Chapter 4- input and output
•Digital still cameras
-The primary appeal is that images are immediately available -Camera quality is measured in megapixels -Typically use flash memory for storage -Slight delay when taking photos
CRT Monitor
Output device. The older type of monitor, now almost obsolete. -Cathode ray tube (CRT) displays: large, bulky, and heavy
•Ink-jet printers
Type of printer in which the ink is sprayed onto the paper. spray droplets of ink to produce images on paper -Use ink cartridges -Usually print in color -Often the choice for home use -Relatively inexpensive with good-quality output -Print more slowly than laser printers -Potential applications for the future •Dispensing liquid metal, computer chips, "printing" human tissue, silk and protein ink, etc. -
mouse
a common pointing device that the user slides along a flat surface to more a pointer around the screen and clicks its buttons to make selections.
keyboard
a device used to enter characters at the location on the screen marked by the cursor. - can be built in, attached (by inserting a usb), or connected via wireless networking connection (bluetooth)
•3D printers
are unique in that they can create a three-dimensional object made of various materials. form output in layers to build a 3D version of the desired output -Can print using plastic, metal, ceramic, wood, glass, sugar, etc. -Additive manufacturing -Print customized objects on demand •Personal products •Medical products •Prototypes or custom parts •Can contain moving parts -Issues such as 3D-printed weapons
interferometric modulator
designed initially for phone devices and other portable devices an IMOD display is essentially a complex mirror that uses external light such as artificial and sun light instead of fighting it the way LCD displays do, images are brighter and clear even in direct sunlight.
portable scanners
designed to capture text and other data while on the go. some are full page digital scanners that capture images of an entire document others are handheld designed to capture text one line at a time.
Flatbed scanners
designed to scan flat objects on one page at a time, and they are the most common type of scanner. =work the same way photocopiers do
size
display device is measured diagonally
Scanners
input devices that capture printed images or documents and convert them into electronic digital signals (i.e., into binary representations of the printed image or document) that can be stored on computer media -Data is typically input as a single image -Can scan photos, documents, images, etc.
plasma display
layered tech. like LCD andOLED and look similar to LCD displays but they use a layer of gas between two plates of glass instead od liquid crystals or organic material.
high definition displays
most common HD format is 1080p, which uses a screen resolution of 1920 x 1080 and display screen images one line at a time -newest hd is Ultra HD (4K) which display progressive images using about 4x the pixels as 1080p.
printers
produce hard copy; that is a permanent copy of the output on paper. -Impact printers (dot-matrix) •Print mechanism strikes an inked ribbon to transfer ink to the paper •Used to produce multipart forms -Non-impact printers (ink-jet/laser) •Use liquid ink or toner •Produce higher quality images •Much quieter than impact printers -Can be color or black-and-white printers
wearable display
project images from smatphone or directly from the internet. -input -ex. smart glasses, such as google glasses are used by athletes, mobile workers, soliders and other individuals for hands free communications.
•Light emitting diode (LED)
semiconductor light source used in various applications; in the world of computers, LED technology is used to make optical mouses and LED displays displays use LCD panels and LED backlighting
Optical character recognition (OCR)
the capability of specialized software to interpret the actual letters and numbers on a page to create a digital document that can be edited, rather than a flat picture
Monitors
the display devices for a notebook, tablet, smartphone, smart watch, or other device for which the screen is built into the device is typically called a display screen.
display screens
the most common form of output device- presents output visually on some type of screen. -are built into a variety of devices •Notebook and other portable computers •Smartphones and mobile devices •Handheld gaming devices, home entertainment devices, kitchen appliances •Digital photo frames, e-book readers, smartwatches •Digital signage systems, digital billboards
•Voice input
the process of entering input by speaking into a microphone. -Inputting spoken words and converting them to digital form via microphone or headset -Used in conjunction with sound recorder software -Speech recognition systems enable the device being used to recognize voice input as spoken words •Can be used for dictation as well to as to issue commands to the device -Usually incorporated into smartphones, GPS systems, and other mobile devices
•Laser printers
use toner powder and technology similar to that of a photocopier to produce images on paper •The standard for business documents -Print one entire page at a time -Generally faster and have better quality output than ink-jet printers •Use toner cartridges; toner is transferred to the paper and fused with heat •Color printers use four toner cartridges
3D scanner
uses laser technology to create three-dimensional computer models
Characteristics of display screens
•Color vs. monochrome displays (configures in pixels, tiny dots on screen -Images are formed using pixels -Most displays today are color displays •CRT vs. flat-panel displays -Cathode ray tube (CRT) displays: large, bulky, and heavy -Flat-panel displays: take up less desk space; use less power
Keyboards for mobile devices
•Mobile devices often use: -Slide-out keyboard -Pen or touch input (on-screen keyboard) •Can use an external keyboard (stand-alone or built into a case)
stylist/pens
•Pen input is often used with mobile devices and tablets •Can be used with desktop and portable computers if the display screen supports it
print capabilites
•Personal vs. network printers -Personal printers connect directly to a single computer -Network printers connect directly to a home or an office network; some can perform cloud printing •Connection options -USB connection, wired network, Wi-Fi, Internet •Multifunction devices (MFDs) or all-in-ones -Copy, fax, scan, print
Printer characteristics
•Print resolution -Measured in dpi (dots per inch) or images per minute (IPM) -More dots per inch results in higher quality output -300 dpi for general purpose printing; 1,200 dpi for photographs; 2,400 dpi for professional applications •Print speed -Measured in pages per minute (PPM) -Range from about 15 to 65 ppm
Size, Aspect Ratio, and Screen Resolution
•Size and aspect ratio -Device size measured diagonally from corner to corner -Wide variety of sizes available -Most are wide-screen displays (16:9 aspect ratio) •Screen resolution -The number of pixels used on a display determines its resolution -Affects the amount of information that can be displayed on the screen at one time -Can be changed to match users' preference
Video Adapters, Interfaces, and Ports
•Video cards determine the graphic capabilities of a computer •VGA, DVI, and HDMI are the three most common interfaces to connect monitors to a computer •Ports exposed in the system unit cases connect monitors to computers -Newer option is to use USB ports
Digital Cameras
•take pictures and records them as digital images -Can be still cameras and/or video cameras -Integrated into portable computers, smartphones, and tablets - use a flash memory card, or built-in hard drive.
electronic paper display
A display used by e-book readers instead of LCD screens. An electronic paper display consumes less power and provides higher contrast in bright lighting than LCDs.
liquid crystal display (LCD)
A flat-panel monitor that creates an image when liquid crystals become electronically charged.
pointing device
An input device that moves an on-screen pointer, such as an arrow, to allow the user to select objects on the screen. are used to: -Select and manipulate objects -Input data -Issue commands to the computer •Common types: -Mouse -Pen/stylus -Devices that use touch input •
flat panel displays
Bring nearly theater-quality sound, color, and picture clarity to living rooms Smart-screen TVs: feature touch and gesture control and speech recognition
