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ATE524804T1 - Stromgesteuerte elektrooptische vorrichtung, z.b. elektrolumineszente anzeige, mit komplementären steuertransistoren, die gegen änderungen der schwellspannung wirksam sind - Google Patents

Stromgesteuerte elektrooptische vorrichtung, z.b. elektrolumineszente anzeige, mit komplementären steuertransistoren, die gegen änderungen der schwellspannung wirksam sind

Info

Publication number
ATE524804T1
ATE524804T1 AT01305904T AT01305904T ATE524804T1 AT E524804 T1 ATE524804 T1 AT E524804T1 AT 01305904 T AT01305904 T AT 01305904T AT 01305904 T AT01305904 T AT 01305904T AT E524804 T1 ATE524804 T1 AT E524804T1
Authority
AT
Austria
Prior art keywords
threshold voltage
optical device
effective against
electroluminescent display
control transistors
Prior art date
Application number
AT01305904T
Other languages
English (en)
Inventor
Simon Tam
Original Assignee
Seiko Epson Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from GB0016815A external-priority patent/GB2364592A/en
Application filed by Seiko Epson Corp filed Critical Seiko Epson Corp
Application granted granted Critical
Publication of ATE524804T1 publication Critical patent/ATE524804T1/de

Links

Classifications

    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G3/00—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes
    • G09G3/20—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters
    • G09G3/22—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources
    • G09G3/30—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels
    • G09G3/32—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED]
    • G09G3/3208—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED]
    • G09G3/3225—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix
    • G09G3/3233—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix with pixel circuitry controlling the current through the light-emitting element
    • G09G3/3241—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix with pixel circuitry controlling the current through the light-emitting element the current through the light-emitting element being set using a data current provided by the data driver, e.g. by using a two-transistor current mirror
    • G09G3/325—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters using controlled light sources using electroluminescent panels semiconductive, e.g. using light-emitting diodes [LED] organic, e.g. using organic light-emitting diodes [OLED] using an active matrix with pixel circuitry controlling the current through the light-emitting element the current through the light-emitting element being set using a data current provided by the data driver, e.g. by using a two-transistor current mirror the data current flowing through the driving transistor during a setting phase, e.g. by using a switch for connecting the driving transistor to the data driver
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/04—Structural and physical details of display devices
    • G09G2300/0404—Matrix technologies
    • G09G2300/0417—Special arrangements specific to the use of low carrier mobility technology
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0819—Several active elements per pixel in active matrix panels used for counteracting undesired variations, e.g. feedback or autozeroing
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0842—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor
    • G09G2300/0852—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor being a dynamic memory with more than one capacitor
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2300/00—Aspects of the constitution of display devices
    • G09G2300/08—Active matrix structure, i.e. with use of active elements, inclusive of non-linear two terminal elements, in the pixels together with light emitting or modulating elements
    • G09G2300/0809—Several active elements per pixel in active matrix panels
    • G09G2300/0842—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor
    • G09G2300/0861—Several active elements per pixel in active matrix panels forming a memory circuit, e.g. a dynamic memory with one capacitor with additional control of the display period without amending the charge stored in a pixel memory, e.g. by means of additional select electrodes
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/02—Improving the quality of display appearance
    • G09G2320/0271—Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping
    • G09G2320/0276—Adjustment of the gradation levels within the range of the gradation scale, e.g. by redistribution or clipping for the purpose of adaptation to the characteristics of a display device, i.e. gamma correction
    • G—PHYSICS
    • G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
    • G09G—ARRANGEMENTS OR CIRCUITS FOR CONTROL OF INDICATING DEVICES USING STATIC MEANS TO PRESENT VARIABLE INFORMATION
    • G09G2320/00—Control of display operating conditions
    • G09G2320/04—Maintaining the quality of display appearance
    • G09G2320/043—Preventing or counteracting the effects of ageing

