CAD Output Devices - Gebze Yüksek Teknoloji Enstitüsü

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Nov 16, 2013 (3 years and 4 months ago)

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4.1. CAD
Output

Devices


Dr. Ahmet Zafer Şenalp

e
-
mail:
azsenalp@gyte.edu.tr




Makine Mühendisliği Bölümü

Gebze Yüksek Teknoloji Enstitüsü


ME 521

Computer

Aided

Design

4.1. CAD
Output

Devices



CAD
Output

Devices



Plotter


Printer


CRT
Display



Vector

Display


Storage

Tube


Raster Display


LCD

Display


Plazma Ekranlar


Digital

Light

Processing
-
DLP


OLED


Virtual

Reality


Rapid

Prototyping



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Early pen plotters, e.g., the
Calcomp

565

of 1959, worked by placing the paper over a roller that moved
the paper back and forth for X motion, while the pen moved back and forth on a track for Y motion.

Another approach, e.g.
Computervision
's

Interact I, involved attaching ball
-
point pens to drafting
pantographs

and driving the machines with motors controlled by the computer. This had the
disadvantage of being somewhat slow to move, as well as requiring floor space equal to the size of
the paper, but could double as a
digitizer
. A later change was the addition of an electrically
controlled clamp to hold the pens, which allowed them to be changed, and thus create multi
-
colored output


Hewlett Packard and
Tektronix

produced small, desktop
-
sized flatbed plotters in the late 1960s and
1970s. The pens were mounted on a traveling bar, whereby the y
-
axis was represented by motion
up and down the length of the bar and the x
-
axis was represented by motion of the bar back and
forth across the plotting table. Due to the mass of the bar, these plotters operated relatively slowly



Plotters are mainly used in CAD applications and drafting .


The advantages of using plotters:


High resolution


Usage of large scale paper

Plotter

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Output

Devices





Plotter

Plotter has either vector or raster graphics property and connected to the computer.


Plotter

control languages
:


HPGL, HPGL2 (
Hewlett
-
Packard
)

DMPL

(
Houston Instruments
),

Postscript,
ps
,
eps

(
Adobe
)


Ex
: “
pen

up
=PA”, “
pendown
=PD



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4.1. CAD
Output

Devices





Plotter

Plotters

according

to

structure
:




Flatbed

plotters

D
rum

plotters


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Output

Devices





Plotter


Pen plotters



By moving the pen along the surface of the paper, make drawings.


Limited with 2D drawing commands. Cannot draw raster images. Can draw letters but they are
slow due to the mechanical movement of the pen.

Cannot draw color pictures. They are used for vector graphics.


When the computers were slow they were the fastest drawing devices.


Different
thicknesss

pens or color pens can be used.


Has to change pens in case of using color pens or pens with different thickness.


With the generation of speedy computers, pen plotters disappeared.


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4.1. CAD
Output

Devices






Inkjet plotters


Work with the same principle with inkject printers


Can draw raster pictures.


There are also models avilable that can draw photorealisitic
pictures.


Also used in advertisement sector.



Thermal plotters


They draw on heat sensitive paper or film material by
apllying heat.




Plotter

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Output

Devices






E
lectr
o
static plotters



Draws a raster image to the paper by applying high
voltage. This voltage attracts toner and melts on paper
by the help of heat.


It is fast but more expensive than inkject plotters.



Plotter

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Output

Devices





Character printers:


First printer type that is similar to typewriter. Characters are pressed similar to typewriter. First
samples are in typewriter structure. Later there exists models that type a line at once. This type
of printers are not used widely today due tı complex electromechanical structures, low speeds
and limited printing capabilities.

Printer

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ME 521

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4.1. CAD
Output

Devices





Line

printers
:



A
s the name implies, print an entire line of text at a time
.


Generally

used

with

mainframe

computers
.


Can
print

600
-
1200
line

at a
minute
.


Chain

or

drum

types

are

available
.
In

drum

types

charactes

are

placed

on
the

drum
.

Printer

chain

type

line

printer

Drum

type

line

printers

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4.1. CAD
Output

Devices





Dot
-
matrix

printers

:


In the general sense many printers rely on a
matrix

of
pixels
, or
dots
, that together form the larger
image. However, the term
dot matrix printer

is specifically used for impact printers that use a
matrix of small
pins

to create precise dots. The advantage of dot
-
matrix over other impact printers
is that they can produce
graphical

images in addition to text; however the text is generally of poorer
quality than impact printers that use letterforms (
type
).


