| Answer | Correct Statement |
| 1. T | Output
is data that has been processed into a useful form.
Output is data sent to an output device. [Usefulness is not necessarily included in this definition.] |
| 2. F | Information
on an electronic display device is sometimes called soft copy.
[The book wanted you to answer "soft copy". You could reasonably argue that a "display device" includes printers, and therefore "hard copy" is correct.] |
| 3. T | A video card converts digital output from the computer into an analog video signal. |
| 4. F | A flat panel display is a display with a shallow depth that does not use CRT technology. |
| 5. F | A pixel (picture element) is an addressable location in an electronic image. |
| 6. T | A line printer is a high-speed impact printer that prints an entire line at a time. |
| 7. T | A photo printer is a color printer that produces photo-lab-quality pictures. |
| 8. F | A thermal printer generates images by pushing electrically heated pins against heat-sensitive paper. It is a non-impact printer. Basic thermal printers are inexpensive, but the print quality is low and the images tend to fade over time. |
| 9. T | With Bluetooth printing, a device transmits output to a printer via radio waves according to the Bluetooth standard. |
| 10. T | A fax modem transmits computer-prepared documents or documents that have been digitized with a scanner or digital camera. |
| 11. T | A multifunction peripheral is a single device that looks like a copy machine but provides the functionality of a printer, scanner, copy machine, and perhaps a fax machine. |
| 12. T | Force feedback is a technology that sends resistance to the device in response to actions of the user. |
1a. What features do CRT monitors usually include to address ergonomic issues?
A feature is "ergonomic" if the purpose is to increase the safety, efficiency, or comfort of the user, beyond providing the basic function of the device. Some properties have been advertised as "ergonomic" for the purpose of marketing and political appearance of considering the Americans with Disabilities Act of 1990, when the motivating design consideration was primarily with respect to basic device functionality.
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Place the system unit at a location different from the monitor. This permits the monitor to be at eye level or below eye level. This greatly reduces neck strain. The top of the screen should be at eye level. The bottom of the screen should be less than 30 degrees below eye level. |
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Detach the CRT from the keyboard, making them separate units. In the early 1980s, keyboard and monitor was combined as a unit called a "terminal". |
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Provide the monitor with a swivel base. This reduces neck and eye strain strain by allowing the screen to be perpendicular to the line of sight. With the monitor |
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A flat screen can help reduce glare. However, it increases image distortion as a function of distance from the display center. |
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Use smaller phosphor particles on the inside envelope of a CRT, or smaller crystals in an LCD display, decreasing dot pitch. This makes images more well-defined, and therefore reduces eye strain. |
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Use a refresh rate greater than the Critical Fusion Frequency. This reduces the percentage of population that perceive flicker. |
Some other features that have been claimed "ergonomic" may have a secondary effect of improving efficiency or comfort of the operator.
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Increasing the refresh rate to 75 Hz or more. Merely increasing the refresh rate to 75 Hz was part of the design requirements for using a lower persistence phosphor to achieve a more dynamic display for viewing rapidly changing images. The motivation was not for the safety, efficiency, or comfort of the user, and hence not truly an ergonomic feature. Calling it "ergonomic" has been used in marketing to increase sales. |
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Astigmatism, contrast, brightness, vertical and horizontal extent controls adjust the sharpness and size of the viewable area, which decreases eye strain. These are basic functional features included in the design without regard to safety, efficiency, or comfort of the user, and hence are not normally considered an ergonomic feature. |
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Digital controls for astigmatism, contrast, brightness, vertical and horizontal extent, etc, are not for "ergonomic" reasons. Rotation controls work with equal or greater ease. Making such controls digital opens up the possibility of efficient remote control, and establishing a library of preset conditions. Remote control could be useful in an operating room where a surgeon is viewing a display, but the display image quality is controlled by another person not immediately around the patient. |
1b. What is the Energy Star program?
The Energy Star program goal is an environmental protection program to reduce the use of electrical energy. It requires a main power saving mode that consumes less than 30 watts.
