共查询到20条相似文献,搜索用时 31 毫秒
1.
基于低温多晶硅薄膜晶体管的AMOLED交流像素电路 总被引:1,自引:1,他引:0
This work presents a new voltage programmed pixel circuit for an active-matrix organic light-emitting diode(AMOLED) display.The proposed pixel circuit consists of six low temperature polycrystalline silicon thinfilm transistors(LTPS TFTs),one storage capacitor,and one OLED,and is verified by simulation work using HSPICE software.Besides effectively compensating for the threshold voltage variation of the driving TFT and OLED,the proposed pixel circuit offers an AC driving mode for the OLED,which can suppress the degradation of the OLED.Moreover,a high contrast ratio can be achieved by the proposed pixel circuit since the OLED does not emit any light except for the emission period. 相似文献
2.
A new a-Si:H TFT pixel circuit compensating the threshold voltage shift of a-Si:H TFT and OLED for active matrix OLED 总被引:1,自引:0,他引:1
Jae-Hoon Lee Ji-Hoon Kim Min-Koo Han 《Electron Device Letters, IEEE》2005,26(12):897-899
We propose a new hydrogenated amorphous silicon thin-film transistor (a-Si:H TFT) pixel circuit for an active matrix organic light-emitting diode (AMOLED) employing a voltage programming. The proposed a-Si:H TFT pixel circuit, which consists of five switching TFTs, one driving TFT, and one capacitor, successfully minimizes a decrease of OLED current caused by threshold voltage degradation of a-Si:H TFT and OLED. Our experimental results, based on the bias-temperature stress, exhibit that the output current for OLED is decreased by 7% in the proposed pixel, while it is decreased by 28% in the conventional 2-TFT pixel. 相似文献
3.
《Electron Device Letters, IEEE》2006,27(9):743-745
This letter presents a new pixel design and driving method for active-matrix organic light-emitting diode (AMOLED) displays using low-temperature polycrystalline silicon thin-film transistors (TFTs). The proposed pixel circuit consists of five TFTs and one capacitor to eliminate the variation in the threshold voltage of the TFTs, and the drop in the supply voltage in a single frame operation by the source-follower-type connection and the bootstrap. The proposed pixel circuit has been verified to realize uniform output current by the simulation work using the HSPICE software. The novel pixel design has great potential for use in large-size and high-resolution AMOLED displays. 相似文献
4.
具有顶部发光结构的AMOLED交流驱动电路 总被引:1,自引:1,他引:0
A new voltage programmed pixel circuit with top emission design for active-matrix organic lightemitting diode(AMOLED) displays is presented and verified by HSPICE simulations.The proposed pixel circuit consists of five poly-Si TFTs,and can effectively compensate for the threshold voltage variation of the driving TFT.Meanwhile,the proposed pixel circuit offers an AC driving mode for the OLED by the two adjacent pulse voltage sources,which can suppress the degradation of the OLED.Moreover,a high contrast ratio can be achieved by the proposed pixel circuit since the OLED does not emit any light except for the emission period. 相似文献
5.
A new voltage-programmed pixel circuit using hydrogenated amorphous silicon (a-Si:H) thin-film transistors (TFTs) for active-matrix organic light-emitting diodes (AMOLEDs) is presented. In addition to compensating for the shift in threshold voltage of TFTs, the circuit is capable of compensating for OLED luminance degradation by employing the shift in OLED voltage as a feedback of OLED degradation 相似文献
6.
Hau-Yan Lu Ting-Chang Chang Ya-Hsiang Tai Po-Tsun Liu Sien Chi 《Display Technology, Journal of》2007,3(4):398-403
A new pixel design and driving method for active-matrix organic light-emitting diode (AMOLED) display using low-temperature polycrystalline silicon thin-film transistor (LTPS-TFT) is proposed. The new circuit consists of five TFTs and one capacitor to eliminate the variation in the threshold voltage of the TFTs, and the drop in the supply voltage in a single frame operation. The proposed pixel circuit has been verified to realize uniform output current by the simulation work using HSPICE software. The simulated error rate of the output current is also discussed in this paper. The novel pixel design has great potential for use in large size and high resolution AMOLED displays. 相似文献
7.
