Transcript (F E D) FIELD EMISSION DISPLAY DEEPAK GUPTA EC 3

(F E D)
FIELD EMISSION DISPLAY
DEEPAK GUPTA
EC 3rd YR.
0800131034
PLAN OF
PRESENTATION
WHAT
WHEN
HOW
APPS.
ADV.
CHARACTERISTICS
FED
 FED
is such a display that works a bit
like a cathode-ray tube, except that
electrons are emission procedure
 Instead
of one cathode emission
spraying of electron through number
of hole is done
HISTORY
In 1968, Charles A. "Capp" Spindt at the
Stanford Research Institute had the idea
of fabricating a flat display using
microscopic molybdenum cones singly or
in arrays (FEA’s)
 This development was the enabling
technology the concept for using FEA’s in
a matrix addressed display (FED)

Assembly of FED Device
FED Principles
Field emission displays,
electrons coming from
millions of tiny microtips
pass through gates and
light up pixels on a
screen.
This principle is similar
to that of cathode-ray
tubes in television sets.
The difference: Instead
of just one "gun"
spraying electrons
against the inside of the
screens face, there are
as many as 500 million
of them
.
Cathode
The cathode/back plate is
a matrix of row and
column traces. Each
crossover lays the
foundation for an
addressable
cathode emitters.
Each crossover has up to
4,500 emitters, 150 nm in
diameter. This emitter
density assures a high
quality image through
manufacturing
redundancy, and long-life
through low operational
stress.
Emission
Emitters generate
electrons when a
small voltage is
applied to both row
(base layer) and
column (top layer).
FED PACKAGING
 The
field emission display screens are
comprised of a thin sandwich. In this
the back is a sheet of glass or silicon
that contains millions of tiny field
emitters which is the cathode. The
front is a sheet of glass coated with
phosphor dots, which is the anode.
FED CHARACTERISTICS
 Comparing
with the CRT displays the
field emission displays has many
advantages.
 They are:
1. Brightness
2. Speed
3. Compact and lightweight
4. Display size
5. Low driving voltage
6. Wider viewing angle
7. High illumination
8. Colour Quality
FED advantages
Inherently high luminous efficiency
 No Response Time issues
 CRT-like Colour Gamut
 Lower Power Consumption



Flat Panel Technology



Cold Cathode Emission
Distance between cathode and screen
~0.2–5mm
Matrix Addressed – No DY
Capital investment for
manufacturing VLS TV with
printable CNT FEDs - 1/10th of LCD
Cost advantage over LCD could be
40%
Technology
CRT (at
30KV)
Luminous
Efficiency
(Lm/W)
3
PDP
0.8
LCD
3
OLED / PLED
5
FED at 8 KV
7
APPLICATION
This technology could produce
affordable large displays in the 20
to 40-inch diagonal range suitable
for TVs.
DRAWBACKS
a. Vacuum tubes do require maintenance.
b. Current FEDs often suffer from variation in
screen brightness across the display, and also
within each pixel.
c. Durability due to electrical discharge in the small
gaps everywhere in FED prototypes.
d. The killing problem was durability: the tips could
not survive under severe conditions of arcing
(i.e. electrical discharge) due to the small gaps
everywhere in FED prototypes.
Thank you ...