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One approach is to turn off the electron guns in a CRT when the computer keyboard and mouse have been idle after a predetermined amount of time. A CRT uses about as much electricity as three or four 100 Watt light bulbs. Compliant monitors operate under the control of the operating system. Windows allows you to set the time lapse before the screen goes dark. This also is better than a screen saver for preventing spot burning on a monitor. In addition to consuming less power directly, less energy is needed in the summer for air conditioning, since a CRT generates a significant amount of heat. |
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Another approach is to use an LCD display, which uses significantly less power than a CRT. |
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Energy conservation is also being implemented in many system units. Some computers will turn the motor of the hard disk off after a significant amount of no activity by the keyboard or mouse. This time lapse can be set by the user. |
2a. How is an active matrix display different from a passive-matrix display?
Click here for a tutorial on liquid crystal display technology.
Answer: A passive matrix display addresses a pixel by a grid of horizontal and vertical wires. The selected LCD pixel either blocks light or allows light through. The passive matrix display relies on persistence to maintain the image until the pixel is refreshed.
Unlike the passive matrix display, the active matrix display uses a separate (thin film) transistor for each pixel to maintain its state between scans. The active matrix display uses more power than the passive matrix display.
2b. What is organic LED (OLED)?
"An organic semiconductor may be defined as a solid containing an appreciable number of carbon-carbon bonds which is capable of supporting electronic conduction." J. J. Brophy, "Introduction", Organic Semiconductors: Proceedings of an Inter-Industry Conference, James J. Prophy and John W. Buttrey (editors), Macmillan Co. (1962).
An Organic Light Emitting Diode (OLED) is an organic material that has the conductivity of metals that is based on a class of plastic materials called conjugated polymers. "The basic OLED cell structure consists of a stack of thin organic layers sandwiched between a transparent anode and a metallic cathode. The organic layers comprise a hole-injection layer, a hole-transport layer, an emissive layer and an electron-transport layer. When an appropriate voltage (typically a few volts) is applied to the cell, the injected positive and negative charges recombine in the emissive layer to produce light (electroluminescence)." OLEDs can be used in a passive or active matrix display. Unlike LCDs, "there are no intrinsic limitations to the pixel count, resolution, or size of an active-matrix OLED display." The fabrication process is simpler. "The two main Achilles heels of OLED development: poor efficiency and short lifetime." PC Tech Guide http://www.pctechguide.com/07pan3.htm (29 December 2004)
3a. What advantages do digital television signals provide over analog signals?
Digital transmission of compressed data offers greater number of programs to the consumer than available using traditional TV transmission standards. Encryption preserves the entertainment industry profits.
An HDTV signal is initially an analog image. When you digitize, you lose information. It is not possible to NOT lose information. The TV standard adopted a format that is compatible with early transmission technology. The digital approach allows us to remove data to compress the signal, allowing adequate quality and reconstruction.
If a new all-analog standard were established, that could also produce a format that exceeds current NTSC quality. In principle, such an analog signal could be band-limited and multiplexed to achieve transmitting a large variety of programs via optical fiber. Likewise, you can scramble an analog signal and recover it, if you are sufficiently careful.
It is easier to recover compressed and encrypted digital signals than analog signals. You do not need as tight quality control. You do not need to worry as much about components drifting out of calibration.
The question should have compared HDTV versus NTSC rather than HDTV versus analog.
3b. What is interactive TV?
Interactive TV is a digital cable TV service that uses full duplex communication in which customers interact with services provided by the television broadcast company. It allows customers to watch TV while also seeing web content associated with the television program, rather than competing with or distracting from the TV program.
Customers may select predetermined television programs, respond to polls and questions as a television audience, television programs modified by interactivity, television programs assembled by viewer from several broadcast signals, remote live classes, news, email, weather, instant messaging, chat, multiplayer games. Interactive TV supports digital set-top boxes. Vendors include Cablevision.
4a. How is portrait orientation different from landscape orientation?
These terms allude to how you would hold a camera when taking a picture of these different objects. A portrait of one person is usually taken with the vertical dimension longer than the horizontal dimension. For this reason, such a choice is called portrait orientation. Similarly, when you take a picture of a landscape, you usually hold the camera to capture the largest horizontal extent possible. This is called landscape orientation, with the horizontal dimension longer than the vertical dimension.
4b. What is continuous form paper?
Continuous form paper is a very long sheet of paper that is either perforated and fan-folded into sheets in a box, or unperforated on a roll. Usually, such paper has edges with holes spaced closely apart to engage sprockets that control the motion of paper through the printer. That paper control system is often called "tractor feed". Continuous form paper is used with line printers, drum plotters, and most dot matrix and shuttle matrix printers. Paper for small electrostatic or heat sensitive calculator printers are continuous form without the tractor-feed holes.
