A low power 640×480 OLED-on-silicon chip design that used in microdisplay was presented. A novel pixel circuit was proposed to meet the special requirement of OLED-on-silicon. The novel pixel consists of three tr...A low power 640×480 OLED-on-silicon chip design that used in microdisplay was presented. A novel pixel circuit was proposed to meet the special requirement of OLED-on-silicon. The novel pixel consists of three transistors and one capacitor （3T 1C）. It has simple structure and can effectively reduce the current glitch generated during the AC driving from 55 pA to 7.5 pA, so that it can improve the precision of grayscale of display as well as extend the lifetime of （]）LED material. Except for the pixel array, low power row driver, column driver and other functional modules were also integrated on the chip. Several techniques were adopted to reduce the power consumption and frequency requirement of the chip. Finally, a 16×3×12 resolution chip was fabricated with standard 0.35 μm CMOS process of CSM and the chip can operate correctly.展开更多
A new active digital pixel circuit for CMOS image sensor is designed consisting of four components: a photo-transducer, a preamplifier, a sample & hold (S & H) circuit and an A/D converter with an inverter. It...A new active digital pixel circuit for CMOS image sensor is designed consisting of four components: a photo-transducer, a preamplifier, a sample & hold (S & H) circuit and an A/D converter with an inverter. It is optimized by simulation and adjustment based on 2 μm standard CMOS process. Each circuit of the components is designed with specific parameters. The simulation results of the whole pixel circuits show that the circuit has such advantages as low distortion, low power consumption, and improvement of the output performances by using an inverter.展开更多
The suitability of indium gallium zinc oxide(IGZO) thin-film transistors(TFT) for implementation of active matrix display of organic light emitting diodes(AMOLED) compensation pixel circuits is addressed in this paper...The suitability of indium gallium zinc oxide(IGZO) thin-film transistors(TFT) for implementation of active matrix display of organic light emitting diodes(AMOLED) compensation pixel circuits is addressed in this paper. In particular, the impact of mobility on compensating performance for the implementation in AMOLED pixel circuits is investigated. Details of the effective mobility modeling using the power law of gate-to-source voltage are provided, and parameters are extracted according to the measured current-to-voltage data of IGZO TFT samples. The investigated AMOLED pixel circuit consists of 4 switching TFTs, 1 driving TFT, and 1 capacitor. A "source-follower" structure is used for the threshold voltage extraction of the driving transistor. A new timing diagram is proposed; thus the current error of the pixel circuit is almost independent of the effective mobility. But, to improve the precision of the threshold voltage extraction of the driving transistor, the mobility is required to be greater than5 cm^2 V^(-1) s^(-1). On the other hand, the optimized storage capacitance is reversely proportional to the effective mobility. Thus, the layout area of the pixel circuit can be decreased from 100 × 100 to 100 × 68 μm2, with the effective mobility increased from 10 to50 cm^2 V^(-1) s^(-1). Therefore, IGZO TFT is a good alternative backplane technology for AMOLED displays, and a higher effective mobility is preferred for high compensation performance and compact layout.展开更多
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...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.展开更多
This paper presents a new compensation pixe] circuit suitable for active-matrix organic light-emitting diode （AMOLED） stereoscopic three dimensional （3D~ displays with shutter glasses. The simultaneous emissio~ met...This paper presents a new compensation pixe] circuit suitable for active-matrix organic light-emitting diode （AMOLED） stereoscopic three dimensional （3D~ displays with shutter glasses. The simultaneous emissio~ method was used to solve the crosstalk problem, in which the periods of initialization and threshold voltage detectio11 occur for each pixel of whole panel simultaneously. Furthermore, there was no need of the periods of initialization and threshold voltage detection from the second frame beginning by one-time detection method. employing threshold voltage The non-uniformity of the proposed pixel circuit was considerably low with an average value of 8.6% measured from 20 discrete proposed pixel circuits integrated by In-Zn-O thin film transistors （IZO TFTs）. It was shown that the OLED current almost remains constant for the number of frames up to 70 even the threshold voltage detection period only exists in the first frame.展开更多
