A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rate
This paper proposes a novel pixel circuit and driving scheme that adopts low-temperature polycrystalline silicon and oxide thin-film transistors (LTPO TFTs) for mobile devices using active-matrix organic light-emitting diode (AMOLED) displays. The proposed pixel circuit and driving scheme provide un...
| Main Authors: | , , , , , , , , , |
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| Format: | Article |
| Language: | English |
| Published: |
Taylor & Francis Group
2023-10-01
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| Series: | Journal of Information Display |
| Subjects: | |
| Online Access: | https://www.tandfonline.com/doi/10.1080/15980316.2023.2213848 |
| _version_ | 1797682950473515008 |
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| author | Jung Chul Kim I. Sak Lee Hyung Tae Kim Jong Bin An Jae Sung Kim Juhn Suk Yoo Han Wook Hwang Hyun Chul Choi Yong Min Ha Hyun Jae Kim |
| author_facet | Jung Chul Kim I. Sak Lee Hyung Tae Kim Jong Bin An Jae Sung Kim Juhn Suk Yoo Han Wook Hwang Hyun Chul Choi Yong Min Ha Hyun Jae Kim |
| author_sort | Jung Chul Kim |
| collection | DOAJ |
| description | This paper proposes a novel pixel circuit and driving scheme that adopts low-temperature polycrystalline silicon and oxide thin-film transistors (LTPO TFTs) for mobile devices using active-matrix organic light-emitting diode (AMOLED) displays. The proposed pixel circuit and driving scheme provide uniform luminance and render flicker invisible at variable refresh rates (VRRs) from 1 to 120 Hz. Using the proposed pixel circuit with extended compensation time (tCOMP) improves the luminance uniformity at a high-frame rate. The proposed driving scheme applies a voltage to the driving TFTs (D-TFTs) higher than the programmed data voltage during the skip frame. This reduces the flicker caused by the hysteresis of D-TFTs during low-frame rate driving. A 6.0-inch quad high-definition (QHD) LTPO-based AMOLED display was fabricated using the new pixel circuit and driving scheme. Experimental results of the proposed pixel circuit show that the standard deviation of luminance was reduced from 0.056 to 0.008 by extending tCOMP from 2 to 8 µs. The flicker level was −51 dB, so there was no visual artifact during 1 Hz driving. A flicker-free LTPO-based AMOLED display with low power consumption is possible; driving can proceed in 1–120 Hz range. |
| first_indexed | 2024-03-12T00:07:19Z |
| format | Article |
| id | doaj.art-9a7f1bc9cf4648f9b82350ad27bb461d |
| institution | Directory Open Access Journal |
| issn | 1598-0316 2158-1606 |
| language | English |
| last_indexed | 2024-03-12T00:07:19Z |
| publishDate | 2023-10-01 |
| publisher | Taylor & Francis Group |
| record_format | Article |
| series | Journal of Information Display |
| spelling | doaj.art-9a7f1bc9cf4648f9b82350ad27bb461d2023-09-16T10:56:05ZengTaylor & Francis GroupJournal of Information Display1598-03162158-16062023-10-0124428329810.1080/15980316.2023.2213848A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rateJung Chul Kim0I. Sak Lee1Hyung Tae Kim2Jong Bin An3Jae Sung Kim4Juhn Suk Yoo5Han Wook Hwang6Hyun Chul Choi7Yong Min Ha8Hyun Jae Kim9The School of Electrical and Electronic Engineering, Yonsei University, Seoul, South KoreaThe School of Electrical and Electronic Engineering, Yonsei University, Seoul, South KoreaThe School of Electrical and Electronic Engineering, Yonsei University, Seoul, South KoreaThe School of Electrical and Electronic Engineering, Yonsei University, Seoul, South KoreaLG Display, Co., Ltd., Paju, Sourth KoreaLG Display, Co., Ltd., Paju, Sourth KoreaLG Display, Co., Ltd., Paju, Sourth KoreaLG Display, Co., Ltd., Paju, Sourth KoreaLG Display, Co., Ltd., Paju, Sourth KoreaThe School of Electrical and Electronic Engineering, Yonsei University, Seoul, South KoreaThis paper proposes a novel pixel circuit and driving scheme that adopts low-temperature polycrystalline silicon and oxide thin-film transistors (LTPO TFTs) for mobile devices using active-matrix organic light-emitting diode (AMOLED) displays. The proposed pixel circuit and driving scheme provide uniform luminance and render flicker invisible at variable refresh rates (VRRs) from 1 to 120 Hz. Using the proposed pixel circuit with extended compensation time (tCOMP) improves the luminance uniformity at a high-frame rate. The proposed driving scheme applies a voltage to the driving TFTs (D-TFTs) higher than the programmed data voltage during the skip frame. This reduces the flicker caused by the hysteresis of D-TFTs during low-frame rate driving. A 6.0-inch quad high-definition (QHD) LTPO-based AMOLED display was fabricated using the new pixel circuit and driving scheme. Experimental results of the proposed pixel circuit show that the standard deviation of luminance was reduced from 0.056 to 0.008 by extending tCOMP from 2 to 8 µs. The flicker level was −51 dB, so there was no visual artifact during 1 Hz driving. A flicker-free LTPO-based AMOLED display with low power consumption is possible; driving can proceed in 1–120 Hz range.https://www.tandfonline.com/doi/10.1080/15980316.2023.2213848Low-temperature polycrystalline and oxide (LTPO)variable refresh rate (VRR)flickerhysteresis |
| spellingShingle | Jung Chul Kim I. Sak Lee Hyung Tae Kim Jong Bin An Jae Sung Kim Juhn Suk Yoo Han Wook Hwang Hyun Chul Choi Yong Min Ha Hyun Jae Kim A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rate Journal of Information Display Low-temperature polycrystalline and oxide (LTPO) variable refresh rate (VRR) flicker hysteresis |
| title | A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rate |
| title_full | A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rate |
| title_fullStr | A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rate |
| title_full_unstemmed | A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rate |
| title_short | A novel LTPO AMOLED pixel circuit and driving scheme for variable refresh rate |
| title_sort | novel ltpo amoled pixel circuit and driving scheme for variable refresh rate |
| topic | Low-temperature polycrystalline and oxide (LTPO) variable refresh rate (VRR) flicker hysteresis |
| url | https://www.tandfonline.com/doi/10.1080/15980316.2023.2213848 |
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