CIS 1 - Kurtz  Santa Monica College 

INPUT & OUTPUT

 

 

Ink‑jet Printers 

 

Spray magnetized ink onto paper

Ink cartridges are replaced when they run dry

Cartridges for black, yellow, magenta, and cyan

Color cartridges are often combined into one.

Cost is low enough for home use

 

Dot Matrix Printers 

 

Tiny solenoids "impact" an inked ribbon against paper

Used for multi-part forms

The ribbon is replaced when it gets dry.

Inexpensive, rugged, and noisy

Low print quality

 

Laser Printers 

 

Laser writes to a light sensitive drum which transfers toner to paper

A toner cartridge is replaced when toner is expended.

Toner cartridge also contains the print drum.

Robust enough for shared office use

 

Thermal Printers 

 

Paper reacts to heat and electrical charge and changes color

Special coated paper is required

Very inexpensive

Low print quality

 

Cathode Ray Tube 

 

CRT

 Type of video monitor 
Similar to a television screen 
Beam of electrons is emitted by an electron gun (cathode) which illuminates phosphors on the screen, causing them to glow 
Monochrome monitors use one electron gun 
Color monitors require three electron guns, red, green, and blue (RGB) 
Monitor screens are made up of individual pixels or picture elements 
Typical PC Monitor resolutions: 

640 x 480 (640 pixels across and 480 pixels down) 
800 x 600 
1024 x 768

More pixels make images smaller and smoother

Liquid Crystal Device

LCD

Uses Liquid Crystal Material sandwiched between polymer layers

LCD elements are activated by an electrical current.

Active matrix, or TFT technology is brighter, has better color, is visible at an angle, but more power is required

Passive matrix requires less power but is visible only from front

Low Power

Flat screens take up less space than older CRT monitors

Television

 

May be used as output devices

Digital televisions (e.g., HDTV) are superior to analog televisions

Analog televisions may require a converter

High Definition Television (HDTV) is an advanced form of digital TV with more raster lines resulting in superior image quality

 

 

Alphanumeric Keys 

 

Letters, numbers, and punctuation marks
"QWERTY" arrangement similar to typewriter

 

Function Keys 

 

Labeled F1, F2, etc. 
Get their meaning from the program being executed

Have no intrinsic pre-defined functions

 

Cursor Keys 

 

Used to move cursor on screen 
Arrow keys, PgUp, PgDn, Home, End

 

Numeric Keypad 

 

Similar to a 10‑key calculator keypad

 

Special Keys 

 

NumLock, Control, Shift, Alt, Esc, Insert, Del, Enter, Backspace

Scanners

Capture an image of a document directly

Resolution in dots per inch (dps)

Optical Character Recognition

OCR

Used to convert scanned document images into a native format such as Word, Excel, etc.

Optical Mark Recognition

OMR

Scans for marks on a form such as a Scan-tron

Magnetic Ink Character Recognition

MICR

Recognizes Magnetic Ink in shape of special characters

Used primarily in banking industry

Bar Codes

Optically scanned

Used in retail (grocery, pharmacy, hardware, stationary, etc.),

Vehicles, mail, books, etc.

Plotters and Large Format Printers

Used in engineering, drafting, and graphic arts

Large Format Printer

Electrostatic Plotter

Pen Plotter

Used for large printed output

Audio Output

Speakers & Headsets