets
Ink-jet printer
Looking at changes that you are making to the document you have open Display a presentation to an audience
Monitor
Listen to music with friends
Speaker
Digital projector
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