共查询到16条相似文献,搜索用时 236 毫秒
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基于CMOS图像传感器的多斜率积分模式 总被引:1,自引:0,他引:1
CMOS图像传感器由于器件本身的特点,相比CCD传感器,其动态范围较小。以CYPRESS公司生产的高性能CMOS图像传感器IBIS5-A-1300为研究对象,对其多斜率积分原理进行研究,提出了采用同步快门多斜率积分的方法来扩展CMOS图像传感器的动态范围。以FPGA+DSP为系统的硬件处理平台,给出了多斜率积分驱动时序的具体设计思路和方法,并在QuartusⅡ7.0环境下对所设计的驱动时序进行功能仿真。采用所设计的多斜率积分时序驱动,将CMOS图像传感器的动态范围由原来单斜率积分模式下的64 dB扩展到了90 dB。实验结果表明,采用多斜率积分模式可以实现动态范围扩展的要求。 相似文献
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一种高性能X射线CMOS图像传感器的研究 总被引:1,自引:0,他引:1
研制了一种采用电流镜积分读出电路和相关双采样电路的X射线CMOS图像传感器(NEW-X-IS),传感器像元由采用CMOS工艺的光电二极管实现,光电二极管产生的光电流通过电流镜放大后在像元外的电容上积分,经相关双采样电路抑制噪声后,由CMOS移位寄存器和多路开关电路输出视频信号.对采用2 μm CMOS工艺研制的64位实验线阵进行参数测试,结果表明NEW-X-IS具有较小的非均匀性、较低的暗噪声、较大的单位面积响应度、较高的输出电压和较宽的动态范围.将其应用于一个实验系统中,得到了不同密度、不同尺寸材料的视频信号波形. 相似文献
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精细导星仪(FGS)是空间天文望远镜精密稳像系统高精度姿态信息的快速检测装置,CMOS图像传感器的成像效果直接影响精细导星仪姿态信息的解算精度.而实际工作时,CMOS成像器件存在最佳的读出范围,超出此范围的入射光强与光生电子数的线性度低,无法获取有效星点来满足后级的质心坐标解算.为解决这一问题,提出一种估算不同星等最佳积分时间的方法,并将积分时间作为探测器参数选择与调整的主要依据.测量结果表明,像元暗电流的读出码值和探测器面阵RMS噪声值均随积分时间的增加而增加.依据星点光斑分布模型给出常用星等的最佳积分时间范围,结合星点的分布情况,得出7等星在视场范围内的星数约为7颗,论证了小型CMOS器件对星斑的探测能力. 相似文献
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提出了一种梯度自适应的宽动态CMOS图像传感器像素结构。该像素结构采用多路分流设计,改变了3T-APS图像传感器的单线性响应率;根据不同的光照强度自适应调整响应率,在低照度时具有较大的响应率,在高照度时具有较小的响应率,从而增大了像素的动态范围。该像素结构简单,无需额外复杂的控制电路即可实现对光照强度的自适应梯度响应。基于0.18 μm 1P4M SMIC工艺,采用SILVACO TCAD仿真软件进行电路设计和仿真。结果表明,该CMOS图像传感器像素结构电路的动态范围可达到112.36 dB。 相似文献
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设计了一种基于电容反馈跨阻放大器(CTIA)的长线列CMOS图像传感器。为减小器件功耗和面积,采用基于单端四管共源共栅运算放大器。为提高信号读出速率,采用没有体效应的PMOS源跟随器,同时减小PMOS管的宽长比,有效减小了输出总线寄生电容的影响。在版图设计上,采用顶层金属走线,降低寄生电阻和电容,提高了长线列CMOS图像传感器的读出速率和输出线性范围。采用0.35μm 3.3V标准CMOS工艺对传感器进行流片,得到器件像元阵列为5×1 030,像元尺寸为20μm×20μm。测试结果表明:该传感器在积分时间为1ms、读出速率为4MHz的情况下工作稳定,其线性度达到98%,线性动态范围为76dB。 相似文献
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Akahane N. Sugawa S. Adachi S. Mori K. Ishiuchi T. Mizobuchi K. 《Solid-State Circuits, IEEE Journal of》2006,41(4):851-858
In a CMOS image sensor featuring a lateral overflow integration capacitor in a pixel, which integrates the overflowed charges from a fully depleted photodiode during the same exposure, the sensitivity in nonsaturated signal and the linearity in saturated overflow signal have been improved by introducing a new pixel circuit and its operation. The floating diffusion capacitance of the CMOS image sensor is as small as that of a four transistors type CMOS image sensor because the lateral overflow integration capacitor is located next to the reset switch. A 1/3-inch VGA format (640/sup H//spl times/480/sup V/ pixels), 7.5/spl times/7.5 /spl mu/m/sup 2/ pixel color CMOS image sensor fabricated through 0.35-/spl mu/m two-poly three-metal CMOS process results in a 100 dB dynamic range characteristic, with improved sensitivity and linearity. 相似文献
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天基系统CMOS图像传感器成像距离研究 总被引:1,自引:0,他引:1
