1. Plasma Display Panel Principle
What is Plasma
Basic Pixel Drive
Picture Reproduction
Panel Structure
Weakness of PDP
Plasma Display Panel(PDP) Principle
Will explain the principle of Panasonic Plasma display as
1. What is Plasma？
2. Pixel Drive System
３. Picture reproduction
４. Panel Structure
5. Problem of PDP
CLICK

2. What is Plasma 1. What is Plasma 2. How to use Plasma CLICK
Will tell you meaning of Plasma and common usage of plasma technology for our life.
So that you can understand what is plasma.
CLICK
CLICK

3. What is Plasma Solid Liquid Gas Plasma Atom Atom CLICK + + - + - + + -
Low
Temperature
High
Solid
Liquid
Gas
Plasma +
+ -
+ - +
+ - +
- +
It is well known that all objects on the earth are consist of solid, liquid or gas.
However there is one more condition which is called Plasma.
Plasma is that Atom is ionized to Ion and Electron.
CLICK
all most of things in the universe are Plasma state. +
+ -
- +
+ Ion
- Electron
Atom
Atom
CLICK

4. Plasma - UV - - + Temperature or Voltage potential CLICK
When some energy pressure like high temperature or high voltage is applied to atom. The energy increased higher than certain level,
CLICK
Electron leave from Ion.(This is called discharge)
Energy pressure is continuously applied ionization state is kept.
This is called Plasma.
Plasma generate Ultra Violet Lay.
Plasma also generate some other radiation such as Infrared Ray, different frequencies Electro-magnetic.
Temperature or
Voltage potential
CLICK

5. Discharge . ~ Fluorescence lamp Start Discharge Discharge
Low Pressure Gas . UV ~
Visible Light
Start Discharge
Plasma is used for our house or office light as Fluorescence lamp.
Fluorescence lamp is the glass tube which low pressure gas is sealed with two electrodes.
CLICK
Some voltage is supplied between two electrodes discharge start. Gas is ionized and Ultra violet lay (UV) is generated.
UV hits the fluorescence substance and visible light is emitted.
However to start discharge higher voltage is required( start voltage or Pilot voltage). After discharge start supply voltage can decline to keep discharge .
Discharge
Start Voltage
Voltage
Normal Glow
Current
CLICK
CLICK

6. Basic Pixel Drive 1. Pixel Structure 2. Drive Process CLICK
Move to Basic plasma display pixel structure.
CLICK
CLICK

7. Pixel Structure Rib Rib Colour Phosphor Scan Electrode Data Electrode
Xenon +
Neon
Sustain Electrode
Approximately 1.2 millions pixels (852 x 3{3 colours} x 480) are formed between rear and front glasses plate.
2 glass plate have 3mm depth.
CLICK
3 electrodes is located on glass plates, Data electrode is on rear glass and scan and sustain electrodes are on front glass.
Scan and Sustain electrodes are made by transparent material.
Each colour`s area are divided by the Ribs.
Dielectrics are painted on rear and front glasses.(Overcoat (MgO) is also applied on the front glass)
Colour phosphor is applied .
Low pressure(Approx Torr) of Xenon and Neon gas is applied into the pixels and sealed.
IR(Infrared Lay) / EMI(Electro-Magnetic interference) filter glass is applied in front of front glass.
Dielectrics
Aluminum
Base
Rib
Rear Glass
Front Glass
CLICK
CLICK
CLICK
CLICK
CLICK
CLICK

8. Clear the Electric charge
Initialization
Clear the Electric charge =
Pixel can not be controlled if the electric charge is remained.
Therefore at first all remained charges are cleared by Initialization.
CLICK
CLICK

9. Initialization +++ +++ Vs CLICK CLICK | | | | | |
| | |
| | | Vs
+++
+++
To remove(Initialize) Electric charge(wall voltage), sharp edge pulse is applied to sustain electrode and make discharge short period.
Then any electric charge(wall voltage) is initialized.
CLICK
From 2nd sub field this function initialize remaining wall Voltage.
CLICK
CLICK

10. = Write (Address) Select the emission required Pixel CLICK
2nd function is Write(address) which select the emission required pixel.
CLICK
CLICK

11. Drive Write +++++ +++++ Ionization + Ions - Electrons CLICK CLICK
Discharge
Ionization
+++++
| | | | |
+++++
| | | | |
Data Pulse
Scan Pulse
CLICK
Data Pulse which is positive polarity is input to data electrode and Scan pulse which is negative polarity is input to scan electrode simultaneously.
That means sum of data and scan pulses voltage is applied between two electrodes as discharge start voltage.
Discharge is started into the pixel and gas is ionized.
+ Ions
- Electrons
CLICK
CLICK