Landscapes

  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Computer Hardware Design (AREA)
  • General Physics & Mathematics (AREA)
  • Theoretical Computer Science (AREA)
  • Control Of Indicators Other Than Cathode Ray Tubes (AREA)
  • Control Of El Displays (AREA)
AT01305904T 2000-07-07 2001-07-09 Stromgesteuerte elektrooptische vorrichtung, z.b. elektrolumineszente anzeige, mit komplementären steuertransistoren, die gegen änderungen der schwellspannung wirksam sind ATE524804T1 (de)

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
GB0016815A GB2364592A (en) 2000-03-31 2000-07-07 Pixel driver for an organic electroluminescent device

Publications (1)

Publication Number Publication Date
ATE524804T1 true ATE524804T1 (de) 2011-09-15

Family

ID=9895292

Family Applications (1)

Application Number Title Priority Date Filing Date
AT01305904T ATE524804T1 (de) 2000-07-07 2001-07-09 Stromgesteuerte elektrooptische vorrichtung, z.b. elektrolumineszente anzeige, mit komplementären steuertransistoren, die gegen änderungen der schwellspannung wirksam sind

Country Status (6)

Country Link
US (1) US6919868B2 (de)
EP (1) EP1170719B1 (de)
CN (3) CN1221933C (de)
AT (1) ATE524804T1 (de)
TW (2) TWI282080B (de)
WO (1) WO2002005255A1 (de)

