pc output devices

        Monitor

        Sound box

        Printer

        Pendrive

                             (ETC)

Output Devices

•        Any computer component capable of conveying information to a user; which is called output.

•        The devices that serves that purpose is called output device.

> Display Devices

> Printer

> Sound devices or Speakers

> Others

Audio output

•        Audio output devices

> Produce music, speech, or other sounds

> Speakers

> Headsets

How a Sound Card Works and Speaker Create Sound? 

CRT Monitor

•        Contains a cathode ray tube, a large sealed glass screen.

•        The screen is coated with tiny dots of phosphor materials

•        Pixel is the single point of a viewing image

•        Three dots: Red, Green & Blue combine to made up pixels

LCD Monitors

•        Liquid crystal display

•        Contains liquid crystals between two sheets of materials to display images on screen

•        An electronic current passes through the crystals which creates the image on the screen

Factors that influence the quality of a color monitor

•        Screen size – measurement in inches from one corner of the screen diagonally across to the opposite corner.

•        Pixels are small dots. 

•        Dot pitch (the space from one pixel to another) is a measure of image clarity: – the more pixels per inch, the smoother the image

•        Resolution number of columns and rows of pixels displayed on the screen

     -it  is the number of pixels that are displayed at one time. (800 x 600)

Digital Light Projector

•        Connects to a computer and is used to project images on a large screen

> LCD projectors – room must be darkened

> Digital Light Processing uses digital micro mirror devices for brighter, crisper output.  Can be used in normal lighting conditions.

Impact Printer

•        Creates an image by using pins or hammers to press an inked ribbon against the paper

> Most common impact printer is the dot matrix

> Not usually letter quality (LQ)

> Many are near letter quality (NLQ)

> Used for multipart forms

Ink Jet Printer

•        Creates an image directly on the paper by spraying ink through tiny nozzles

•        Nozzles spray ink

•        Spray tiny drops of ink onto the paper

•        Both black-and-white and color

•        Resolution measured in dots per inch (dpi)

•        Speed measured in pages per minute (pap)

Laser Printer

•        A laser is at the heart of this printer that uses technology similar to that in photocopiers

> High-speed, high-quality nonimpact printer

> Very high quality resolution - 600dpi to 1,200 dpi

> Stores entire page before printing it

> Page description language (PDL)

> PCL (Printer Control Language)

> Postscript

> Toner

> Replace cartridge