Print quality can be poor
-
especially for low
-
density dot
-
matrix printers. The quality of characters
and graphic images often appears to be
ragged

or
unfocused

although some high
-
density dot
-
matrix printers rival those of
letter
-
quality

printers. But, for the most part, dot
-
matrix printers do
not produce high
-
quality text and graphics. Often, dot
-
matrix units are used as
draft

printers. Then,
final outputs of higher quality are prepared on letter
-
quality printers

Printer

Printing

head
:


5x7
type


36x24
type

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Output

Devices





Inkjet Printers:


Ink
-
jet printers

spray tiny drops of ink to form character shapes on paper. Since characters are
formed as a pattern of
dots
, ink
-
jet printers are technically
dot
-
matrix printers.

However the
quality of ink
-
jet output generally is much higher than that of most dot
-
matrix printers

Today inkjet printers have the highest resolution. They are more silent and has small structures
than others.

According to spraying there are piezoelectric and thermal types available.

Printer

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ME 521

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4.1. CAD
Output

Devices





Inkjet Printers:



Thermal inkjet printers


The ink droplet that is heated until nearly 300
°

C in the print head nozzles rooms evaporates and
sprayed to the paper with a small explosion with high speed (100 km/hr).


Due to the need of heating water based inks are used in this type of printing.


Japon

Canon’s inkjet,
Bubblejet

printers work with this principle.


This type of printing is widely used by those who is in need of printing small numbers.



Piezoelectric inkjet printers


In this type of printers, ink spray is made by piezoelectric crystal spray nozzles. Spraying is
done in the form of process
-
induced crystal vibrated spray ink.


In this type as no heating is required, there is no
limitation

in the ink that should be used.


Epson’s printers use this principle. In commercial and industrial applications generally this
kind of inkjet printers are used.

Printer

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ME 521

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4.1. CAD
Output

Devices





Thermal

printers
:



Thermal printers

work by selectively heating regions of special heat
-
sensitive paper.


Monochrome thermal printers are used in cash registers,
ATMs
,
gasoline dispensers

and some
older inexpensive fax machines.


Colours

can be achieved with special papers and different temperatures and heating rates for
different
colours
; these
coloured

sheets are not required in black
-
and
-
white output. One
example is the ZINK technology.


Before

the

invension

of
inkjet

printers
,
thermals

printers

were

used

widely

in CAD
applications
.



Printer

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ME 521

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Output

Devices





Laser printers:


A
laser printer

is a common type of
computer printer

that rapidly
produces high quality text and graphics on
plain paper
. As with digital
photocopiers

and
multifunction printers

(MFPs), laser printers employ a
xerographic

printing process but differ from analog photocopiers in that the
image is produced by the direct scanning of a
laser

beam across the printer's
photoreceptor
.


Latest invented printer type. Silent, high resolution print quality and fast
compared to other printers.
Basically, use a

printing technique

similar

to

photocopy machine.
Main feature that differs in laser printers compared to
photocopy machine
s is that:
numeric codes from the computer is the source
of
printing
.


Signals coming from the computer are drawn on ligth sensitive drum
with the help of laser. This operation enables drawn parts on the drum to be
charged with electricity. These regions are coated with toner. The coated
toner is transfered to the paper. To fix the toner heat is applied between
100
-
150
°
C .


Color types are slo available. Used widely as fast and economical. Laser
printers are also page printers.


Printer

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ME 521

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4.1. CAD
Output

Devices





Cutaway rendering of a color
CRT
:

1.


Three Electron guns (for red,
green, and blue phosphor dots)

2.

Elektron

beams

3.


Focusing

coils

4.


Deflection

coils

5.

Anode

connection

6.


Mask for separating beams for
red, green, and blue part of
displayed image

7.


Phosphor layer with red, green,
and blue zones

8.


Close
-
up of the phosphor
-
coated
inner side of the screen

CRT
Display

CRT :
Chatode

Ray
Tube


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Output

Devices






A cathode ray tube (CRT) is a specialized vacuum tube in which images are produced when
an electron beam strikes a phosphorescent surface. Most desktop computer displays make
use of CRTs. The CRT in a computer display is similar to the "picture tube" in a television
receiver.


