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Bahirdar University Bahirdar institute of technology
Faculty of computing
Department of computer science
Tesfahunegn Minwuyelet
1
Table of Contents1 Cathode Ray Tube (CRT) Displays........................................................................................................1
2 Liquid Crystal Display (LCD).................................................................................................................2
3 Plasma Display Panels..........................................................................................................................2
4 Light-emitting diode (LED) Displays.....................................................................................................3
5 Organic Light-emitting diode (OLED) Displays.....................................................................................4
6 LED-backlight LCD................................................................................................................................5
i
Prepare summary sheet that shows comparison of display devices listed below based on the following comparison criteria:-
a. Maximum possible screen size
b. Screen slimness
c. Brightness
d. Resolution
e. Contrast ratio
f. Power consumption
g. Price
h. Viewing Angle
i. Lifetime
j. Usage
1 Cathode Ray Tube (CRT) Displaysa. Maximum size for direct-view displays is limited to about 40 inches due to
practical and manufacturing restrictions
b. They have a big back and take up space on desk (i.e. they are heavy to pick up
and carry around).
c. It can easily increase the monitor’s brightness by reflecting the light.
d. Higher resolution.
e. The contrast features of the cathode ray tube monitor are considered highly
excellent (i.e. High contrast ratio (over 15,000:1)).
f. Higher power consumption.
g. Lower cost (i.e.The Cathode Ray Tube monitors have lower price rate than the
LCD display or Plasma display).
h. Excellent viewing angle.
i. Long life (a few or several decades, depending on use).
j. CRT are less fit to be installed in outdoor locations, although many were. Even
though CRTs are still popular in the printing and broadcasting industries as well
as in the professional video, photography, and graphics fields due to their greater
color fidelity, contrast and better viewing from off-axis (wider viewing angle).
CRTs also still find adherents in video gaming because of their higher resolution
per initial cost, fast response time, and multiple native resolutions.
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2 Liquid Crystal Display (LCD)a) Take up about 40% less desk space. LCDs are thin and compact.
b) It is a thin, flat panel used for electronically displaying information such as text,
images, and moving pictures (i.e. completely flat screen).
c) Produces very bright images due to high peak intensity. Very suitable for
environments that are brightly lit.
d) Works best at the native resolution. The native resolution cannot be changed. All
other resolutions require adjusting procedures which can cause considerable
deterioration of the image.
e) The aspect ratio and resolution are fixed (i.e. Lower contrast than CRTs due to a
poor black-level.)
f) Energy efficient. Consume less than 1/3 the power of a comparable CRT.
Consume less electricity than a CRT and produce little heat.
g) Considerably more expensive purchase price than comparable CRTs.(Cheaper
lifetime cost: lasts about 13,000 - 15,000 more hours than a typical CRT).
h) Longer life:-LCDs have a longer useful life than CRTs.
i) Restricted viewing angles. Viewing angles affect the brightness, contrast and
colours shown. Wide angles can lead to contrast and colour reversal.
j) Its uses include computer monitors, televisions, instrument panels, and devices
ranging from aircraft cockpit displays, to every-day consumer devices such as
clocks, calculators, and telephones.
3 Plasma Display Panelsa. Common to large TV displays 30 inches (76 cm) or larger. They can be
produced in fairly large sizes up to 3.8 meters (150 in) diagonally.
b. It is a type of flat panel display(i.e. Plasma displays are thinner than
cathode ray tube (CRT) displays)
c. Brighter than liquid crystal displays (i.e. Plasma displays are bright
(1,000 lux or higher for the module).
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d. Plasma TVs scale the video image of each incoming signal to the native
resolution of the display panel.
i. ED Resolutions1. 840×4802. 853×480
ii. HD Resolutions1. 1024×1024 (discontinued)2. 1024×7683. 1280×7684. 1366×7685. 1280×10806. 1920×1080
e. Has good contrast ratio.
f. Use more electrical power, on average, than an LCD TV. Power
consumption is 400 watts for a 127 cm (50 in) screen, 200 to 310 watts for
a 127 cm (50 in) display when set to cinema mode and Most screens are
set to "shop" mode by default, which draws at least twice the power
(around 500–700 watts) of a "home" setting of less extreme brightness.
g. Considerably more expensive purchase price than comparable CRTs
h. Wider viewing angles than those of LCD; images do not suffer from
degradation at high angles like LCDs
i. Long life time
j. It may cause a buzzing noise. For those who wish to listen to AM radio, or
are amateur radio operators (hams) or shortwave listeners (SWL), the
radio frequency interference (RFI) from these devices can be irritating or
disabling. Does not work well at high altitudes above 2 km due to pressure
differential between the gases inside the screen and the air pressure at
altitude.
4 Light-emitting diode (LED) Displaysa) Screen size: Up to 90 inches LEDs can be very small (smaller than 2 mm2) and
are easily populated to circuit board.
b) It is a flat panel display
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c) Has improved brightness.
d) Its contrast ratio is similar to plasma display.
e) Long life time
f) Command a price 20 percent above that of LCD featuring and identical screen
size and specification.
g) Life span : Around 100,000 hours
h) Viewing Angle : The brightness and color on LCD TVs shift noticeably over the
screen and depending on viewing angle
i) Power saving advantage make them attractive prospective for long term use.
j) It can be used as Flash an LED of type (Single LED and Multiple LEDs).and for
Traffic Light by use of LEDs
5 Organic Light-emitting diode (OLED) Displays a) Has max size. Can be made to larger sizes.
b) Thinner, lighter and more flexible.
c) Better impression for higher brightness
d) High resolution, <5μm pixel size.
e) High contrast ratio of 10,000: 1.
f) Consume significantly less energy.
g) Expensive. But sometimes has low cost materials and fabrication method (i.e.
Less Expensive than LCD due to lesser components).
h) Higher viewing angle up to 170 for constant contrast ratio.
i) Lifetime - While red and green OLED films have longer lifetimes (46,000 to
230,000 hours), blue organics currently have much shorter lifetimes (up to around
14,000 hours).
j) Organic Light Emitting Diodes are evolving as the next generation displays
OLED TV, Mobile phones with OLED screens and Roll top Laptop.
6 LED-backlight LCDa) Broad range of screen size.
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b) It is a flat panel display. Can be extremely slim (some screens are less than 0.5
inch (0.92 cm)) thin in edge-lit panels
c) Has good brightness.
d) Heightened contrast.
e) Has high resolution.
f) High native contrast ratio.
g) Consume significantly less energy.
h) with very good viewing angles
i) LED-backlit LCDs have longer life than plasma and CCFL LCD TVs
j) The iPhone 5 has an LED-backlit TFT IPS LCD, while the Sony Xperia S is an
example of an LED-backlit TFT TN LCD (also referred as TFT LCD).
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