This paper presents a new poly-Si pixel circuit employing AC driving mode for active matrix organic light-emitting diode (AMOLED) displays. The proposed pixel circuit, which consists of one driving thin-film tran- sistor (TFT), three switching TFTs, and one storage capacitor, can effectively compensate for the threshold voltage variation in poly-Si and the OLED degradation. As there is no light emission, except for during the emitting period, and a small number of devices used in the proposed pixel circuit, a high contrast ratio and a high pixel aperture ratio can be easily achieved. Simulation results by SMART-SPICE software show that the non-uniformity of the OLED current for the proposed pixel circuit is significantly decreased (〈 10%) with an average value of 2.63%, while that of the conventional 2T1C is 103%. Thus the brightness uniformity of AMOLED displays can be improved by using the proposed pixel circuit. 相似文献
8.
A new voltage-programmed driving scheme named the mixed parallel addressing scheme is presented for AMOLED displays, in which one compensation interval can be divided into the first compensation frame and the consequent N-1 post-compensation frames without periods of initialization and threshold voltage detection. The proposed driving scheme has the advantages of both high speed and low driving power due to the mixture of the pipeline technology and the threshold voltage one-time detection technology. Corresponding to the proposed driving scheme, we also propose a new voltage-programmed compensation pixel circuit, which consists of five TFTs and two capacitors(5T2C). In-Zn-O thin-film transistors(IZO TFTs) are used to build the proposed 5T2C pixel circuit. It is shown that the non-uniformity of the proposed pixel circuit is considerably reduced compared with that of the conventional 2T1C pixel circuit. The number of frames(N) preserved in the proposed driving scheme are measured and can be up to 35 with the variation of the OLED current remaining in an acceptable range. Moreover, the proposed voltage-programmed driving scheme can be more valuable for an AMOLED display with high resolution, and may also be applied to other compensation pixel circuits. 相似文献
9.
A new a-Si:H thin-film transistor pixel circuit for active-matrix organic light-emitting diodes 总被引:1,自引:0,他引:1
We propose a new pixel circuit using hydrogenated amorphous silicon (a-Si:H) thin-film transistors (TFTs), composed of three switching and one driving TFT, for active-matrix organic light-emitting diodes (AMOLEDs) with a voltage source method. The circuit simulation results based on the measured threshold voltage shift of a-Si:H TFTs by gate-bias stress indicate that this circuit compensates for the threshold voltage shifts over 10000 h of operation. 相似文献
10.
Chih-Lung Lin Tsung-Ting Tsai 《Electron Device Letters, IEEE》2007,28(6):489-491
A novel voltage driving method using three thin-film transistors (TFTs) for active-matrix organic light-emitting diodes (OLEDs) is presented and verified by automatic integrated circuit modeling SPICE simulation. The proposed novel 3-TFT pixel circuit, which successfully compensates for the threshold voltage variations, uses few TFTs with simplified control signals, and the current nonuniformity of the proposed circuit is 0.19% to 1.99% throughout the entire data range. To compensate for variations in OLED current, the proposed circuit utilizes a novel driving scheme that uses a diode connection current source with a biased voltage. 相似文献
11.
《Microelectronics Journal》2015,46(10):923-927
In this paper, pixel circuit using mirroring structure with Indium–Gallium–Zinc oxide (IGZO) thin film transistors (TFTs) for active matrix organic light emitting diode (AMOLED) display is proposed. This pixel circuit consists of only four TFTs, and one capacitor. Due to the mirroring structure, characteristic of the driving TFT can be precisely sensed by the sensing TFT, which is deployed in a discharging path for gate electrode of the driving TFT. This discharging process is strongly dependent on threshold voltage (VT) and effective mobility of the sensing TFT. Circuit operating details are discussed, and compensation effects for threshold voltage shift and mobility variations are verified through numerical derivation and SPICE simulations. Furthermore, compared with conventional schematics, the proposed pixel circuit might have much simplified external driving circuits, and it is a promising alternative solution of high performance AMOLED display. 相似文献
12.
A New Poly-Si TFT Current-Mirror Pixel for Active Matrix Organic Light Emitting Diode 总被引:1,自引:0,他引:1
《Electron Device Letters, IEEE》2006,27(10):830-833
A new poly-Si thin-film-transistor (TFT) current-mirror-active-matrix-organic-light-emitting-diode (AMOLED) pixel, which successfully compensates for the variation of the threshold voltage as well as mobility in the excimer laser annealed poly-Si TFT pixel, is designed and fabricated. The OLED current$(I_ OLED)$ of the proposed pixel does not depend on the operating temperature. When the temperature of pixel is increased from 27$^circhboxC$ to 60$^circhboxC$ , the$I_ OLED$ of the new pixel circuit composed of four TFTs and one capacitor increases only about 1.5%, while that of a conventional pixel composed of two TFTs and one capacitor increases about 37%. At room temperature, nonuniformity of the$I_ OLED$ in the proposed circuit was also considerably suppressed at around 9%. We have successfully fabricated a 1.2-in AMOLED panel$(hbox96 times hbox96 times hboxred green blue)$ to evaluate the performance of the proposed pixel. A troublesome residual image caused by the hysteresis phenomenon of the poly-Si TFT was almost eliminated in the proposed AMOLED panel as a result of current programming. 相似文献
13.