CMOS图像传感器以其集成度高、功耗低、抗辐射能力强和成本低等优势已经逐渐被应用到天基空间目标可见光监测系统中.作为系统成像能力和识别能力的重要指标,准确地分析和评估CMOS图像传感器的成像距离是天基系统设计的前提和基础.在对CMOS和CCD传感器进行对比的基础上,从信噪比的角度出发,以深空作为背景,根据光度学和辐射度学的基本原理,对基于CMOS图像传感器的天基空间目标监测系统的成像距离进行了详细分析和公式推导,并以STAR-1000CMOS图像传感器为例验证了理论模型和计算公式的正确性,最后对进一步提高CMOS图像传感器成像距离的方法进行了简要分析. 相似文献
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A technical investigation, research and im-plementation is presented to correct column fixed pattern noise and black level in large array Complementary metal oxide semiconductor (CMOS) image sensor. Through making a comparison among reported solution, and give large array CMOS image sensor design and considerations, according to our previous analysis on non-ideal factor and error source of piecewise Digital to analog converter (DAC) in multi-channels, an improving accurate piecewise DAC with adaptive switch technique is developed. The research theory has verified by a high dynamic range and low column Fixed pattern noise (FPN) CMOS image sensor prototype chip, which consisting of 8320×8320 pixel array was designed and fabricated in 55nm CMOS 1P4M standard process. The chip active area is 48mm×48mm with a pixel size of 5.7μm×5.7μm. The measured results achieved a high intrinsic dynamic range of 75dB, a low FPN and black level of 0.06%, a low photo response non-uniformity of 1.5% respectively, and an excellent raw sample image taken by the prototype sensor. 相似文献
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针对空间低照度环境下,互补金属氧化物半导体(CMOS)相机成像视觉效果不佳的问题,基于张量优化的图像融合方法研制一款高动态范围的微光相机。分析基于科学互补金属氧化物半导体(sCMOS)图像传感器亮暗场双通道ADC的电路特性,利用同源双通道图像数据构建三阶特征张量,通过对特征张量的平行因子分析,以融合图像动态范围最优为评价函数,引入拉格朗日乘数法作为张量分解的优化算法,实现实时的高分辨力高动态范围成像。研制一款基于LTN4625的微光相机,并进行成像实验。仿真实验结果表明,相机实现了50帧/s,4 608×2 592像素的高分辨力高动态范围成像,图像动态范围从低增益数据的5.2 dB和高增益数据的11.4 dB提高到了54.7 dB。该设计是一种微弱光环境下动态响应范围高、成像效果好的微光相机设计方法。 相似文献
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A 1/3-inch, 800H x 600v pixels, 5.6 x 5.6 mum2 color CMOS image sensor with three photocurrent integrations in pixel photodiodes, pixel lateral overflow capacitors and column capacitors fabricated in a 0.18 mum 2P3M CMOS technology has been reported. The image sensor operates using photodiode integrations and lateral overflow integrations in low light condition and achieves a wide dynamic range (DR) performance of around 100 dB in its one exposure. The wide DR performance in one exposure makes high S/N ratios at the signal switching points in the multiple exposures. The CMOS image sensor also operates using the column capacitor integration in very bright light condition. In the column capacitor integration, the photocurrents generated at the photodiodes are directly integrated at the column capacitors in each column line. The combination of two exposures using the photodiode integrations and the lateral overflow integrations and one exposure using the column capacitors leads to the whole linear photo-electric conversion responses from low light to very bright light region. The fabricated image sensor achieves a high S/N ratio, a fully linear response and over 180 dB DR in the incident light ranging from about 1.4 x 10-2 lx to about 2.4 x 107 lx. 相似文献