A new equivalent circuit model of organic-light-emitting-diode （OLED） is proposed. As the single- diode model is able to approximate OLED behavior as well as the multiple-diode model, the new model will be built bas...A new equivalent circuit model of organic-light-emitting-diode （OLED） is proposed. As the single- diode model is able to approximate OLED behavior as well as the multiple-diode model, the new model will be built based on it. In order to make sure that the experimental and simulated data are in good agreement, the constant resistor is exchanged for an exponential resistor in the new model. Compared with the measured data and the results of the other two OLED SPICE models, the simulated I-V characteristics of the new model match the measured data much better. This new model can be directly incorporated into an SPICE circuit simulator and presents good accuracy over the whole operating voltage.展开更多
After approximately half a century of development, HgCdTe infrared detectors have become the first choice for high performance infrared detectors, which are widely used in various industry sectors, including military ...After approximately half a century of development, HgCdTe infrared detectors have become the first choice for high performance infrared detectors, which are widely used in various industry sectors, including military tracking, military reconnaissance, infrared guidance, infrared warning, weather forecasting, and resource detection. Further development in infrared applications requires future HgCdTe infrared detectors to exhibit features such as larger focal plane array format and thus higher imaging resolution. An effective approach to develop HgCdTe infrared detectors with a larger array format size is to develop the small pixel technology. In this article, we present a review on the developmental history and current status of small pixel technology for HgCdTe infrared detectors, as well as the main challenges and potential solutions in developing this technology. It is predicted that the pixel size of long-wave HgCdTe infrared detectors can be reduced to5 μm, while that of mid-wave HgCdTe infrared detectors can be reduced to 3 μm. Although significant progress has been made in this area, the development of small pixel technology for HgCdTe infrared detectors still faces significant challenges such as flip-chip bonding, interconnection, and charge processing capacity of readout circuits. Various approaches have been proposed to address these challenges, including three-dimensional stacking integration and readout circuits based on microelectromechanical systems.展开更多
介绍了一种具有2×2像元合并功能的红外读出电路(10μm中心间距)。该电路兼具高分辨率和高帧频的特点,可以满足远距离搜索和近距离跟踪识别两种应用模式下的需求。像元合并前,读出电路的阵列规格为1280×1024,像元中心距为10μm...介绍了一种具有2×2像元合并功能的红外读出电路(10μm中心间距)。该电路兼具高分辨率和高帧频的特点,可以满足远距离搜索和近距离跟踪识别两种应用模式下的需求。像元合并前,读出电路的阵列规格为1280×1024,像元中心距为10μm,空间分辨率高,可用于近距离跟踪识别模式。像元合并后,阵列规格变为640×512,像元中心距变为20μm,灵敏度高,可用于远距离搜索模式。此外,这种电路采用串口输入控制方式,具有积分后读出(Integrate Then Read,ITR)/积分同时读出(Integrate While Read,IWR)工作模式切换、4/8通道可选、翻转和功耗控制等功能。本电路采用GF 0.18μm工艺进行设计。仿真结果表明,在像元合并后,读出电路可达到的最大帧频变为原来的2倍。展开更多
有机发光二极管(O rgan ic L ight Em itting D iode,OLED)由于高对比度、高亮度、超薄、低功耗、宽视野、快响应速度等特性,日益引起人们的兴趣。通过对部分周边驱动电路集成于衬底的2英寸(5.08 cm,64×3×80)有源矩阵显示屏(A...有机发光二极管(O rgan ic L ight Em itting D iode,OLED)由于高对比度、高亮度、超薄、低功耗、宽视野、快响应速度等特性,日益引起人们的兴趣。通过对部分周边驱动电路集成于衬底的2英寸(5.08 cm,64×3×80)有源矩阵显示屏(Active M atrix OLED,AMOLED)上像素驱动电路的仿真,确定彩色OLED显示屏维持白平衡时R、G、B三种OLED所需的驱动电压、电流等工作参数。OLED的发光亮度和电压并不是线性关系,为了维持显示屏的色彩均衡性,对图像数据编码进行校正,保证了灰阶电压与发光亮度呈线性变化。从BMP格式的文件中提取出图像数据部分,进行数据变换,生成符合INTEL HEX文件格式并且满足D/A输出要求的数据文件,刻录到E2PROM中,完成外围驱动电路所需要的图像数据准备。AMOLED显示屏采用逐行扫描的显示方式,因此外围驱动电路的目的是要在行、列扫描有效的同时,为每个像素送入相应的灰阶数据。现在,OLED专用驱动芯片比较少见,而液晶驱动芯片具有集成度高,电压输出范围大等优点,尤其是其内部集成了数据移位寄存器、数据锁存器、D/A转换器等电路,所以设计了基于FPGA和TFT-LCD液晶驱动芯片的外围驱动电路,实现了AMOLED显示屏的彩色图像显示。展开更多
