“Plasma display panels: physics, recent developments and key issues”

Presentation on theme: "“Plasma display panels: physics, recent developments and key issues”"— Presentation transcript:

1 “Plasma display panels: physics, recent developments and key issues”
Kim, Kang Hwi Department of Electrical Engineering Seoul National University

2 What is the ‘PDP’? Gorgeous TV ?? Plasma : 플라즈마 현상 이용
Display : 문자 및 영상 표시 Panel : 플라즈마 생성환경 조성 및 픽셀 형성

3 PDP의 역사적 발전 1950년대 초, Saul Kuchinsky와 그의 동료들에 의해 DC PDP가 개발
1964년, 미국 일리노이 대학의 Bitzer와 Slottow 교수가 AC PDP 구조를 고안 1979년, Fujitsu사의 Shinoda 박사가 형광 발광 AC PDP를 최초로 구현 1984년, Shinoda 박사가 3전극 면방전 구조를 채용한 컬러 AC PDP를 고안 1990년대 중반부터 활발한 성능개선, 한국이 주도!!

4 PDP의 특징 Size Space View Angle Full Color Resol-ution Bright-ness
Cont-rast Power PDP ★ ○ △ CRT X LCD Projector

5 AC PDP의 Structure

6 Plasma 물질의 상태 변화

7 AC 방전 원리 (1) Wall Charge Glow discharge

8 AC 방전 원리 (2) 진공자외선의 발생 Gas Mixture (Xe and Ne)
Xe Exitation and UV emission Resonant emission : wavelength 147nm Molecular emission : wavelength 173nm 형광체에 의한 가시광선 발생 Host Lattice and Activators → Energy transition efficiency → 열화현상에 의한 가시광선 효율저하

9 기본 구조 FRONT PLATE GLASS REAR PLATE GLASS DIELECTRIC LAYER
ADDRESS PROTECTIVE LAYER MgO LAYER (전자방출) DIELECTRIC RIB DISPLAY ELECTRODE ADDRESS ELECTRODE PHOSPHORS First plasma display Prof. Bitzer at UIUC Fall Joint Computer Conference, 1966 Drawing from US Patent

10 세부 구조와 특징 3극 구조 : 어드레스(A), 유지(X), 스캔(Y) 전극 면 방전 : 유지 <-> 스캔 전극
가스 방전시 자외선 발생  형광물질을 자극하여 가시광선 방출 (수 백만개의 작은 형광등 = PDP)  자체 발광 (LCD와의 차이) AC Matrix AC Coplanar 투명한 전면판을 통하여 빛 방출 기억 효과 (memory effect)  남아있는 벽 전하가 벽 전위(Vw)를 형성 (벽 전하가 있는 경우에 on, 그렇지 않으면 off) +(-) V –(+)

11 패널 구동 ADS (Address Display Separated) 구동 방식 RESET ADDRESS SUSTAIN
Addressing line by line Sustaining all line simultaneously 256 gray level (8-digit) * 계조 (gray level) 표현 : 시분할 방식

12 Expression of Image in PDP

13 Current Issue Efficiency : 2 lm/W  5 lm/W Image Quality Lifetime
Discharging mode Electrode shape Cell geometry Gas mixture Material (phosphors, reflection layer) Addressing and sustaining scheme Image Quality Color depth Contrast ratio False contour Low gray-level Lifetime Erosion of transparent dielectric protection layer Degradation of phosphor’s quantum efficiency

14 Efficiency Other research : only 0.56% from electric input power
from J. Phys. D: Appl. Phys. 36 (2003) p.64 not including loss in electric drivers Other research : only 0.56% from electric input power from “PDP engineering”, 2007

15 Enhancing Efficiency ALiS (Alternate Lighting of Surfaces)
from Fujitsu Sci. Tech. J., 35 (1999), p.237

16 Enhancing Efficiency T-shaped electrode + WAFFLE rib
DelTA cell structure

17 Enhancing Contrast Ramp reset
proposed by Weber (UIUC) US Patent (1998) Ramp-biased Multiple Short Pulse (RMSP) reset proposed by Jin Ho Yang (SNU), IEEE Transaction on Plasma Science (2004)

18 Enhancing Performance
Characteristics on ADS (Address Display Separated) scheme Pros Wide operation voltage margin Simple driving circuit Cons Contrast (reset discharging) Luminance (insufficient sustaining discharging) Large portion on addressing  Difficult to adapt for high resolution, faster than 30Hz sequences Challenge : improving the AWD (Address While Display) scheme proposed by Jae Sung Kim (SNU), Ph.D. thesis (2004)