4 Monitor Overview The most-used output device on a computer. Most desktop displays use a cathode ray tube (CRT).Laptops use liquid crystal display (LCD), light-emitting diode (LED), and gas plasma or other image projection technology.Monitors using LCD technologies are beginning to replace CRT.It provides instant feedback by showing text and graphic images.Due to the slimmer design and smaller energy consumption LCDs are starting to replace CRTs on many desktops.
5 LCD HistoryLiquid crystals were first discovered in 1888 by Austrian botanist Friedrich Reinitzer.Melt cholesterol-like substance.When cooled, the liquid turned blue before finally crystallizing.RCA made the first experimental LCD in (1968).Manufacturers have been developing creative variations and improvements since on LCDs.
6 What is Being Used Today? The most popular display today remains CRT.It has been available for more than 70 years.CRTs:Vivid colors and detailed images and text.Cost less than LCD monitors.Continue to evolve.
7 LCD Market TrendMarket for flat screen LCDs grew rapidly during the ‘90s.Huge success of the laptop computer.It has still been slow in matching the market share of the CRT.Color LCDs hit the market in the early ‘90s.Has only now become popular enough for vendors to mass-produce.
8 From CRT to LCD CRT LCD Bulky, heavy, use vacuum tube technology. Using technology that was developed in the 19th century.LCDFirst LCD laptop monitors were very small due to manufacturing costs.Light, sleek, energy-efficient, have sharp picture.
9 How Monitors Work Most use a cathode-ray tube as a display device. CRT: Glass tube that is narrow at one end and opens to a flat screen at the other end.Narrow end contains electron guns.Single gun for monochrome and three guns for color.Display screen is covered with tiny phosphor dots that emit light when struck by the electron gun.
10 Monitor Classifications Monochrome: Display two colors, one for the background and one for the foreground.Gray-Scale: A special type of monochrome monitor capable of displaying different shades of gray.Color: Can display anywhere from 16 to over 1 million different colors. Sometimes called RGB monitors.
11 Monitor Quality and Resolution Manufacturers describe quality by dot pitch.Smaller dot pitches mean pixels are closely spaced which will yield a sharper image.Most monitors have dot pitches that range from 0.22mm to 0.39mm.Resolution:Indicates how densely packed the pixels are.Most modern monitors can display 1024x768 pixels.High end models can display 1280x1024.
12 LCD TechnologyUsed for displays in notebooks, small computers, pagers, phones and other instruments.Uses a combination of fluorescent-based backlight, color filters, transistors, and liquid crystal to create and illuminate images.Until recently, was only used on notebook computers and other portable devices.In 1997, manufactures began to offer full size LCD monitors as alternatives to CRT monitors.
13 IBM Advances in Display Technology In 1981, IBM introduced the Color Graphics Adapter (CGA) display, able to display 4 colors and max resolution of 320x200.In 1984, Enhanced Graphics Adapter (EGA) display, able to display 16 colors and resolution of 640x350.
14 IBM Advances in Display Technology (cont.) In 1987, Video Graphics Array (VGA) display.Most computers today support the VGA standard.In 1990, Extended Graphics Array (XGA) display, capable of resolutions 800x600 in true color ( 16.8 million colors) and 1024x768 in 65,536 colors.
15 Pre-IBM Apple II Released in 1977 First true “personal computer” Based on the Apple I design with some additionsPlastic caseAble to display color graphicsAble to display 6 colors at 280x192 resolution.
17 Pre-IBM (cont.) TRS-80 Developed in late 1970s by Radio Shack. First product in store history to fetch more than $500.Monitor was basically an RCA TV with the tuner removed.Became a direct competitor to the Apple computer.
19 Heath DesktopOne of the first computers designed as complete desktop machines.Included monitor, floppy disks and keyboard.Was eventually bought by Zenith.
20 IBM PC-1981 IBM’s 5150 model introduced in 1981. The PC featured a 5-MHz Intel processor, 18K of memory and an optional color monitor.Starting price: $1,565
21 Windows Screen Shots Throughout Time: MS-DOSWindows 3.1
22 Windows Screen Shots Throughout Time: Windows 2K
23 Windows Screen Shots Throughout Time: Windows XP
24 Advantages of LCDs Physical Size Compact and Lightweight Space saving Can be mounted on a wall or panel
25 Advantages of LCDs Display Size Available at comparable in screen size as traditional CRTShown on the next slide, a 12.1" LCD display (left) has only a slightly smaller viewing area than a typical 14" CRT monitor. Newer, larger LCD monitors are also appearing that have 15", 17", and even larger screen sizes that are comparable to the largest CRT monitors. (One thing to note is that LCD monitors are typically sized by their actual viewable diagonal measurement, but CRTs typically are not.)