12. Wall Voltage ++++ +++++ Vw CLICK CLICK | | | | | | | | |
| | | | |
++++
+++++
| | | | Vw
After input pulses gone, Ions and Electrons which is generated by discharge are charged on the dielectric around the electrodes.
This charge is called Wall Voltage (Pilot voltage).
This operation is called Write which data “1” is memorized into a pixel.
CLICK
CLICK
CLICK

13. Sustain
Emit the visible light =
Move to sustain function.
CLICK
CLICK

14. Sustain Step 1 ++++ +++ Vs Vs + Vw CLICK CLICK | | | | | | | CLICK
| | | |
| | |
CLICK
Negative polarity’s Sustain pulse is input between sustain and scan electrodes and voltage potential between two electrodes becomes sum of Sustain pulse and wall voltage.
Then discharge start again.
(However if wall voltage is not charged on the pixel discharge can not start even sustain pulse is supplied.)
CLICK
CLICK

15. Sustain Step 2 +++ +++ Vs CLICK | | | | | | CLICK
| | |
+++ Vs
+++
| | |
CLICK
Ions and Electrons which is generated by 1st sustain discharge are charged on the pixel wall(dielectric) around the electrodes.
CLICK

16. Sustain Step 3 +++ Vw CLICK | | |
| | | Vw
+++
This electric charge will be next discharge`s wall voltage.
Polarity of 2nd charge is reversed from initialization wall voltage.
CLICK
CLICK

17. Sustain Step 4 +++ +++ Vs Vs + Vw CLICK | | | | | | CLICK
| | |
| | |
Vs + Vw Vs
+++
+++
CLICK
Positive polarity’s Sustain pulse is input between sustain and scan electrodes and discharge start again.
CLICK

18. Sustain Step 5 +++ +++ Vs CLICK | | | | | | CLICK
| | | Vs
| | |
+++
CLICK
Ions and Electrons which is generated by 2nd sustain discharge are charged on the pixel wall(dielectric) around the electrodes.
CLICK

19. AC Drive Type Plasma Display
Sustain Cycle
Repeat Step 1 to Step 5
Sustain Pulse
To keep discharge continuously step 1 to 5 operation will be repeated.
As this result sustain pulse is alternated. Therefore we call this drive system AC Drive type.
(There is one other system called DC drive system which sustain voltage is supplied only one direction.)
CLICK
AC Drive Type Plasma Display
CLICK

20. Light Emission UV UV CLICK
Ultra Violet lays are generated By the sustain operation and they are converted to visible lights by Colour phosphor.
Level of visible light will be increased by sustain discharge time.
CLICK UV
CLICK

21. Sub Field Initialize Sustain
Write
Sustain
Address
Period
Sustain
Period
Initialize, Write and sustain function’s cycle is called Sub-Field.
Initialize and Write period are specially called Address period.
Sub-Field cycle is Key of PDP picture reproduction operation.
CLICK
Sub Field
CLICK

22. Picture Reproduction 1. Comparison 2. Scan 3. Emission
4. Brightness control (Sub-Field Drive)
Move to next section.
We explain how to reproduce the picture on PDP through following 4 points.
1. CRT comparison
2. Scan method
3. Emission method
4. Brightness control method
CLICK
CLICK

23. PDP vs CRT CRT PDP Interlace Progressive
Scan Dot Sequence Line Sequence
Interlace Progressive
Emission Dot Sequence Simultaneous
Phosphor Electron Ultra Violet Lay
Excitation
Brightness Beam Current Discharge Time
Control (Sub-Filed Drive)
Scanning, Emission, Colour phosphor, and brightness control method of PDP and CRT is completely different .
Will explain one by one.
CLICK
CLICK

24. Line Sequence Scan Line Sequence Dot Sequence Y1 Y1 Y2 Y2 Y3 Y3 Y4 Y4
CRT use Dot sequence scanning system which address (select) emission point in order. (from left to right and move to next lower line.)
PDP use Line sequence scanning which address one line’s emission points simultaneously and move to next lower line.
CLICK
Line Sequence
(PDP/LCD)
Dot Sequence
(CRT)
CLICK