5a. What is a page description language?
A page description language (PDL) is a language that is used to tell printer software how to lay out the contents of a printed page. Hewlett-Packard's Printer Command Language (PCL) and Adobe's PostScript (PS) are examples. PCL is used on HP laser printers, and is common in home and business settings. PS is used more often in a UNIX environment, often associated with the academic world in science and engineering. PS had an early boost as a result of a program (DVIPS) that translated TeX output files called Device Independent files (DVI) into PostScript. TeX has been, for years, the typesetting language of choice for science, mathematics, and engineering. Because of the need for computer-generated plots and graphics in science and engineering, PS was developed to have robust capability in this area. Much of the cutting edge documentation in science and engineering is available in PS files. Such files are now even more portable, thanks to the Acrobat Reader software now accepting PS files.
5b. How is PCL different from PostScript?
The text reports that PS is used in desktop publishing and graphic art fields because it is designed for complex documents with intense graphics and colors.
The History of PostScript. http://www.prepressure.com/ps/history/history.htm (29 December 2003). PostScript is a scale or resolution independent page description language. Its files will print well at 300 dpi or 2400 dpi, without changing the file. It was developed in 1984 and became the industry standard prepress typesetting computer language. It supports image decompression, and it supports composite fonts needed for idiographic languages. PostScript 3 supports Adobe PDF files and Web-ready printing.
HP Color LaserJet and LaserJet Series Printers - History of Printer Command Language (PCL). http://www.hp.com/cposupport/printers/support_doc/bpl04568.html (29 December 2003). HP PCL was created originally for HP dot matrix and ink jet printers. PCL 3 was released in 1984 for the HP LaserJet printer. HP PCL formatters and fonts are designed to quickly translate application output into high-quality, device-specific, raster print images. PCL 5, released in 1990, implemented font scaling, outline fonts and HP-GL/2 (vector) graphics.
1.b. What is a gas plasma monitor?
Answer: Initial gas plasma display technology excited neon sandwiched between glass panels to fluorescence by using a transistor to pass an electrical current through neon at a particular pixel location. A simple explanation is given at the United Visual web site, http://www.unitedvisual.com/2tips/2tpls102.asp
Sharp Electronics produces a gas plasma display that uses a combination of neon gas and phosphors to produce a color image. http://www.kipinet.com/mmp/mmp_apr96/dep_techwatch.html . Common large display sizes for are in the 40-inch to 50-inch range, priced in the $10,000 range. Large displays have been on Aegis cruisers in the Navy for over a decade, and also at Times Square in New York City.
2.a. How do Liquid Crystal Display (LCD) monitors and LCD displays present information on the screen?
Answer: LCD monitors and LCD displays use liquid crystal, instead of a cathode ray tube, to present information on the screen. A liquid crystal changes shape when an electric current is passed through it. This permits light from a back-lit display to pass through, or reflects light from a front-lit display, depending on the design of the display.
2.b. What is a flat panel display?
Answer: A flat panel display is a compact flat that requires much less room than a cathode ray tube display. LCD and gas plasma displays are examples of flat panel displays.
2.c.1. What is an electronic book (e-book) [buzz...]?
Answer: An electronic book is a small, book-sized computer that allows a user to read, save, highlight, bookmark, and add notes to an online text. You download new book content to your electronic book from the Web. An electronic book can be read with Acrobat, or with Microsoft Reader which uses ClearType.
2.c.2. How does an electronic book use ClearType?
The text does not tell you HOW an electronic book uses ClearType. It only says that the goal is to make on-screen reading as natural as reading from printer material.
Microsoft says the goal is to make makes text viewed on liquid-crystal displays (LCD) appear sharp. http://www.microsoft.com/typography/cleartype/default.htm?fname=%20&fsize= 21 SEP 2001
For a description of ClearType technology, see John
Platt, "Technical
Overview of ClearType Filtering
3.a. What is high-definition television (HDTV)?
Answer: HDTV is a new standard for television. It includes specifications for resolution and transmission format. It offers increased resolution, wide screen format, and digital transmission of data. There are two transmission formats, each with their own advantages. The United States uses 8-VSB. All TV transmissions in the United States will be HDTV by the year 2006. COFDM is used in Europe.