27 Advantages of LCDs Power Consumption and Radiation Emission Consume less energy and more durableA typical CRT losses approximately 50% of its brightness after 10,000 hours. An LCD bulb will maintain its brightness anywhere from 25,000 to 50,000 hours.LCD consumes fewer watts than a CRT. LCD will use an average 30 watts compared to 120 watts for the CRT.Can reduce electric bill by 40-85%.Uses a combination of fluorescent-based backlight, color filters, transistors, and liquid crystal to create and illuminate images. It blocks light rather emit light
28 Advantages of LCDs Power Consumption and Radiation Emission Doest not emit RadiationNot subject to Electromagnetic Interference
29 Advantages of LCDs Viewing Cause less eyestrain Does not flicker or glare(Source: Dailey News – June 2, 2002, TouchScreens.com, unicomplabs.com, TheVisualLink.com)
30 Advantages of CRT Color Resolution Most are capable of displaying unlimited colors.ResolutionMultiple video Resolutions.
31 Advantages of CRT Response Time Faster response time. Critical to people who watch videos or play games on their PC’s.The fastest LCD’s offer a response time of about 25 milliseconds as apposed to CRT’s that have a response time of about 13 milliseconds.
32 (Source: PCWorld.com, TouchScreens.com) Advantages of CRTViewing Anglea very wide angle(Source: PCWorld.com, TouchScreens.com)
33 Disadvantages of LCDs Resolution Viewing Angle Displays Native Resolutions (Resolution that it displays best)Viewing AngleSmaller, needed to be viewed more directly from the front.From the side the images on an LCD screen can seem to disappear, or invert colors.Newer displays that are coming out have a wider viewing angle so this is not as much of an issue as it has been in the past.
34 Disadvantages of LCDs Price Upfront cost it is more costly but long-term cost but will conserve energy in the long run.The energy savings may not be much for an individual use, but for a corporate office where 50 displays or more are in use, the energy savings might be more of an issue.
35 Disadvantages of LCDs Installation Need a plug interface to connect to the computer.Some require a special digital plug-interface in order to work .Problem: is that this plug is not available on most computers, so another video card or adapter must be purchased to plug these LCD monitors into the computer.
36 (Source: TechRepublic.com, PCWorld.com, TouchScreens.com) Disadvantages of LCDsResponse TimeIt is much slower. The delay can cause a ghosting effect on images it displays.(Source: TechRepublic.com, PCWorld.com, TouchScreens.com)
37 (Source: TechRepublic.com) Disadvantages of CRTsPhysical sizeTakes more desktop space.(Source: TechRepublic.com)
38 (Source: TechRepublic.com) Disadvantages of CRTsPower Consumption and Radiation EmissionConsumes more energyEmits harmful radiation. The metal shield behind the glass of your monitor protects your body from a flood of radiation.It holds a dangerous electrical charge even after turned off and can last up to several years and be hazardous and even deadly to anyone who opens a CRT monitor casing.Know to cause fires due to electrical malfunctions and excessive heat if the ventilation holes are accidentally covered up.(Source: TechRepublic.com)
39 Current Technology and Trends CURRENT LCD’sCurrent Technology and Trends
40 Business Aspect Reasons for a sensitive market: I. Price sensitive demand – As price dropsslightly sales go up sharply.II. Long time for production facilities toform.
41 Recent History 1999 – Very high demand for LCD 2000 – Crash of computer market causessurplus.Prices are slashed.
42 Average 17” LCD Monitor Street price QuarterAverage Price1Q 2001$1,1482Q 2001$1,0033Q 2001$8874Q 2001$7811Q 2002$7732Q 2002$7573Q 2002$7354Q 2002$676Average 17-inch LCD monitor street price.
43 Technology Aspect 1. Display addressing. 2. Analog VS digital signal handling.3. Display Uniformity and Viewing Angle .
44 Active VS. Passive Display Active DisplayPassive Display
46 Analog VS Digital signal handling On most graphic card signal goes through DAC (digital to analog converter) to convert to Analog signal.LCD must convert the signal back to digital to determine which pixel to light.If conversion has error the result is "pixel jitter", in which the image seems to shimmer or move.
47 Improved Signal Handling 1. DVI (digital video interface) standardwas adopted.i. DVI handles both analog and digitalsignals with separate connectors2. controlling circuitry became substantially better in a very short time.
48 Display Uniformity Backlight Early LCD backlight wasn’t uniform and “hot spots” were created.Display manufacturers developed more sophisticated diffusing materials.
49 Viewing AnglesImproving Viewing angels can be done by changing cell design.Three different cell designs.1. Vertical alignment (VA).2. In-plane switching (IPS).3. Multi-domain.