25. Progressive Scan Interlace Progressive (CRT) (PDP) CLICK CLICK
Please see interlace and progressive scanning difference.
CLICK
Interlace scanning is used for conventional CRT TV`s.
To display one picture scanning is carried out twice because picture(Frame) is divided to 2 section(Field).
Progressive scanning is used for PDP, Flicker free TV, LCD and High-definition TV.
To display one picture scanning is carried out once.
Interlace
(CRT)
Progressive
(PDP)
CLICK
CLICK

26. Emission Dot Sequence Simultaneous Emission Emission (CRT) (PDP) CLICK
One of biggest difference between CRT and PDP is that Scanning and emission of CRT are carried out simultaneously
but PDP’s scanning and emission are done separately.
Please see the difference.
CLICK
However all pixels on PDP screen are emitted at the same time after the address(scanning).
Dot Sequence
Emission
(CRT)
Simultaneous
Emission
(PDP)
CLICK
CLICK

27. Sub Field Drive System =
1 TV Field =
8 Sub Fields
1st 2nd 3rd th th th th th
Sub-Field drive is PDP unique system.
One pixel’s brightness level for one picture(one Field) is reproduced by 8 times Sub-Field operations.
Each Sub-Field’s address period are all same.(This means address operations are same.)
But Sustain period of each Sub-Field are different.
1st Sub-Field(SF) reproduce only 1 step of brightness.
2nd SF reproduce 2 step of brightness.
Each SF ‘s sustain period are increased in order to binary code counting.
So that sustain period increase as 1, 2, 4, 8, 16, 32, 64, 128.
As the result total 256 brightness difference can be displayed on the screen.
This method is called Sub-Field Drive system.
CLICK
Address Period
CLICK

28. Sub Field Drive 8 Sub Fields Vertical Scan CLICK CLICK CLICK Time
7th Sub-field
8th Sub-field
Initialize
Vertical Scan
During the address period Initialization and vertical scan is carried out .
Then brightness of each pixels is increased during sustain period.
CLICK
For example 7th and 8th sub-Field’s initialization, scanning and sustain are done like this.
Vertical Scan = Write
Sustain
CLICK
CLICK
CLICK

29. // // // // Y1 // Y2 Y3 // // Y480 Vertical Scan Vertical Scan
R Data //
G Data //
B Data // Y1 // Y2 Y3 //
This shows the relation of each colours data pulse and scan pulse.
CLICK
For example
Y1 lines scan pulse and R and B data pulses are matched. Then Y1-Red and Y1-Blue pixels are addressed (Means wall voltage is charged.)
But G data is “0”. Then Y1-Green pixel has no-wall voltage.
CLICK 3 times
This function is carried out for all lines.
Vertical Scan
Initialization //
Y480
CLICK
CLICK 3 times
CLICK
1 Sub Field

30. Brightness Control 1 1 1 1 1 1 1 1 : : : : : : : : 0 1 1 1 1 1 1 0
Analogue Video Signal
8 Bit Digital Video Signal
1st Line
: : : : : : : :
120th Line
: : : : : : : :
Video signal data for Sub Field Drive System is re-arranged like this.
Analogue video signal is converted to 8 bits digital data.
CLICK
Each line’s 8 bits digital signals are re-arranged bit by bit.
And LSB(Less significant bit) data is applied to 1st sub field.
2nd bit data is applied 2nd sub field
MSB(Most significant bit) data is applied to 8th sub field.
( 8 bits serial data is converted to 240 bits serial data )
240th Line
7th S.F.
1st Sub Field
4th S.F.
2nd S.F.
5th S.F.
8th S.F.
Sampling point
3rd S.F.
6th S.F.
Sub Field Drive System
CLICK
CLICK

31. Brightness Control 8 Sub Fields t Pixels CLICK Very Bright Bright Dark
Very Bright
Bright
8 bits data select(Address) which sub-Field will be used for sustain or not.(Write)
Then selected sub-field are sustained the discharge.
As the result sum of sustain time set the brightness level of pixel.
Very bright picture’s pixel is set to 256 steps brightness level.
Bright picture’s pixel is set to 137 steps brightness level.
Dark picture’s pixel is set to 23 steps brightness level..
Very dark picture’s pixel is set to 2 steps brightness level.
CLICK
Dark
Very Dark t
Pixels
CLICK

32. Brightness Control Pixel 8 Sub Fields Data Data CLICK CLICK
Show you simulation of how to change the brightness level depend on sustain time difference.
CLICK
Hope you can understand the brightness control method by sub filed drive system.
Data
CLICK
CLICK