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“8-VSB” is 8-Level Vestigial Sideband. (1996) 8-VSB is less affected by impulse noise from household appliances. It has a lower cost of construction and operation. It makes more efficient use of the spectrum. It has a "ghosting" problem in large cities. |
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“COFDM” is Coded Orthogonal Frequency Division Multiplex. This is better for mobile use, including reflection off moving objects, vehicles, or rain. |
A discussion about the merits and demerits of government involvement in HDTV standards development can be found at http://www.cato.org/pubs/regulation/reg16n4b.html .
4.a. What is monitor ergonomics?
Monitor ergonomics is the conscious design of a monitor incorporate comfort, efficiency, and safety.
4.b. Why is monitor ergonomics important?
Ergonomics is important in 2002 because it is politically correct. The more rational justification for considering ergonomics is to increase worker productivity through thoughtful equipment design. Safe, comfortable, healthy workers can produce more work per unit time.
Today, there is a glut of people making workmen's compensation claims for carpal tunnel syndrome due to computer keyboard usage. By making keyboards too comfortable, convenient, and compact, worker's extremities use less range of motion, and repeat motion frequently within a limited range of motion. Have we crossed a trade-off point where we are causing more problems than we are solving by placing an emphasis on comfort and convenience?
5.a. How is a dumb terminal different from an intelligent terminal?
Answer: A dumb terminal has no processing capability. A host computer performs all required operations. Dumb terminals are often used with main frame computers.
An intelligent terminal has a processor and memory, and can perform some functions independent of a host main frame computer.
Intelligent terminals often emulate a dumb terminal when connected to a supercomputer.
5.b. For what purpose is a point-of-sale terminal used?
Answer: A point of sale terminal records purchases at the point where the consumer purchases a product or service. A point-of-sale terminal is a cash-register connected to a computer. It is designed to make the purchase process fast, and often also to collect data for inventory control and accounting. It often has special keys with overlays to help new cashiers with minimal training to accurately record customer selections. It might have one or more bar code scanners, weighing scales, a credit card reader, and a keypad for customer use.
More about displays can be found at:
Raytheon Digital Display Group: http://www.raydisplays.com/displays/html/technology/index.html
5.c. What is a programmable terminal?
A programmable terminal is another name for an intelligent terminal. It can be programmed to perform basic tasks. More importantly, it can be reprogrammed.
1.a. How are color monitors, monochrome monitors, and monitors that use gray scaling different?
Answer: The monitors differ by the rare earth phosphors used to coat the inside of the glass envelope of the CRT and the number and control of the electron beams used to excite these phosphors. An increase in the number of intensity levels and an increase in the number of beams requires more bits per pixel to provide the information, greater number of steps in associated digital-to-analog converters, and higher quality control circuits.
Typical color monitors for microcomputers are coated with triads of red, green, and blue phosphor dots of medium persistence. Monochrome monitors typically use amber, green, white, or sometimes blue phosphors.
Use of discrete levels of intensity on a monochrome monitor is called gray scaling. The generalization of this concept to color monitors gives us variety in intensity of colors and their mixtures yielding other colors.
1.b. When are color monitors and monochrome monitors most widely used?
Answer: Monochrome monitors are used for display for data entry applications that do not require graphics. Color monitors are used for home entertainment, science, engineering, and office productivity applications.
4. a. How is hard copy different from soft copy?
Answer: The classification of output as hard copy versus soft copy is to contrast printed output versus monitor-displayed output. Hard copy output also includes microfilm, microfiche, and other permanent formats that can be viewed without use of electronic devices. Permanence of information does not itself classify it as hard copy. For instance, data burned into a ROM or onto a CD-ROM is not usually referred to as hard copy. Soft copy output usually refers to visual display of data that is subject to change, such as residing on a disk, tape, or perhaps only in RAM.
4. b. How is portrait orientation different from landscape orientation?
From old Chapter 13, but on the topic of new Chapter 6:
4a. What are two types of data projectors?
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Liquid Crystal Display (LCD), and |
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Digital Light Processing (DLP). |
4b. How are they different?
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Liquid Crystal Display uses its own light source to display information shown on the computer screen. Most LCD projectors require an NTSC converter. NTSC is the National Television System Committee. |
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Digital Light Processing projector uses tiny mirrors to reflect light, producing crisp, bright, colorful images that remain in focus and can be seen clearly even in a well-lit room. DLP projectors can display SVGA output directly from the computer. |