Output devices

Course:

MAM SADAF

MBA 1st Semester

Class:

Course instructor:

Out Put Devices

1. Mirza Sajid Mahmood

2. Haris Javed

Any peripheral that presents output from the computer, such as a screen or printer

OUTPUT HARDWARE:

Types of Output:There are two types of Output that are mentioned below1. Softcopy2. Hardcopy

1. Softcopy:Softcopy is data that is shown on a display screen or in audio or voice form; it exists only electronically.This kind of output not tangible.

2. Hardcopy:Hardcopy is printed outputi.e. Printouts (Text or graphics) from PrintersHardcopy’s are tangible

Traditional Softcopy output: Display Screens (Monitor)

Display screens also variously called monitors or simply screens are output devices that show programming instructions and data

•Computer screen is measured by diagonally from corner to corner in inches• Monitors are available in size 14 to 24 inches• For Laptop screen size are 12 to 17 inches

Viewable Image Size (VIS):Computer ads state the actual display area are called Viewable image size (VIS)

•VIS in 15 inch monitor may have 13.8 inch• VIS in 17 inch monitor may have 16 inch

Factors affecting Screen clarity (Features):Factors affecting screen clarity are mentioned below

1. Dot Pitch2. Resolution3. Color Depth4. Refresh Rate

These relate to the individual dots on screen is known as pixels, which represent the images on screen

Pixels:A pixel for “picture element” is the Smallest unit on the screen that can be turned on and off or made different shadesPixels are tiny squares not circle

1. Dot Pitch (dp)Dot Pitch is the amount of space between the Centers of adjacent pixels

pixels

Dot Pitch

2. Resolution:Resolution refers to image sharpness of the displayScreen; the more pixels, or dots, there are per square inch, the finer the level of detail.

Resolution clarity is measured by formula (Horizontal row Pixels) x (Vertical row Pixels)For example: 1024 x 768 screen display ( 1024 pixels in 768 lines total 786,432 pixels)

3. Color Depth:

4. Refresh Rate:Refresh rate is the number of times per second that the pixels are recharged so that their glow remains brightGeneral Display Refreshed 56-120 times per secondGeneral Display Refreshed 70-87 Hertz

Color depth or bit depth is the amount of information expressed in bits, that is stored in a dots24 bit color depth mean each primary color (Red, Green & Blue)

Types of Monitor:There are two types of monitor or display screen

1. Cathode-Ray tube or CRTs:

1. CRTs2. Flat Penal

It is a vacuumed tube used as a display screen in a computer or video display terminal

2. Flat Penal:They are made up of two plates of glass separated by a layer of a substance in which light is manipulated

There are two types of flat penal technologiesA. Liquid Crystal display (LCD)B. Organic Light Emitting Diodes (oLED)

A. Liquid Crystal Display:LCD, in which molecules of liquid crystal line up in a way that alters their optical properties, creating images on screen by transmitting or blocking out light

organic light-emitting diode, a display device that sandwiches carbon-based films between two charged electrodes, one a metallic cathode and one a transparent anode, usually being glass

B. Organic Light Emitting Diodes:

3. Ultra Extended Graphics Array(UXGA)4. Quantum Extended Graphic Array(QXGA)5. Wide aspect Extended Graphics Array(WXGA)

1. Extended Graphics Array:

XGA has a resolution up to 1024*768 pixels with 65536 possible colors. Its used in 15” & 17" CRT monitors.

Resolution Standard for MonitorThe picture quality of a display screen is known as

resolution

1. Extended graphics Array(XGA)2. Super Extended Graphics Array (SXGA)

2. Super Extended Graphics Array:It has a resolution up to 1280*1024 pixels. Its used

in 15" LCD

3. Ultra Extended Graphics Array:It has a resolution up to 1600*1200

pixels and support up to 16.8 million colors. Its used with 1280*1024 15” &17” CRT monitors and 17 & 19” LCD

It has a resolution up to 2048*1536 pixels. Its used in large LCD screens for computer users to view extreme detail in advancer graphics

4. Quantum Extended Graphics Array:

5. Wide Aspect Extended Graphics Array:It has a resolution up to 1366*768 and

WUXGA 1920*1200 its used in HDTV’s and HD movies with wide screen note book computers

PrintersIts an output device that prints characters, symbols, and perhaps graphics on paper or

on another hardcopy medium.

Kinds of printers Impact printersAn impact printer forms characters or images by striking a

mechanism such as a print hammer or wheel against an inked

ribbon leaving an image on paper.

Nonimpact printers It forms characters and images without direct physical contact between the printing mechanism and paper.

Types of Impact printersDot matrixThese printers print each character as a pattern of dots. They

produce a draft quality a coarser looking 72 dpi or near latter

quality(NLQ) a crisper looking 240 dpi.

Daisy wheelAlso known as letter quality use a printwheel font. Each

wheel has a character embossed on it. The speed normally

ranges 10-50 characters per second.

Line printerThey are most medium and large computers with a speed

ranging from 300 lines to 2500 lines per minute. The output

efficiency can be increased with multiple part papers

(carbon papers) for more than one copy.

Types of Nonimpact printersLaser printer It creates images with dots. However as enough as in a

photocopy machine these images are produced on a drum

treated with a magnetically charged ink like toner(powder) and

then transferred from drum to paper. They are also called page printers.

Inkjet printersThey spray on the paper small electrically charged droplets on

ink from four nozzles through holes in a matrix at high speed.Thermal printersThey are low to medium resolution printers that use a type of

coated paper that darkens when heat is applied to it.

Other types of printersPhoto PrinterThey are specialized machines for printing continuous tone

( typically 3*5” & 4*6”).

PlottersThey are a specialized output device designed to produce

large high quality graphics in a verity of colors. Multifunction printerMulti functions printers combine several capabilities such

as printing, scanning, copying and faxing.Specialty PrinterThey are special purpose printers for specific tasks like

printing tickets, labels etc

Audio & Video output devices

Audio output deviceAudio output devices produce digitized sounds ranging

from bits and chirps to music.

Voice output deviceVoice output device converts digital data into speech like

sound

Video output deviceVideo consists of photographic images which are played at

15-19 frames per second to give the appearance of full motion.

Video ConferencingPeople in different geographic locations can have a

meeting, can see and hear one another using computers

and communications.