A cathode ray tube consists of several basic components. The electron gun generates a
narrow beam of electrons. The anodes accelerate the electrons. Deflecting coils produce
an
extremely low frequency

electromagnetic field that allows for constant adjustment of
the direction of the electron beam. There are two sets of deflecting coils: horizontal and
vertical. The intensity of the beam can be varied. The electron beam produces a tiny,
bright visible spot when it strikes the phosphor
-
coated screen.


To produce an image on the screen, complex signals are applied to the deflecting coils, and
also to the apparatus that controls the intensity of the electron beam. This causes the spot
to race across the screen from right to left, and from top to bottom, in a sequence of
horizontal lines called the raster. As viewed from the front of the CRT, the spot moves in a
pattern similar to the way your eyes move when you read a single
-
column page of text.
But the scanning takes place at such a rapid rate that your eye sees a constant image over
the entire screen.


CRT
Display

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Devices






V
irtually

all CRTs today render color images. These devices have three electron guns, one
for the primary color red, one for the primary color green, and one for the primary color
blue. The CRT thus produces three overlapping images: one in red (R), one in green (G), and
one in blue (B). This is the so
-
called
RGB

color model.


In computer systems, there are several
display modes
, or sets of specifications according to
which the CRT operates. The most common specification for CRT displays is known as SVGA
(Super Video Graphics Array). Notebook computers typically use
liquid crystal display
. The
technology for these displays is much different than that for CRTs.




CRT
Display



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Output

Devices



Every

pixel

on a
display

is
composed

of 3
color

phosphor

droplets
.
The

distance

of
nearest

pixels

is
called


dot

pitch
”.
Today

CRT
monitors

have

dot

pitch

values

between

0.24 mm
and

0.28 mm.
When

this

value

is
smaller

display

quality

is
better
.




A
vector monitor

or
vector display

is a display device used for early computers. It is a type of
CRT
, similar to the
oscilloscope
, but typically uses magnetic, rather than electrostatic,
deflection. Here, the beam traces straight lines between arbitrary points, repeatedly
refreshing the display as quickly as possible.


Vector displays for computers did not noticeably suffer from the display artifacts of
Aliasing

and
pixelation
, but were limited in that they could display only a shape's outline (advanced
vector systems could provide a limited amount of shading), and only a limited amount of
crudely
-
drawn text (the number of shapes and/or textual characters drawn was severely
limited, because the speed of refresh was roughly inversely proportional to how many
vectors needed to be drawn).


Vector displays were used for
head
-
up displays

in fighter aircraft, because of the brighter
displays that can be achieved by moving the electron beam more slowly across the
phosphors
. Brightness is critical in this application because the display must be clearly visible
to the pilot in direct sunlight
.


Vector monitors were also used by some late
-
1970s to mid
-
1980s arcade games such as
Asteroids
.
Atari

used the term
Quadrascan

to describe the technology when used in their
video game arcades
.

Vector

Display

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Devices





Hewlett
-
Packard

made a large
-
screen fast vector monitor, which they called an X
-
Y display. It used
a wide
-
angle electrostatically
-
deflected CRT that was about as compact as a magnetic
-
deflection
CRT. Instead of the deflection plates of a typical CRT, it had a unique structure they called an
electrostatic deflection yoke, with metallized electrodes inside a glass cylinder.

Vector

Display

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Mostly obsolete, a
storage tube

is a special
monochromatic
CRT

whose screen has a kind of 'memory‘
.

W
hen a portion of the screen is illuminated by the CRT's
electron gun
, it stays lit until a screen erase command is
given. Thus, screen update commands need only be sent
once and this allows the use of a slower data connection,
The two main advantages were:


Very low
bandwidth

needs compared to
vector graphics

displays, thus allowing much longer cable distances
between computer and terminal


No need for display
-
local
RAM

(as in modern terminals),
which was prohibitively expensive at the time.

Storage

Tube

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Generally speaking, storage tubes could be divided into
two categories. In the more common category, they were
only capable of storing "
binary
" images; any given point
on the screen was either illuminated or dark. The
Tektronix

Direct
-
View
Bistable

Storage Tube

was perhaps
the most
-
famous example in this category. Other storage
tubes were able to store
greyscale
/
halftoned

images; the
tradeoff was usually a much
-
reduced storage time.