Families Citing this family (54)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR100637433B1 (ko) * 2004-05-24 2006-10-20 삼성에스디아이 주식회사 발광 표시 장치
US8633878B2 (en) 2001-06-21 2014-01-21 Japan Display Inc. Image display
JP4982014B2 (ja) 2001-06-21 2012-07-25 株式会社日立製作所 画像表示装置
JP2003043998A (ja) 2001-07-30 2003-02-14 Pioneer Electronic Corp ディスプレイ装置
JP4075505B2 (ja) * 2001-09-10 2008-04-16 セイコーエプソン株式会社 電子回路、電子装置、及び電子機器
WO2003027997A1 (fr) * 2001-09-21 2003-04-03 Semiconductor Energy Laboratory Co., Ltd. Ecran et procede de fonctionnement associe
GB0130176D0 (en) * 2001-12-18 2002-02-06 Koninkl Philips Electronics Nv Electroluminescent display device
KR100469070B1 (ko) * 2002-02-19 2005-02-02 재단법인서울대학교산학협력재단 능동 매트릭스 유기물 발광 다이오드 디스플레이 화소구조
KR100452114B1 (ko) * 2002-04-15 2004-10-12 한국과학기술원 화소 회로 및 이를 이용한 유기 발광 다이오드 표시장치
JP3989763B2 (ja) 2002-04-15 2007-10-10 株式会社半導体エネルギー研究所 半導体表示装置
KR100638304B1 (ko) * 2002-04-26 2006-10-26 도시바 마쯔시따 디스플레이 테크놀로지 컴퍼니, 리미티드 Ｅｌ 표시 패널의 드라이버 회로
TWI345211B (en) * 2002-05-17 2011-07-11 Semiconductor Energy Lab Display apparatus and driving method thereof
TWI360098B (en) * 2002-05-17 2012-03-11 Semiconductor Energy Lab Display apparatus and driving method thereof
US7184034B2 (en) 2002-05-17 2007-02-27 Semiconductor Energy Laboratory Co., Ltd. Display device
US7474285B2 (en) * 2002-05-17 2009-01-06 Semiconductor Energy Laboratory Co., Ltd. Display apparatus and driving method thereof
US7170479B2 (en) * 2002-05-17 2007-01-30 Semiconductor Energy Laboratory Co., Ltd. Display device and driving method thereof
JP2004095671A (ja) * 2002-07-10 2004-03-25 Seiko Epson Corp 薄膜トランジスタ、スイッチング回路、アクティブ素子基板、電気光学装置、電子機器、サーマルヘッド、液滴吐出ヘッド、印刷装置、薄膜トランジスタ駆動発光表示装置
JP4123084B2 (ja) * 2002-07-31 2008-07-23 セイコーエプソン株式会社 電子回路、電気光学装置、及び電子機器
US7352133B2 (en) * 2002-08-05 2008-04-01 Semiconductor Energy Laboratory Co., Ltd. Light emitting device
JP4416456B2 (ja) * 2002-09-02 2010-02-17 キヤノン株式会社 エレクトロルミネッセンス装置
TWI354975B (en) * 2002-09-05 2011-12-21 Semiconductor Energy Lab Light emitting device and driving method thereof
KR100803412B1 (ko) * 2002-10-31 2008-02-13 가시오게산키 가부시키가이샤 표시장치 및 표시장치 구동방법
EP1577870B1 (de) * 2002-12-27 2010-09-29 Semiconductor Energy Laboratory Co., Ltd. Halbleiterbauelement und dieses verwendendeanzeigeeinrichtung
JP4571375B2 (ja) * 2003-02-19 2010-10-27 東北パイオニア株式会社 アクティブ駆動型発光表示装置およびその駆動制御方法
KR101101340B1 (ko) * 2003-02-28 2012-01-02 가부시키가이샤 한도오따이 에네루기 켄큐쇼 반도체 장치 및 그 구동방법
US7612749B2 (en) * 2003-03-04 2009-11-03 Chi Mei Optoelectronics Corporation Driving circuits for displays
GB0307320D0 (en) * 2003-03-29 2003-05-07 Koninkl Philips Electronics Nv Active matrix display device
WO2004097782A1 (en) * 2003-05-02 2004-11-11 Koninklijke Philips Electronics N.V. Active matrix oled display device with threshold voltage drift compensation
JP4467910B2 (ja) * 2003-05-16 2010-05-26 東芝モバイルディスプレイ株式会社 アクティブマトリクス型表示装置
JP4484451B2 (ja) * 2003-05-16 2010-06-16 奇美電子股▲ふん▼有限公司 画像表示装置
KR100742063B1 (ko) * 2003-05-26 2007-07-23 가시오게산키 가부시키가이샤 전류생성공급회로 및 표시장치
JP4304585B2 (ja) * 2003-06-30 2009-07-29 カシオ計算機株式会社 電流生成供給回路及びその制御方法並びに該電流生成供給回路を備えた表示装置
JP4103079B2 (ja) * 2003-07-16 2008-06-18 カシオ計算機株式会社 電流生成供給回路及びその制御方法並びに電流生成供給回路を備えた表示装置
KR100599726B1 (ko) * 2003-11-27 2006-07-12 삼성에스디아이 주식회사 발광 표시 장치 및 그 표시 패널과 구동 방법
JP4297438B2 (ja) * 2003-11-24 2009-07-15 三星モバイルディスプレイ株式會社 発光表示装置，表示パネル，及び発光表示装置の駆動方法
GB0400216D0 (en) * 2004-01-07 2004-02-11 Koninkl Philips Electronics Nv Electroluminescent display devices
GB2411758A (en) 2004-03-04 2005-09-07 Seiko Epson Corp Pixel circuit
TW200540774A (en) 2004-04-12 2005-12-16 Sanyo Electric Co Organic EL pixel circuit
KR100649253B1 (ko) * 2004-06-30 2006-11-24 삼성에스디아이 주식회사 발광 표시 장치와, 그 표시 패널 및 구동 방법
KR100570774B1 (ko) * 2004-08-20 2006-04-12 삼성에스디아이 주식회사 발광표시 장치의 표시 데이터용 메모리 관리 방법
KR100612392B1 (ko) * 2004-10-13 2006-08-16 삼성에스디아이 주식회사 발광 표시 장치 및 발광 표시 패널
KR100688801B1 (ko) * 2004-11-22 2007-03-02 삼성에스디아이 주식회사 델타 화소회로 및 발광 표시장치
KR100600345B1 (ko) * 2004-11-22 2006-07-18 삼성에스디아이 주식회사 화소회로 및 그를 이용한 발광 표시장치
JP4364849B2 (ja) * 2004-11-22 2009-11-18 三星モバイルディスプレイ株式會社 発光表示装置
KR100688802B1 (ko) * 2004-11-22 2007-03-02 삼성에스디아이 주식회사 화소 및 발광 표시장치
KR101127851B1 (ko) * 2005-06-30 2012-03-21 엘지디스플레이 주식회사 발광 표시장치 및 이의 구동방법
US8629819B2 (en) 2005-07-14 2014-01-14 Semiconductor Energy Laboratory Co., Ltd. Semiconductor device and driving method thereof
TWI485681B (zh) * 2005-08-12 2015-05-21 Semiconductor Energy Lab 顯示裝置
JP2009237041A (ja) * 2008-03-26 2009-10-15 Sony Corp 画像表示装置及び画像表示方法
JP5073544B2 (ja) * 2008-03-26 2012-11-14 富士フイルム株式会社 表示装置
KR101789602B1 (ko) * 2014-12-31 2017-10-26 엘지디스플레이 주식회사 유기발광 표시장치 및 그의 구동 방법
TWI587699B (zh) * 2015-06-02 2017-06-11 國立中山大學 感光電路及其控制方法
CN105654906B (zh) * 2016-01-26 2018-08-03 京东方科技集团股份有限公司 像素电路及其驱动方法、显示面板以及显示装置
CN109003575B (zh) * 2018-08-20 2020-04-24 京东方科技集团股份有限公司 像素电路及其驱动方法、显示基板

