Electronic Displays ExplainedHitachi Europe Ltd.

CRT Structure

CRT Advantages

Naturally suited to analogue interfaceNative interface is digital (eg. DVI)

Mature technology; cheapMaturing

technology; cost falling

Support multiple resolutions equally wellFixed inherent resolution

Not pixel-based, no problemMissing pixels

Very high (small area) peak brightness possible; gives "sparkle" and "life" to movies/video/photos

Peak brightness limited;

photos look "flat"

Usually portray motion wellMotion-blur

Good black (quality monitor, adjusted)Poor black images

Consistent image irrespective of viewing angle

Contrast/colour change with angle

CRTLCD

LCD Structure (1)

LCD Structure (2)

Commonelectrode

Color Filter

TFT ONOFF

IPS ( In Plane Switching )

Back Light

ONOFF

Color Filter

LiquidCrystal

TFTPolarizer

Electricfield Common

electrode

LiquidCrystal

Polarizer

Pixelelectrode

TN

LCD Advantages

Inherently flicker (although peoples sensitivity varies)

No flicker

Poor text contrast (bandwidth limited)Excellent text contrast

Strong bright areas can cause other regions of the picture to dim

Consistent tonal scale

Tend to suffer from geometric distortions, which may be picture (brightness) dependent, and worsen with age

Perfect image geometry

Limited sharpness; tend to blur more at high brightness, and with age

Perfectly sharp

High power (c.150W)Low power (c.20W)

HeavyLightweight

BulkyCompact

CRTLCD

Colour Reproduction

40%40% 45%45% 50%50% 55%55% 60%60% 65%65% 70%70%28%28%

30%30%

32%32%

34%34%

36%36%

38%38%

40%40%

42%42%

44%44%

Better Display Quality

◇

2001

2002

2003

2004

2006

：Notebook PC：Monitor：TV：Mobile Phone: Automotive

●

●

▲

■

■ ◇

◇

Tra

nsm

ittan

ce

Color saturation

Perfect Viewing from all Directions?

The Normal TFT LCD Reality

IPS TECHNOLOGY ADVANTAGE (1)

Upper 30deg.

Normal TFT

Lower30deg.

Front

IPS

IPS TECHNOLOGY ADVANTAGE (1)

IPS

Normal TFTFront SideLeft Side

GAMMA SHIFT PERFORMANCE

NORMAL TFT

Angle

0

0.2

0.4

0.6

0.8

1

0 100 200

-80

-60

-45

-30

-10

0

10

30

45

60

80

Brightness

Grey Level IPS

0

0.2

0.4

0.6

0.8

1

0 100 200

-80

-60

-45

-30

-10

0

10

30

45

60

80

Grey Level

Brightness

IPS TFT

Angle

Half Contrast AngleDefinition：Viewing angle ranges into half of Contrast Ratio(CR) （°）Measuring Condition：Right and left(H)，Upper and lower(V) （127G/64G:Gray Scale）

IPS

0%

20%

40%

60%

80%

100%

120%

-80 -60 -40 -20 0 20 40 60 80

Viewing Angle (°)

CR

Ｈ

Ｖ

>160°

Normal TFT

Ｈ

Ｖ

59°

0%

20%

40%

60%

80%

100%

120%

CR

-80 -60 -40 -20 0 20 40 60 80

Viewing Angle (°)

LCD Black Level - Horizontal

Brightness is set at 500cd/㎡

Bla

ck L

evel

(cd

/㎡)

Viewing angle (deg)

IPS

Normal TFT

0.0

0.5

1.0

1.5

2.0

2.5

3.0

-50 -40 -30 -20 -10 0 10 20 30 40 50

LCD Black Level - VerticalB

lack

Lev

el (

cd/㎡

)

Viewing angle (deg)

IPS

Normal TFT

Brightness is set at 500cd/㎡

0.0

0.5

1.0

1.5

2.0

2.5

3.0

-50 -40 -30 -20 -10 0 10 20 30 40 50

IPS Display Improvements

(2004～Now)Next GenerationNext Generation

Target(1998～2002) (2002～2004)

Transmittance(a.u.)

新製品

１００

１４００

New Optical design/New alignment

New LCD material/ New driving method

Improved moving picture（10→8ｍｓ）

１８０

Further superiorityFurther superiority

１３０ １５５

３５０ ６３０ ９００Contrast

LCD Performance

IPS Normal TFT

Best point is 10

Transmittance(Brightness or Low Power)

Shift Ratio

0

2

4

6

8

10γ

Front DirectionBlack Level

All DirectionBlack Level

ResponseTime(All gray scale)

(IPS-Pro+Super Impulse)

Color Saturation

Half Contrast Ratio

Motion Picture Color shift&

Color Tracking

The switch from CRT to LCD

(k units)