Some pioneering storage tube displays were
MIT

Project
MAC
's ARDS (Advanced Remote Display Station), the
Computek

400 Series Display terminals (a commercial
derivative), which both used a Tektronix type 611 storage
display unit, and Tektronix's
4014

terminal, the latter
becoming a
de facto

computer terminal standard some
time after its introduction (later being emulated by other
systems due to this status).


Storage

Tube

"DVBST"

storage

tube

Tektronix 4014


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Devices






A
liquid crystal display

(
LCD
) is a thin, flat
electronic visual display

that uses the light
modulating properties of
liquid crystals

(LCs). LCs do not emit light directly.


They are used in a wide range of applications including:
computer monitors
,
television
,
instrument panels,
aircraft cockpit displays
,
signage
, etc. They are common in consumer
devices such as video players, gaming devices,
clocks
, watches,
calculators
, and
telephones
.
LCDs have displaced
cathode ray tube
(CRT) displays in most applications. They are usually
more compact, lightweight, portable, less expensive, more reliable, and easier on the eyes.

They are available in a wider range of screen sizes than CRT and plasma displays, and since
they do not use phosphors, they cannot suffer image burn
-
in.


LCDs are more energy efficient and offer safer disposal than CRTs. Its low electrical power
consumption enables it to be used in
battery
-
powered
electronic

equipment. It is an
electronically
-
modulated optical device

made up of any number of
pixels

filled with
liquid
crystals

and arrayed in front of a
light source

(
backlight
) or
reflector

to produce images in
colour

or
monochrome
. The earliest discovery leading to the development of LCD
technology, the discovery of liquid crystals, dates from 1888.
[1]

By 2008, worldwide sales of
televisions with LCD screens had surpassed the sale of CRT units.




LCD

Display



LCD
’s
have

half

life of
approximately

50000
-
7
0
000

hours
.

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Output

Devices





1.
Polarizing filter

film with a vertical axis to polarize
light as it enters.

2.
Glass substrate with
ITO

electrodes
. The shapes of
these electrodes will determine the shapes that will
appear when the LCD is turned ON. Vertical ridges
etched on the surface are smooth.

3.
Twisted nematic liquid crystal.

4.
Glass substrate with common electrode film (ITO)
with horizontal ridges to line up with the horizontal
filter.

5.
Polarizing filter film with a horizontal axis to
block/pass light.

6.
Reflective surface to send light back to viewer. (In a
backlit LCD, this layer is replaced with a light
source.)


LCD

Display

şematik sıvı kristal ekran

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Output

Devices



LCD

Advantages
/
Disadvantages

LCD


Advantages:


Good in stagnant images such as computer display.


Quality products have good brightness.


Because of dimensions require less space.


Has less energy consumption.


Has long life. (Approximately 50000
-

70000 hr)


LCD Disadvantages:



Delay problem. Unnatural view formation when viewing high speed motion.


Black levels: In most of the LCD’s black cannot be displayed properly. Black is
displayed as dark gray.


Viewing
angle
: Perfect display cannot be attained at 170
0

viewing angle.


Less of the LCD’s found in the market have good motion (video) capabilities.


Cheap products use cheap panels which do not cause quality displays.


In poor quality LCD’s dead pixel formation can occur. When dead pixel ratio exceeds
10 % LCD cannot be watch
ed
properly.


In most of the LCD’s unnatural display takes place like digital display.



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Output

Devices





LCD

Display

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Devices






A
plasma display panel

is a type of
flat panel display

common to large
TV

displays
(80

cm/30

in or larger). They are called "plasma" displays because the pixels rely on
plasma

cells, or what are in essence chambers more commonly known as fluorescent lamps. A panel
typically has millions of tiny cells in compartmentalized space between two panels of
glass
.
These compartments, or "bulbs" or "cells", hold a mixture of
noble gases

and a minuscule
amount of mercury. Just as in the fluorescent lamps over an office desk, when the mercury is
vaporized and a voltage is applied across the cell, the gas in the cells form a plasma. (A plasma
is a collection of particles that respond strongly and collectively to electromagnetic fields or
electrical charges, taking the form of gas
-
like clouds or ion beams.) With flow of electricity
(electrons), some of the electrons strike mercury particles as the electrons move through the
plasma, momentarily increasing the energy level of the molecule until the excess energy is
shed. Mercury sheds the energy as
ultraviolet

(UV) photons. The UV photons then strike
phosphor that is painted on the inside of the cell. When the UV photon strikes a phosphor
molecule, it momentarily raises the energy level of an outer orbit electron in the phosphor
molecule, moving the electron from a stable to an unstable state; the electron then sheds the
excess energy as a photon at a lower energy level than UV light; the lower energy photons are
mostly in the infrared range but about 40% are in the visible light range. Thus the input energy
is shed as mostly heat (infrared) but also as visible light.