基金Project(10ZCKFGX00200) supported by the Tianjin Science and Technology Supporting Plan,ChinaProject supported by the Fundamental Research Funds for the Central Universities of China
文摘A low power 640×480 OLED-on-silicon chip design that used in microdisplay was presented. A novel pixel circuit was proposed to meet the special requirement of OLED-on-silicon. The novel pixel consists of three transistors and one capacitor （3T 1C）. It has simple structure and can effectively reduce the current glitch generated during the AC driving from 55 pA to 7.5 pA, so that it can improve the precision of grayscale of display as well as extend the lifetime of （]）LED material. Except for the pixel array, low power row driver, column driver and other functional modules were also integrated on the chip. Several techniques were adopted to reduce the power consumption and frequency requirement of the chip. Finally, a 16×3×12 resolution chip was fabricated with standard 0.35 μm CMOS process of CSM and the chip can operate correctly.
文摘A new active digital pixel circuit for CMOS image sensor is designed consisting of four components: a photo-transducer, a preamplifier, a sample & hold (S & H) circuit and an A/D converter with an inverter. It is optimized by simulation and adjustment based on 2 μm standard CMOS process. Each circuit of the components is designed with specific parameters. The simulation results of the whole pixel circuits show that the circuit has such advantages as low distortion, low power consumption, and improvement of the output performances by using an inverter.
基金supported by National Natural Science Foundation of China (No. 61404002)the Shenzhen Municipal Scientific Program (No. JCYJ20150626111117384)
文摘The suitability of indium gallium zinc oxide(IGZO) thin-film transistors(TFT) for implementation of active matrix display of organic light emitting diodes(AMOLED) compensation pixel circuits is addressed in this paper. In particular, the impact of mobility on compensating performance for the implementation in AMOLED pixel circuits is investigated. Details of the effective mobility modeling using the power law of gate-to-source voltage are provided, and parameters are extracted according to the measured current-to-voltage data of IGZO TFT samples. The investigated AMOLED pixel circuit consists of 4 switching TFTs, 1 driving TFT, and 1 capacitor. A "source-follower" structure is used for the threshold voltage extraction of the driving transistor. A new timing diagram is proposed; thus the current error of the pixel circuit is almost independent of the effective mobility. But, to improve the precision of the threshold voltage extraction of the driving transistor, the mobility is required to be greater than5 cm^2 V^(-1) s^(-1). On the other hand, the optimized storage capacitance is reversely proportional to the effective mobility. Thus, the layout area of the pixel circuit can be decreased from 100 × 100 to 100 × 68 μm2, with the effective mobility increased from 10 to50 cm^2 V^(-1) s^(-1). Therefore, IGZO TFT is a good alternative backplane technology for AMOLED displays, and a higher effective mobility is preferred for high compensation performance and compact layout.
文摘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.
文摘This paper presents a new compensation pixe] circuit suitable for active-matrix organic light-emitting diode （AMOLED） stereoscopic three dimensional （3D~ displays with shutter glasses. The simultaneous emissio~ method was used to solve the crosstalk problem, in which the periods of initialization and threshold voltage detectio11 occur for each pixel of whole panel simultaneously. Furthermore, there was no need of the periods of initialization and threshold voltage detection from the second frame beginning by one-time detection method. employing threshold voltage The non-uniformity of the proposed pixel circuit was considerably low with an average value of 8.6% measured from 20 discrete proposed pixel circuits integrated by In-Zn-O thin film transistors （IZO TFTs）. It was shown that the OLED current almost remains constant for the number of frames up to 70 even the threshold voltage detection period only exists in the first frame.
