- Mouse- This works using either a laser which the ray gets broken(shortened) as it is moved across a surface. Or, a ball mouse which as it is rolled across a surface it hits a switch at either side of the mouse.
- Voice reconition- This works by recording the input and relating it to a command (compares it)
- Graphics tablet-This works as it has small sensors throughout it which when pressed on pickup how hard the pen is pushed onto, thus making so that different pressures can be pcked up.
- Keyboard-A key board worksas it has metal contacts under the plastic keys that when pressed together complete a circuit letting the computer know what button has been pressed.
- Touch-sensitive screen- This works by putting a feild of lasers across the screen. When these are broken by a finger/object it lets the hardware know where it is being pressed.
- Digital Still/video camera
Magnetic
- Magnetic stripe reader-The card has magnetic parts which when swiped are picked up as 0's and 1's
- Smart card reader-has a chip that is read by the smart card reader. this small chipcan store small amounts of information and even small software.
- Bar code reader-the bar code reader reflects lasers off the strip(white reflects the laser back better) and thee are picked up as 1's and 0's
- Optical mark reader-LIke the bar code reader this uses lasers that reflect lighter parts back and black parts not as much, where these are on the page corespond to where the light from the laser doesn't return.
- Optical character recognition- This captures the characters on the object and compares them in its database of character(this is to reconise them) and then they are pasted.
- Radio frequency identification reader-This uses exlectro magnetic waves(radio signals) and sends them out from where ever it is so that it can be located (this would normaly be placed on an object like a bag at an airport so that it could be easily located/allocated.
- Fingerprint scanner-This uses a light that reflects nicks and bumps in the skin back to the machine giving it an image that can be used to identify someone.
- Retina/Iris scanner-This uses a very weak laser which is shone into the eye of the person and picks out unique characteristics from the retina/iris. this can then be used to identify people.
- Flatbed scanner- A light is shone onto the object in the scanner which is reflected back as an image and picked up by a sensor. CCD-type scanners typically contain three rows (arrays) of sensors with red, green, and blue filters.
Displays
- Cathode ray tube (CRT)- This works with a vacuum tube containing electrons and a fluorescent screen. These are used to create the image on the screen (The light emitted from the fluorescent screen)
- Plasma screen- This works as he xenon and neon gas in a plasma television. This heats up the magnesium oxide which in turn goes through colour panels, the back of each cell is coated with a phosphor. The ultraviolet photons emitted by the plasma excite these phosphors to give off coloured light(this is what we see)
- Flat screen (Liquid crystal display LCD)-This works by using the light modulating properties of liquid crystals. These are lit up with blue green and red LED's.
- Inkjet printer- These spray ink onto the paper (droplets)
- Laser printer-These work by using using dry ink (toner), static electricity, and heat to place and bond the ink onto the paper. The paper is rolled over a drum as this happens
- Impact(dotmatrix) printer-a series of small pins to strike a ribbon coated with ink, causing the ink to transfer to the paper at the point of impact.
- Plotter-A plotter is a graphics printer that uses a pen or pencil to draw images. Plotters differ from printers in that plotters use continuous lines to create images while printers use a collection of dots.
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