Plasma

Display

şematik plazma ekran

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Depending on the phosphors used, different colors of visible light can be achieved. Each pixel
in a plasma display is made up of three cells comprising the primary colors of visible light.
Varying the voltage of the signals to the cells thus allows different perceived colors.

Plasma

Display

First

plasma

computer

display
(1981)

şematik plazma ekran

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Plasma

Display

Working

Principle

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Plasma

Display


Advantages
/
Disadvantages

Plasma Display Advantages:


Long life (aproximately 40000
-
60000 hr of half life)


Viewing
angle
: Has 180
0

viewing
angle
.


Plasma’s are 4
-
5 times brillent than CRT’s.



Has very good contrast.



There is no delay or artificial display as in LCD’s.



Colours are verry close to natural colors.


Needs less space.


Plazma Display Disadvantages:



There is no size less than 37 inch.




Dead pixel formation in less quıality products.


Consumes more energy than LCD’s.

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Output

Devices



CRT
-
LCD
-
Plasma


Comparison

CRTs are slightly better than LCDs because:

• cost less.

• displaying more colors.

• reacting faster and displaying moving images without smearing or artifacts.

• using emissive technology (generate their own light) boarder viewing angle
.

LCDs are better than CRTs because:

• smaller and lighter.

• consuming less energy.

• crisper image because each pixel is displayed by a specific set of LCD cells.

• reduced eyestrain and fatigue (no flicker)

• emitting much fewer low
-
frequency electromagnetic emissions than CRTs.

• pivoting in landscape or portrait mode.

• less prone to interference from other devices

• always perfect image geometry

• reflecting less glare than most CRTs.

Plasma vs. LCDs

• Plasma will outperform LCD by providing lots of dark and better contrast,

but LCD outperforms plasma in brightness and color. (larger screen sizes,

burn
-
in)

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Devices



Digital

Light

Processing
-
DLP


A semiconductor
-
based display, from Texas
Instruments (1993)

• A panel of micromirrors are

mounted on tiny hinges
that

enable them to tilt either toward or

away from
the light source in a

DLP™ projection system
(ON/OFF)
-
creating a light or dark

pixel on the
projection surface.

• The white light generated by the

lamp in a DLP™
projection

system passes through a color

wheel as it
travels to the surface

of the DMD panel.

• DLP™ projection system 1
-
chip and 3
-
chip systems

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DLP
Advantages:


Brighter: DLP™ projectors are among the brightest available because DLP™ technology
brings more light from lamp to screen, resulting in more effective presentations
-
even when
ambient light is difficult to control.


Sharper: DLP™ projection's unique reflective technology comes closest to producing the
exact mirror image of an incoming video or graphic signal, resulting in projection that's
seamless at any resolution.


More Reliable: Display systems using DLP™ technology are able to recreate their incoming
source material with each projection, ensuring a full
-
impact projection experience that will
not fade over time.

DLP
Disadvantages:


In some 1
-
chip DLP’s rainbow effect

can be disturbing.


They are not slim as LCD’s and plasma’s.


Lamp life is limited (6000
-
8000 hr).


Lam
p

replacement is expensive (200$
-
500$) .


In 5
-
6 years usage can cost 2 times the cost
ıf

plasma.


Has less viewing angle compared to plasma.

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Invented by Kodak


An
organic light emitting diode

(
OLED
) is a
light
-
emitting diode

(LED) in which the
emissive

electroluminescent

layer is a film of
organic compounds

which emit light in response to an
electric current. This layer of
organic semiconductor

material is situated between two
electrodes. Generally, at least one of these electrodes is transparent.


OLEDs are used in
television

screens,
computer monitors
, small, portable system screens
such as
mobile phones

and
PDAs
, watches, advertising, information and indication. OLEDs
are also used in light sources for general space illumination and in large
-
area light
-
emitting
elements. Due to their comparatively early stage of development, they typically emit less
light per unit area than inorganic solid
-
state based LED point
-
light sources.