基金supported by the Major State Basic Research Development Program of China(No.2010CB327701)
文摘A new equivalent circuit model of organic-light-emitting-diode （OLED） is proposed. As the single- diode model is able to approximate OLED behavior as well as the multiple-diode model, the new model will be built based on it. In order to make sure that the experimental and simulated data are in good agreement, the constant resistor is exchanged for an exponential resistor in the new model. Compared with the measured data and the results of the other two OLED SPICE models, the simulated I-V characteristics of the new model match the measured data much better. This new model can be directly incorporated into an SPICE circuit simulator and presents good accuracy over the whole operating voltage.
文摘After approximately half a century of development, HgCdTe infrared detectors have become the first choice for high performance infrared detectors, which are widely used in various industry sectors, including military tracking, military reconnaissance, infrared guidance, infrared warning, weather forecasting, and resource detection. Further development in infrared applications requires future HgCdTe infrared detectors to exhibit features such as larger focal plane array format and thus higher imaging resolution. An effective approach to develop HgCdTe infrared detectors with a larger array format size is to develop the small pixel technology. In this article, we present a review on the developmental history and current status of small pixel technology for HgCdTe infrared detectors, as well as the main challenges and potential solutions in developing this technology. It is predicted that the pixel size of long-wave HgCdTe infrared detectors can be reduced to5 μm, while that of mid-wave HgCdTe infrared detectors can be reduced to 3 μm. Although significant progress has been made in this area, the development of small pixel technology for HgCdTe infrared detectors still faces significant challenges such as flip-chip bonding, interconnection, and charge processing capacity of readout circuits. Various approaches have been proposed to address these challenges, including three-dimensional stacking integration and readout circuits based on microelectromechanical systems.
文摘介绍了一种具有2×2像元合并功能的红外读出电路(10μm中心间距)。该电路兼具高分辨率和高帧频的特点,可以满足远距离搜索和近距离跟踪识别两种应用模式下的需求。像元合并前,读出电路的阵列规格为1280×1024,像元中心距为10μm,空间分辨率高,可用于近距离跟踪识别模式。像元合并后,阵列规格变为640×512,像元中心距变为20μm,灵敏度高,可用于远距离搜索模式。此外,这种电路采用串口输入控制方式,具有积分后读出(Integrate Then Read,ITR)/积分同时读出(Integrate While Read,IWR)工作模式切换、4/8通道可选、翻转和功耗控制等功能。本电路采用GF 0.18μm工艺进行设计。仿真结果表明,在像元合并后,读出电路可达到的最大帧频变为原来的2倍。
文摘有机发光二极管(O rgan ic L ight Em itting D iode,OLED)由于高对比度、高亮度、超薄、低功耗、宽视野、快响应速度等特性,日益引起人们的兴趣。通过对部分周边驱动电路集成于衬底的2英寸(5.08 cm,64×3×80)有源矩阵显示屏(Active M atrix OLED,AMOLED)上像素驱动电路的仿真,确定彩色OLED显示屏维持白平衡时R、G、B三种OLED所需的驱动电压、电流等工作参数。OLED的发光亮度和电压并不是线性关系,为了维持显示屏的色彩均衡性,对图像数据编码进行校正,保证了灰阶电压与发光亮度呈线性变化。从BMP格式的文件中提取出图像数据部分,进行数据变换,生成符合INTEL HEX文件格式并且满足D/A输出要求的数据文件,刻录到E2PROM中,完成外围驱动电路所需要的图像数据准备。AMOLED显示屏采用逐行扫描的显示方式,因此外围驱动电路的目的是要在行、列扫描有效的同时,为每个像素送入相应的灰阶数据。现在,OLED专用驱动芯片比较少见,而液晶驱动芯片具有集成度高,电压输出范围大等优点,尤其是其内部集成了数据移位寄存器、数据锁存器、D/A转换器等电路,所以设计了基于FPGA和TFT-LCD液晶驱动芯片的外围驱动电路,实现了AMOLED显示屏的彩色图像显示。
