Output Devices Output Devices p Output devices

Output Devices

Output Devices p Output devices allow us to receive information from the computer system n Monitor (LCD and TFT) n Speakers n Plotter n Printers (Inkjet and Laser)

Monitor p Used to display data using a screen p There are two types of monitor, LCD and TFT

Liquid Crystal Display (LCD) Flat screen p Consists of a thin layer of fluid between two sheets of plastic p Can be colour or black and white p Used in: p n n Calculators palmtop computers Laptops ultra-thin computer monitors

Thin Film Transistor (TFT) Flat screen p Consists of one transistor for every pixel p Has better quality (sharper pictures and better colours) than LCD p Used in: p n n Laptops Flat screen monitors

Printers are devices that produce a hard copy of the output from a computer. Output can be: n Black & White (Monochrome) or Colour There are two types of printer: Laser n Inkjet n

Laser Printer p. A type of printer that uses toner and a laser beam to print images onto paper Toner is a powdery substance. The laser “draws” the image inside the printer. A high temperature inside the printer makes the toner “stick” to the paper in the right places as the paper passes through the printer.

Inkjet Printer p. A type of printer that sprays tiny streams of coloured ink (like paint) onto paper through tiny holes in the print head. A print head is a small part of the printer that moves backwards and forwards as the paper passes through the printer.

Inkjet vs Laser p You need to be able to compare inkjet and laser printers in terms of their speed, resolution, initial cost and running cost n Speed (Measured in pages per minute - ppm) p n Resolution (Measured in dots per inch – dpi) p n Inkjet – high, Laser – very high Initial Cost (The cost to buy the printer) p n Inkjet – slow, Laser – fast Inkjet – cheap, Laser – expensive Running Cost (The cost to buy ink/toner) p Inkjet – expensive, Laser - cheap

Plotter Used for accurate drawings/designs on paper p Paper can roll backwards and forwards p Uses special pens to print on rolls of paper p Used by architects p

Speakers/Headphones p Used to output sound p Headphones are “personal” speakers

Specialised Output Devices for Virtual Reality p User wears a headset which contains a screen and headphones.