An OLED display functions without a
backlight
. Thus, it can display deep
black levels

and can
also be thinner and lighter than established
liquid crystal displays
. Similarly, in low ambient
light conditions such as dark rooms, an OLED screen can achieve a higher
contrast ratio

than
an LCD screen using either
cold cathode fluorescent lamps

or the more recently developed
LED backlight
.


There are two main families of OLEDs: those based upon
small molecules

and those
employing
polymers
. Adding mobile ions to an OLED creates a
Light
-
emitting
Electrochemical Cell

or LEC, which has a slightly different mode of operation.

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OLED displays can use either
passive
-
matrix

or
active
-
matrix

addressing schemes. Active
-
matrix OLEDs (
AMOLED
) require a
thin
-
film transistor

backplane to switch each individual
pixel on or off, and can make higher resolution and larger size displays possible.


Low energy consumtion, thin structure and light weight are the advantages.


By time brithness may decrease.


Also called as "Organic Electroluminescent Device" (OEL).


Generally manufactured on glass but can also be applied to plastics or flexible materials.
Universal Display’s "FOLED“ is an example to the application of flexible materials.


Has high viewing angles.

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Schematic of a bilayer OLED









The emissive and
conductive

layers are made of special organic
molecules

that conduct
electricity
. The
anode

and
cathode

connect the OLED to the
source

of electicity.


When electricity is applied to an OLED, the emissive layer becomes negatively charged and the
conductive layer becomes positively charged.
Electrostatic

forces cause
electrons

to move from the
positive conductive layer toward the negative emissive layer. This causes a change in the electrical levels
and makes
radiation

that has a
frequency

in the range of visible light.


OLED, as with all
diodes
, can only work if
electricity

flows through them in the correct
direction
. The
Anode, connected to the emmisive layer must be at a higher electrical
potential

(more
volts
, more
positive
) than the cathode, connected to the conductive layer, for the OLED to work.


1.
Cathode

(−)

2.
Emissive

Layer

3.
Emission

of
radiation

4.
Conductive

Layer

5.
Anode

(+)

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Advantages


OLEDs can make more different colors at different levels of
brightness

than LEDs. Unlike
LCDs their colors do not change when viewed at an
angle
.


They are also much cheaper to make.


Most LCDs have to have an LED or
Cold Cathode Fluorescent Light
(CCFL) used as a
backlight

to be visible. LCDs also need to use
filters

to work properly. These filters block much of the
light

created by the LED/CCFL. Because of backlighting and filtering, OLEDs use far less
power than LCDs for the amount of light made.


OLEDs also react faster (0.01ms) to changes in
electricity
. They turn on and off much faster
than LCDs (2
-
8 ms).


Can be applied to flexible or various material types.



Disadvantages


LEDs will last longer than OLEDs. This is the biggest problem with OLEDs. Organic materials
have a life limit of 14000 hours (daily 8 hours makes 5 years)


The organic compounds that make up OLEDs are also more easily damaged by
water
.

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Key

Technical

Terms


Refresh Rate of CRTs is refers to how often the screen is redrawn

per second.
With low refresh rates you can get screen flicker and eye

strain. Aim for a rate of
75 Hz for a monitor up to 17 inches in size

and 85 Hz for any larger monitor. LCDs
are basically flicker free so

refresh rates aren't important.




Dot Pitch is the distance in millimeters between phosphors of the

same color.
The smaller the dot pitch, the sharper the image. Opt for

a dot pitch of 0.26 mm or
smaller (usually quote horizontal dot pitch).




Brightness: LCD monitors have several backlights that provide

illumination.
Brightness is measured in units called nits. The majority

of LCDs produce 150
-
200
nits which is fine for most users. The

backlights in a LCD are good for 10 to 50
thousand hours of operation.

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Virtual

Reality

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Virtual

Reality

Stereopsis : Stereopsis is from the Greek word for "solid sight", and thus refers to
perception of three
-
dimensional shape from any source of depth information.


Personal usage


Usage may be disturbing


Narrow viewing angle (like a tunnel)


Maximum resolution:1280x1024



Tracking is possible


Display types:


CRT, LCD, OLED, LCOS,

FLCOS

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