Yuh-Jzer JoungOutput OUTPUT The Many Uses of Computing and Communications

Yuh-Jzer Joung Output

OUTPUTOUTPUTThe Many Uses of Computing

and Communications


Output Hardware

Hardcopy : Hardcopy refers to printed output Softcopy : Softcopy refers to data that is shown on a display

screen or is in audio or voice form.

Output Devices Display Screens Printers, plotters, multifunction, and microfilm / fiche devices Audio-output devices Video-output devices Virtual-reality devices Robots


Display Screen: CRTA CRT, for cathode-ray tube, is a vacuum tube used as a display screen in a computer or video display terminal. Images are represented on the screen by individual dots or “picture elements” called pixels. A pixel is the smallest unit on the screen can be turned on and off or made different shades.


Display Screen : Flat-panel Displays

Flat-panel are much thinner, weigh less, and consume less power. Thus, they are better for portable computer.

Substances between plates --- LCD and gas plasma – LCD consists of a substances called liquid crystal, the molecules of

which line up in a way that alters theirs optical properties. As a result, light --- usually backlighting behind the screen --- is blocked or allowed through to create an image .

– Gas plasma display is like a neon bulb, in which the display uses a gas that emits light in the presence of an electric current.

Arrangement of transistors --- active-matrix or passive-matrix – In an active-matrix display, each pixels on the screen is controlled by

its own transistor.– In a passive-matrix, a transistor controls a whole row or column of

pixels.


Flat-panel monitorsFlat-panel monitors

11,25, 1998


Screen Clarity Resolution: The clarity or sharpness of a display screen is called

its resolution; the more pixels there are per square inch, the better resolution. E.g., 640x480, 800x600, 1024x768, 1280x1024, 1600x1280.

Dot pitch : Dot pitch is the amount of space between the centers of adjacent pixels, the closer the dots, the crisper the image. E.g., .24mm, .27mm.

Refresh rate : Refresh rate is the number of times per second that the pixels are recharged so that their glow remains bright. Typical ranges from 50Hz to 150Hz.


Monochrome Versus Color ScreenMonochrome Versus Color Screen

Monochrome : Monochrome display screens display only two colors --- usually black and white, amber and black, or green and black.

Color : Color display screens can display between 16 and 16.7 million colors, depending on their type.


Text Versus Graphics :

Character-mapped : Character-mapped display screens display only text --- letters, numbers, and special characters.

Bitmapped: Bitmapped display screens permit the computer to manipulate pixels on the screen individually rather than as blocks.


Video Display AdaptersVideo Display Adapters

A video display adapter, also called a graphics adapter card, is a circuit board that determines the resolution, number of colors, and how fast images appear on the display screen.– VGA: VGA, for Video Graphics Array, will support 16 to 256

colors, depending on resolution.– SVGA: SVGA, for Super Video Graphics Array, will support

256 colors at higher resolution than VGA.– XGA: XGA, for Extended Graphics Array, support up to 16.7

million colors at resolution of 1024*768 pixels.


Hardware Output : PrinterHardware Output : Printer

Desktop Versus Portable Printers:– Desktop printers– Portable printers: transportable versus ultraportable

Impact Versus Nonimpact Printers:– Impact Printers

• Dot-matrix– Nonimpact Printers

• Laser printers• Inkjet printer• Thermal printer


Impact Printers

An impact printer forms characters or images by striking a mechanism such as a print hammer or wheel against an inked ribbon.

The right is a Dot-matrix printer


Inkjet Printers ( 噴墨印表機 )Inkjet printers spray small, electrically charged droplets of ink from four nozzles through hotels in a matrix at high speed onto paper.


雷射印表機


Page Description Languages

• A page description languages describes the shape and position of letters to the printer.

Two common page description languages:• PostScript• PCL (Printer Control Language)


Laser printer ( 雷射印表機 )A laser printer uses the principle of dot-matrix printers in creating dot-like images. However, these images are created on a drum, treated with a magnetically charged ink-like toner (powder), and then transferred from drum to paper.


Thermal printer


Hardware Output : PlottersHardware Output : Plotters Pen plotter : A pen plotter is designed so that paper lies flat on a

table-like surface (flatbed plotter) or is mounted on a drum (drum plotter). Between one and four pens move across the paper, or the paper moves beneath the pens.

Electrostatic : An electrostatic plotter uses electrostatic charges to create tiny dots on special treated paper. The paper is then run through a developed to produce the images, which may be four-color.

Thermal plotter : A thermal plotter uses electrically heated pins and heat-sensitive paper to create imaged.


PlottersPlotters


Multifunction Technology:Multifunction Technology: Printer that do more than print

Multifunction machines combine several capabilities, such as printing, scanning, copying, and faxing, all in one device.

Computer Output Microfilm/fiche is computer output produces as tiny images on rolls/sheets of of microfilm.

The paper Glut :Whither the “Paperless Office”?


Audio-output Devices Voice-output devices: Voice-output devices convert digital data

into speech-like sounds. Two types of voice-output technology:– Speech coding uses actual human voices speaking words to provide

a digital database of words that can be output as voice sounds.– Speech synthesis uses a set of 40 basic speech sounds (called

phonemes, the bases of all speech in English) to electronically create any words.

Sound-output devices: Sound-output devices produce digitized sounds, ranging from beeps and chirps to music.


視訊會議 (videoconferencing)


Video-output Devices Videoconferencing and video editing: Videoconferencing is a

method whereby people in different geographical locations can have a meeting --- and see and hear one another --- using computer and communications.

HDTV: HDTV(High-definition television) is a television system that features enhanced video and crisp, clear picture using digital transmission.


Virtual-Reality and Simulation

¤ Headgear:The headgear has two small video display screensthat create the sense of 3-D.

¤ Glove:The glove has sensors that collect data about your handmovements.

¤ Software:Software gives the wearer of this special headgearand glove the interactive sensoryexperience.

Virtual reality (VR) is a kind of computer-generated artificial reality that projects a person into a sensation of three-dimensional space.


虛擬實境系統


RobotsRobots

A robot is an automatic devices that performs functions ordinarily ascribed to human beings or that operates with that appears to be almost human intelligence.


RobotsRobots


Creative Output :Creative Output : The Manipulation of Truth in Art & JournalismThe Manipulation of Truth in Art & Journalism

Preview & Review : Users of information technology must weigh the effects of the digital manipulation of sound, photos, and video in art and journalism.

Manipulation of Sound Manipulation of Photos(right

picture) Manipulation of Video


The Future of Output

Preview & Review : On the horizon are better, cheaper, and lager display screens; higher-fidelity audio using wave-table synthesis and three-dimensional sound; and real-time video using digital wavelet theory. 3-D technology is bringing three-dimensionality to computer displays and, through VRML (Virtual Reality Markup language) software, 3-D ”virtual worlds” to user of the World Wide Web.

Display Screens : Better & Cheaper Audio : Higher Fidelity Video : Movie Quality for PCs Three-dimensionality Display Virtual world : 3-D in Cyberspace


3-D 顯示


視訊會議示意圖

Documents

Yuh-Jzer JoungOutput OUTPUT The Many Uses of Computing and Communications