Hsiao-Wen Zan Shin-Chin Kao 《Electron Device Letters, IEEE》2008,29(2):155-157
In this letter, the influence of drain bias on the threshold voltage instability in pentacene-based organic thin-film transistors (OTFTs) was studied. By applying different drain biases to adjust the channel carrier concentration in linear mode, the threshold voltage shift was found to be proportional to the carrier concentration. The experimental data can be well quantitatively explained by the drain bias-stress theory developed for a-Si TFTs. The outcome gives the insight of the degradation mechanism of OTFTs and is important for the design of OTFT pixel circuit, OTFT analog amplifiers, or OTFT active loads. 相似文献
14.
A new current-programmed, current-output active TFT image sensor suitable for real-time X-ray imaging (e.g. fluoroscopy) using hydrogenated amorphous silicon (a-Si:H) thin-film-transistor (TFT) technology is introduced. The proposed pixel circuit can successfully compensate for characteristic variations such as mobility and threshold voltage shift in a-Si:H TFTs. Simulation and measurement results show that high on-pixel amplification can be accomplished with this pixel circuit. 相似文献
15.
16.
Ya-Hsiang Tai Bo-Ting Chen Yu-Ju Kuo Chun-Chien Tsai Ko-Yu Chiang Ying-Jyun Wei Huang-Chung Cheng 《Display Technology, Journal of》2005,1(1):100-104
A new pixel circuit design for active matrix organic light-emitting diode (AMOLED), based on the low-temperature polycrystalline silicon thin-film transistors (LTPS-TFTs) is proposed and verified by SPICE simulation. Threshold voltage compensation pixel circuit consisting of four n-type TFTs, one p-type TFT, one additional control signal, and one storage capacitor is used to enhance display image quality. The simulation results show that this pixel circuit has high immunity to the variation of poly-Si TFT characteristics. 相似文献
17.
This letter presents a novel pixel circuit for hydrogenated amorphous silicon (a-Si:H) active matrix organic light-emitting diode displays employing the short-term stress stability characteristics of a-Si:H thin film transistors (TFTs). The pixel circuit uses a programming TFT that is under stress during the programming cycle and unstressed during the drive cycle. The threshold voltage shift (V/sub T/-shift) of the TFT under these conditions is negligible. The programming TFT in turn regulates the current of the drive TFT, and the pixel current therefore becomes independent of the threshold voltage of the drive TFT. 相似文献
18.
《Electron Device Letters, IEEE》2009,30(4):377-379
19.
Shinya Ono Koichi Miwa Yuichi Maekawa Takatoshi Tsujimura 《Electron Devices, IEEE Transactions on》2007,54(3):462-467
In this paper, we propose the threshold-voltage compensation pixel circuit that is composed of two thin-film transistors (TFTs) and one capacitor (2T1C). It not only compensates the deviation of the threshold voltage of the driver TFT but also actualizes the large aperture ratio for organic light-emitting diode (OLED) devices as well as the traditional 2T1C circuit. We show the result of SPICE simulation for the pixel circuit; it indicates that the circuit can allocate the relatively large aperture ratio for OLED devices 相似文献
20.
A scheme of driving active matrix organic light emitting diode (AMOLED) displays with hydrogenated amorphous silicon (a-Si) thin-film transistors (TFTs) is presented. By sending a feedback voltage from each pixel to a column driver during the programming cycle, the driving scheme can compensate for the instability of the TFTs, in particular, the shift in the threshold voltage. Measurement results show no change in the OLED current in the presence of a 1.3-V shift in the threshold voltage. Based on circuit analysis, a simple lead compensator and an accelerating pulse were employed to achieve fast pixel programming for a wide range of OLED currents. Simulation results show a programming time of less than 70 /spl mu/s for OLED currents as low as 50 nA. 相似文献