51 Short & Long Term Prices 3 Important Ergonomic Features LCD Future TrendsShort & Long Term Prices3 Important Ergonomic FeaturesLCD Monitor QualityNew TechnologiesShort & Long Term Prices3 Important Ergonomic FeaturesLCD Monitor QualityAnd Some New Technologies
52 LCD Future Trends Lower LCD Prices in the Short Term The Dock Works StrikeThe Slow EconomyMore Factories Online
53 LCD Future Trends Lower Prices in the Long-Term Calculators, CRTs, VCRs and DVD Players were all very expensive at firstThey now sell at lower prices because of the laws of supply and demandWhat do they have in common with LCDs?The are all electronic devicesSo if the laws of supply and demand continue to apply, LCDs will sell for less in the long-term
54 LCD Future Trends Lower Prices in Long-Term (continued) Example of an LCD going down in priceIBMs T220 LCD monitor cost about $50,000 when it first came outOct 2001 – it costs: $22,000Dec 2001 – it costs: $15,999May 2002 – it costs: $8,400 (T221)
55 LCD Future Trends Three Important Ergonomic Features Large Viewing AnglesAll LCDs approaching 170° both horizontal & verticalMinimal Reflection and GlareSharp’s AGLR screen coating which forms a quarter-wavelength filter that cancels reflection rather than diffusing it as other do.Thin BezelsWhen working with multiple monitors, your eyes don’t jump past wide gaps – thus less eye strainEliminates 98.5% screen glare, Compared to a conventional LCD’s 95% glare elimination rate
56 A workstation where all three of these ergonomic features are useful LCD Future TrendsA workstation where all three of these ergonomic features are useful
57 LCD Future Trends LCD Monitor Quality Backlights Zero-Voltage Black The only thing that can wear outThere are more LCDs with 50,000 hour life spansZero-Voltage Blacklessens impact of non-functioning subpixals
58 LCD Future Trends New Technologies On-Glass Circuitry unveiled Oct. 22, 2002The new screens use Sharp’s CGS (continuous grain silicon)Microprocessor circuitry applied directly on the glass, enabling it to function like a computerProduces ultra fine resolutions
59 LCD Future Trends New Technologies (continued) ThinCRTs from Candescent Technologiesquarter-inch thin form factor: a "thin CRT."Thousands of emitters instead of a single large cathode tubeHas the best of both CRTs and LCDs
60 LCD Future TrendsThinCRT from Candescent Technologies
61 Buyer’s Guide To LCD Monitors What to consider when buying a LCD monitorWhat applications are going to be usedHow much room you have on your deskHow much space you need on a virtual desktopHow much you want to spend
62 Buyer’s Guide To LCD Monitors Key features or things to look for when deciding what to buy and how much to spendNative ResolutionLCD uses a matrix of cells to display its image, causing it to have a fixed or native resolution at which the display looks best
63 Buyer’s Guide To LCD Monitors Viewing anglesindicates how you can move to the sides or below the center of the screen before image is being displayedan angle of 160 degrees is recommendedDot Pitchanother indicator of image qualitythe smaller the better; more expensive
64 Buyer’s Guide To LCD Monitors Contrast ratiois the difference in light intensity between the brightest white and the darkest black that an LCD can producehelps determine how rich the color will be in on-screen imagesrecommend a contrast ratio of 300:1 or better
65 Buyer’s Guide To LCD Monitors Digital vs. Analogif you have a graphics card with a digital video-out, choose LCD that has digital inputimage will be clearer because it won’t have to convert from analog to digital and back and forth
66 Buyer’s Guide To LCD Monitors Prices$200 - $500 range: panel size – 15 inches; native resolution – 120/100 to 140/120 degrees; contrast ratio – 200:1 to 300:1$500 - $800: panel size – 15 to 17 inches; native resolution – 120/100 to 140/120 degrees; contrast ratio – 300:1 to 350:1$800 and up: panel size – 17 to 19 inches; native resolution – 150/140 to 170/170 degrees; contrast ratio – 300:1 to 400:1
67 Buyer’s Guide To LCD Monitors Buying TipsStick to 15 inch monitorsbalances screen size and price together wellCheapestLook for a wide viewing anglegood for making presentations and working with partnersindicates a higher quality panel with better brightness and color effectivenessless tendency to leave trails on screen
68 Buyer’s Guide To LCD Monitors Buying TipsTry before you buyactually looking at your desired monitor is always bestdo not buy online or by mail unless the seller has a return policy
69 Buyer’s Guide To LCD Monitors Comparison with CRT buying tipsStick with a 17 inch monitoris big enough and doesn’t take up too much spaceis cheaperif you work with allot of graphics and image editing, go with the $300-$ inch CRT’s
70 Buyer’s Guide To LCD Monitors Comparison with CRT buying tipsNeed to consider power costuses more power than LCD monitorscan find low power CRT monitors that have a TCO’99 sealDo not throw away CRT monitorscontain large amounts of toxins and lead that destroy soil and waterRecycle
71 Buyer’s Guide To LCD Monitors Where To BuyElectronic stores (reasonable prices)Fry’s Electronics, Circuit City, Compaq, Best BuyWebsites – low prices, but can’t see what you are buyingtomshardware.bizrate.comtigerdirect.com
72 Buyer’s Guide To LCD Monitors ConclusionPrices have been falling over the past two yearsmore affordable for consumersKey features and buying tips mentioned should lead consumers in purchasing the right LCD monitor for the lowest price