Output Devices Flashcards
What is an output device?
An device that takes data produced by the computer and turns it into a from that humans can understand
What is a different type of output device?
An actuator, which might respond to an input signal to a turn on a sprinkler, open or close windows in a greenhouse or perform any number of other actions
What are some common examples of an output device?
Screens, printers, multimedia projectors, speakers and actuators
What are the different types of screens?
LCD monitor and, Organic LED (OLED) screens
What does LCD stand for?
Liquid Crystal Display
How does an LCD work?
LCD monitors contain groups of red, green and blue diodes to from each pixel, the screen is typically back-lit musing light-emitting diodes (LEDS)
What is the advantages of LCD monitors over older technology?
They reach their maximum brightness almost immediately
the image is sharper with more realistic and vivid colours
they produce a brighter light which leads to better picture definition
since LEDS are very small, screens can be much thinner in construction
They last almost indefinitely which makes the screens much more reliable
They consume very little power and therefore produce very little heat as well as reducing running cost
What are OLED screens compared to LCD or LED screens?
OLED are brighter, thinner and lighter than traditional LCD or LED screens
What is The material used for OLED screens?
The screen is plastic rather than glass, so they are flexible
What are the advantages OLED screens have over LCDs?
When made of plastic rather than glass, they are theoretically flexible enough to print onto clothing
They are much thinner
They are brighter and need no backlighting, so they consume less power, which translate into longer battery life
LCDs can be slow to refresh, OLEDs respond up to 200 times faster
They produce truer colours through a much bigger viewing angle, unlike LCDs where the colours darken and disappear if you look from the side
What are some disadvantages of OLEDs compared to LCDs?
OLEDs do not last as long, tending to wear out around 4 times faster than LCDs
They are sensitive to water, which is a potential problem in a cellphone
What are the different types of printers?
Laser printers, inkjet printer, dot matrix printers (also known as impact printers) and, 3-D printers
What does a laser printer offer?
High-quality, high speed printing
What is the function of a laser printer similar to?
That of a photocopier, using powdered ink called toner
Where is a laser printer commonly used?
Due to it becoming increasingly affordable, it is frequently used as a home printer, in businesses and in professional printing services
How many toner cartridges does a laser printer have?
Four (Cyan, Magenta, Yellow and Black or CMYK)
Why are colour laser printers far more expensive to run than black and white versions?
When the paper goes through the printing process, it does it four more time than the black and white one, as once for each colour
In what area does a laser printer become limited?
For print jobs other than text because of the quality of the print produced, which at about 120 dpi makes photorealistic prints impossible and best left to inject printers
How do inkjet printers work?
is sprays minute dots of ink onto paper to create an image
What happens when Inkjet printer has high resolution (dots per inch) of the model?
With the number of colour cartridges used and the quality o the paper being used and the quality o the paper being used, they can produce excellent, photo-realistic images
What is the advantages of Inkjet printers compare to laser printers?
Inkjet printers are cheaper, and is preferably used to produce high quality photographic images
What is the disadvantages of Inkjet printers compare to laser printers?
Inkjet printers ae slower and the ink cartridges have to be replaced quite frequently
What are dot matrix printers also known as?
Impact printers
How does dot matrix printers work?
The print head has a matrix of pins which strike the surface of the paper through an inked ribbon to from letters
What is some advantages of dot matrix printers?
These printers are useful when multi-part stationery is required and they can operate in damp or dirty environments
What is some disadvantages of dot matrix printers?
They are noisy, slow and the print quality is poor
What are some examples of output devices?
Multimedia projectors and computer speakers
What is actuators?
Actuator are motors that are commonly used in conjunction with sensors to control a mechanism for example turning a wheel, starting or stopping a pump or controlling devices in a ‘smart home’