33. Panel Structure CLICK CLICK CLICK CLICK CLICK CLICK
Move to AC drive type PD panel structure section.CLICK
At first Data electrodes are mounted on the Rear glass.CLICK
Dielectrics is coated on the Rear glass.CLICK
Ribs are formed as colour area divider.CLICK
Colour phosphors are formed .CLICK
Scan and Sustain transparent electrodes are mounted on the front glass.CLICK
Dielectrics is coated on the front glass.CLICK
MgO overcoat is applied on the front glass.CLICK
From this basic structure Re, Green and Blue colour are reproduced.CLICK
CLICK
CLICK
CLICK
CLICK
CLICK
CLICK

34. Weakness of PDP 1. Black Reproduction 2. Motion Picture Disturbance
3. After Image (Burning)
4. High Panel Current
5. Transportation damage
6. Barometric Pressure
Next we will explain weakness of PDP.
To reproduce moving picture by PDP we found some of PDP unique problem.
First one is Black reproduction .
Second is Motion Picture Disturbance(False noise and colour)
Third is After Image.
Fourth is that PDP needs high Power consumption.
CLICK
CLICK

35. Side effect of Sub-Field Drive Initialization Discharge
1. Black Reproduction
CRT`s Black
PDP`s Black
0 Beam
0 Sustain
Reason
Side effect of Sub-Field Drive
In case of CRT display, if beam current is “0” screen has no emission.
But PDP’s black picture has small emission.
CLICK
PDP need initialization discharge at each Sub-Field even signal data is all ”0”. That means 8 times discharge is occurred at each field.
This is side effect of Sub-Field Drive system.
Initialization Discharge
CLICK
CLICK

36. 1. Pixels Emission Timing Difference due to Sub-Field Drive System
2. Motion Picture Disturbance
Reason
1. Pixels Emission Timing Difference
due to Sub-Field Drive System
2. Human Eyes Visual Sense Speed
Next
W can see strange phenomenon on moving picture. We call this Motion Picture Disturbance(MPD).
Reason of this problem is relation of pixels emission timing difference and Human eyes visual sense.
This is caused by Sub-Field Drive System.
CLICK
CLICK

37. 1) Object move to right False Noise & Colour CLICK 4 times CLICK
Show you simulation of this phenomenon.
When a person is displayed on the left side of the screen.
Then if he move to right side of screen ,
CLICK 4 times with picture change.
Black noise appear side edge of him.
Also red line appear on his cheek.
To repeat demonstration Press “ P “ key 4 times.
And CLICK 4 times again.
False Noise & Colour
CLICK 4 times
CLICK

38. 2) Object move to Left False Noise & Colour CLICK 4 times CLICK
When a person is displayed on the right side of the screen.
Then if he move to left side of screen ,
CLICK 4 times with picture change.
white noise appear side edge of him.
Also green line appear on his cheek.
To repeat this Press “ P “ key 4 times.
And CLICK 4 times again.
False Noise & Colour
CLICK 4 times
CLICK

39. Pixels Discharge time Discharge off CLICK CLICK 1 2 4 8 16 32 64 128
127
This phenomenon is caused by Sub-Field drive system.
For example
If there is white pattern signal but it has 128 steps (50% APL) and 127steps(49%APL) white level area.
CLICK
If these slight level different area sift to right, black noise can be seen.
Because the emission timing of 127 steps area and 128 steps area is not matched.
127 steps area use from 1st to 7th sub-field .
128 steps area use only 8th sub-field.
127
Discharge time
Discharge off
CLICK
CLICK

40. Dynamic False Noise (Contour)
127
128
127
128
128
127
127
128
128
Pixels
127
127
127
127
127
1st Field
128
128
128
128
128
127
127
127
127
127
2nd Field
128
128
128
128
128
127
127
127
127
127
3rd Field
On the still picture, pixel is repeated emission and blanking.
CLICK
However when picture move to right side blanking is done for twice at the edge part.
Long blanking period can be seen as black noise called false noise.
If picture move to right to left white false noise can be seen.
128
128
128
128
128
127
127
127
127
127
4th Field
Time
128
128
128
128
128
127
127
127
127
127
5th Field
128
128
128
128
128
CLICK
CLICK

