Output Devices Flashcards
Peripheral
An external device that is connected to a computer
Soft copy
Data and information that is virtual
Hard copy
Data and information that is physical
Footprint
The space taken up by peripheral
Pixel (3 points)
Short for picture element; it is illuminated dot; many pixels together form an image
Resolution
The number of pixels in a display
Display
An electronic device that outputs information via a screen or projection
List primary colours
Red,Green,Blue
Colour depth
The degree to which a particular colour can be represented
List 3+ and 2- of flat panel displays
+ High resolution
+ Made be at a size ideal for a portable device
+ Low energy requirements
- Easily damaged
- Dead pixels that will spoil the display
Two types of flat panel displays
LCD - Liquid crystal displays
LED - Light emitting diode
How does an LCD work?
Separate RGB pixels arranged in tiny blocks. The crystals can be made solid or transparent by altering the current
When the crystals are liquid….
Light can go through and the pixel is illuminated
What is more advanced LED/LCD
LED
How does an LED work?
Like LCDs but pixels are backlit with light emitting diodes. LED brighter and direct light
What has an uneven brightness across the screen
LED
What is thinner and lighter
LED
Unless viewing straight may be hard to see
LCD
How does a LCD processor work?
3 separate glass panels for each RGB colour, as the light passes individual pixels can be opened to allow the light trough.
When are LCD projectors useful?
When contrast and brightness are important
How does a DLP projector work?
Uses millions of tiny mirrors to reflect light towards the projection lens
Compare the image of a DLP projector to a LCD projector
DLP - excellent colour representaation, less contrast and brightness to LCD.
Which projector is smaller?
DLP
What base colours do printers use?
1) Cyan
2) Magenta
3) Yellow
4) Black
Types of printers (3)
1) Inkjet printer
2) Laser printer
3) 3D printer
How does an inkjet printer work?
Ink is sprayed on the paper through the microscopic nozzles
Advantages of inkjet printers (2)
1) Cheaper than other printers
2) Excellent image quality when using photography paper
Disadvantages of inkjet printers (4)
1) Use a lot of ink which is expensive
2) Poor image quality on normal paper
3) Difficult to print on both sides
4) Slow in printing
How does a laser printer work?
Use laser to create static electricity where the tonner sticks. Uses fusing element to bond tonner to the page
How do you call laser printer powder?
Tonner
Advantages of laser printers (4)
1) Cheap to run as they cartridges last longer
2) Text printing is good quality
3) Quick at printing
4) Duplex printing reduced paper cost
Disadvantages of laser printers (3)
1) Expensive to buy (laser technology)
2) Images on photographic paper is worse than on inkjet
3) Bigger than inkjet
What does CAD stand for?
Computer aided design
CAD
Software that allows a user to design and create an image of an object
What does CAM stand for?
Computer aided manufacturing
CAM
A computer controls machinery to manufacture an object
What does CNC stand for?
Computer numerical control
CNC
The method of control used by CAM
How does a 3D printer work?
Digital object is split into tiny horizontal layers. Printer uses material to slowly print each layer on top of the other
What materials can a 3D printer use? (3)
1) Polymers
2) Plastic
3) Acrylic
Advantages of CAM (3)
1) Items manufactured to a higher precision than by hand
2) High production quality can be kept
3) High quality bespoke items and prototypes
Disadvantages of CAM (3)
1) Training is required to use CAM
2) Bespoke items and prototypes may be expensive to produce
3) CAM is expensive to introduce because of hardware and software costs involved
What does DAC stand for?
Digital to analogue convertor
DAC
A device that converts digital signals to analogue
Advantages of a speaker (3)
1) Variety information to be provided to the user
2) Aid disabled user when operating a device
3) Warn large number of people (emergency)
Disadvantages of a speaker (2)
1) Built-in speakers - low quality
2) Sound may disturb the others