Family Cites Families (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3443151A (en) * 1965-11-30 1969-05-06 Monsanto Co Electrical control circuits
US4712021A (en) * 1985-06-28 1987-12-08 Deutsche Itt Industries Gmbh Cmos inverter
DE69112698T2 (de) * 1990-05-07 1996-02-15 Fujitsu Ltd Anzeigeeinrichtung von höher Qualität mit aktiver Matrix.
TW209895B (de) * 1990-11-26 1993-07-21 Semiconductor Energy Res Co Ltd
EP0597226A1 (de) 1992-11-09 1994-05-18 Motorola, Inc. Gegentaktadressierung einer Matrix
US5714968A (en) * 1994-08-09 1998-02-03 Nec Corporation Current-dependent light-emitting element drive circuit for use in active matrix display device
US5525923A (en) * 1995-02-21 1996-06-11 Loral Federal Systems Company Single event upset immune register with fast write access
JP3619299B2 (ja) 1995-09-29 2005-02-09 パイオニア株式会社 発光素子の駆動回路
JPH09306685A (ja) * 1996-05-20 1997-11-28 Harumi Suzuki インバータ回路を用いた照明装置
KR100541253B1 (ko) 1997-02-17 2006-07-10 세이코 엡슨 가부시키가이샤 표시장치
US6462722B1 (en) 1997-02-17 2002-10-08 Seiko Epson Corporation Current-driven light-emitting display apparatus and method of producing the same
US5903246A (en) 1997-04-04 1999-05-11 Sarnoff Corporation Circuit and method for driving an organic light emitting diode (O-LED) display
US5952789A (en) 1997-04-14 1999-09-14 Sarnoff Corporation Active matrix organic light emitting diode (amoled) display pixel structure and data load/illuminate circuit therefor
GB9812742D0 (en) * 1998-06-12 1998-08-12 Philips Electronics Nv Active matrix electroluminescent display devices
GB9923261D0 (en) * 1999-10-02 1999-12-08 Koninkl Philips Electronics Nv Active matrix electroluminescent display device
TW561445B (en) * 2001-01-02 2003-11-11 Chi Mei Optoelectronics Corp OLED active driving system with current feedback

Also Published As

Publication number Publication date
TW200302444A (en) 2003-08-01
CN1658266A (zh) 2005-08-24
CN100481185C (zh) 2009-04-22
CN1877680A (zh) 2006-12-13
EP1170719B1 (de) 2011-09-14
TWI282080B (en) 2007-06-01
CN1221933C (zh) 2005-10-05
EP1170719A1 (de) 2002-01-09
WO2002005255A1 (en) 2002-01-17
US6919868B2 (en) 2005-07-19
TWI277056B (en) 2007-03-21
CN1388952A (zh) 2003-01-01
US20020021293A1 (en) 2002-02-21

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