41. < Still Picture > < Moving Picture >
False Colour
Magenta
Picture
This phenomenon occur also some of neutral colour.
CLICK
Blue level is slight different magenta is moved
Red pixels emission timing will not change but blue pixel emission timing will change.
During blue blanking of the edge part only red pixel is emitted.
This can be seen red line(noise) for human eyes. + + +
CLICK
CLICK
< Still Picture >
< Moving Picture >

42. Panasonic PDP PDP Welcome to Japan
3. After Image (Burning)
Panasonic
PDP
PDP
Welcome to
Japan
If still picture is displayed long time,
CLICK
this picture image leave on the screen.
This is called after Image.
After image level is depend on still picture display time and picture level.
Most case, after image can eliminate by normal picture display (Moving picture or white pattern)
However it is possible to have permanent burn depend on display time .
If Colour phosphor receive Ultra Violet ray continuously emission efficiency will decrease.
CLICK

43. Temporary burn Permanent burn
After Image (Burning)
Reason
Gas is activated (Easy to discharge)
If high white levels signal is displayed emission level of this area’s pixels increased. Because gas is activated. Then activated gas generate more Ultra Violet lay than normal gas.
Therefore activated gas area become brighter than normal gas area.
CLICK
Temporary burn
Permanent burn
CLICK
CLICK

44. = + Matsushita Reason Plasma Display is Large Capacitor
4. High Power Consumption
Reason
Plasma Display is Large Capacitor
Next
One of the biggest problem of PDP is high power consumption of panel.
Because panel is large capacitor and this big element is driven by high frequency sustain pulse.
CLICK = +
Matsushita
CLICK

45. Stray Capacitor CS (Stray Capacitor) Scan Electrode Sustain Electrode
Specially between scan and sustain electrodes unnecessary capacitor component called” Stray Capacitor” is formed .
CLICK
Sustain Electrode
CLICK

46. Stray Capacitor Cs x 852 x 480 x 3 = Cs x 1.23 million (F)
Sustain Voltage
Stray capacitor (Cs) on each pixel is very small. ( ?? uF)
However total stray capacitors on the screen is Cs multiplied by number of pixels . (480 x 852 x 3 = )
Each pixel’s Sustain current is very small but total sustain current become very large.
CLICK
Sustain Current
CLICK

47. N.G. UPRIGHT only No Lie Down 5. Transportation Damage
Transportation and Handling Condition
Plasma Display
Plasma Display
N.G.
Barometric pressure of most residence area in the world is 1 Torr or near. And gas pressure for 42 inch PDP.
Therefore front glass always has external pressure and is upheld by Ribs.
CLICK
1 Torr = Pa
UPRIGHT only
No Lie Down
CLICK
CLICK
CLICK

48. Enough Strengthen Upright Transportation Vibration / Shock CLICK CLICK
Barometric pressure of most residence area in the world is 1 Torr or near. And gas pressure for 42 inch PDP.
Therefore front glass always has external pressure and is upheld by Ribs.
CLICK
1 Torr = Pa
CLICK
CLICK

49. = Transportation Damage Rib Crack by Transportation vibration
Defect pixel
Barometric pressure of most residence area in the world is 1 Torr or near. And gas pressure for 42 inch PDP.
Therefore front glass always has external pressure and is upheld by Ribs.
CLICK
1 Torr = Pa
CLICK
CLICK

50. Barometric Pressure Barometric Pressure Gas pressure CLICK CLICK CLICK
Next
Lower pressure gas is sealed in the PDP panel.
CLICK
Therefore front glass always has barometric pressure on the its surface.
Show the panel in section.
Barometric Pressure
CLICK
CLICK
CLICK
CLICK

51. Barometric pressure / 1 Torr
Sea level area
Barometric pressure / 1 Torr
Barometric pressure of most residence area in the world is 1 Torr or near. And gas pressure for 42 inch PDP.
Therefore front glass always has external pressure and is upheld by Ribs.
CLICK
1 Torr = Pa
Gas pressure / 0.6 Torr
CLICK
CLICK
CLICK

52. pressure / 1 Torr Over 3000 meters above sea level
Pressure / below 0.6 Torr
pressure / 1 Torr
Gas Pressure / 0.6 Torr
However some city or town located over 3000 meters mountain have lower barometric pressure.
CLICK
If pressure become below 0.6 Torr front glass will have internal pressure by sealed gas.
In this case, front glass is bent and discharge may not start specially centre area of screen.
CLICK
CLICK
CLICK

53. END of PDP Principle presentation
To improve PDP picture quality specially brightness we have to solve many problems.
CLICK