A CMOS log-polar or foveated image sensor for use in mobile robotic and machine vision applications has been designed, fabricated, and tested. The sensor benefits from a high degree of integration, minimal power consu...
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A CMOS log-polar or foveated image sensor for use in mobile robotic and machine vision applications has been designed, fabricated, and tested. The sensor benefits from a high degree of integration, minimal power consumption, and ease of manufacture due to the use of a standard 1.2-mu m ASIC CMOS process. The sensor if composed of two distinct CMOS images arrays which together solve the problem of obtaining good image resolution over a wide field of view. High resolution sensing is accomplished with a 40 x 40 array of individual pixels each measuring 9.6 mu m on a side. A wide field of view is provided by an array of 64 x 16 pixels arranged on a log-polar grid. The maximum measured dynamic range for the fabricated log-polar array is 46 dB, while the lowest observed fixed-pattern noise is 0.5% of saturation. Combined power consumption of both arrays is under 2 mW when operating from a single 5-V supply at a frame rat of 30 frames/s.
A numerical method to model the surface of a re. owed square microlens is proposed to improve the simulation accuracy of photosensitivity for an image sensor. To verify the proposed method, a re. owed square microlens...
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A numerical method to model the surface of a re. owed square microlens is proposed to improve the simulation accuracy of photosensitivity for an image sensor. To verify the proposed method, a re. owed square microlens with base size of 4.8 x 4.8 mm and sag height of 1.55 mu m was fabricated and the modelling accuracy was compared and analysed.
Low light imaging is being researched intensively. The applications of increased sensitivity sensors expand to biomedicine, security, and communications providing low-cost and effective alternatives to common imaging ...
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Low light imaging is being researched intensively. The applications of increased sensitivity sensors expand to biomedicine, security, and communications providing low-cost and effective alternatives to common imaging techniques based on microscopes, intensifiers, etc. Lowering the inherent noise floor and achieving a higher sensitivity in a complementary metal-oxide semiconductor (CMOS) sensor are found at the focus of the scientific society, and new solutions emerge quickly. Methods such as output averaging, active reset, and active column sensing lower the noise floor but fail to provide the sensitivity boost, which requires a substantial signal amplification. The already proposed solutions, combining high gain and noise suppression, still fall short of the sensitivity that would enable detecting a few electrons. This brief proposes a very sensitive pixel that is designed to capture an ultralow illumination using three stage amplifiers' configuration, which allows for an effective reset operation and in-pixel analog-to-digital conversion. The provided measurement results prove the functionality of the proposed pixel architecture, indicating a remarkable sensitivity of 355 V/lx*s and a detection limit of 3 electrons, achieved consuming only 6 mu W per pixel.
In this letter, color mixings of a CMOS image sensor with air-gap-guard-ring (AGGR) and conventional structures were investigated in 0.18-mu m CMOS image sensor technology. As the light incident angle is increased fro...
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In this letter, color mixings of a CMOS image sensor with air-gap-guard-ring (AGGR) and conventional structures were investigated in 0.18-mu m CMOS image sensor technology. As the light incident angle is increased from 0 degrees to 15 degrees, conventional pixel shows serious color mixing. For example, the maximum photo responses of blue, green1, green2, and red pixels are shifted from 490 to 520 nm, 530 to 500 rim, 530 to 600 run, and 600 to 580 nm, respectively. However, pixels with AGGR not only keep correct spectral response without peak shift but also achieve 5 %-50% crosstalk reduction, thus preventing the sensor from color mixing efficiently.
A sub-0.5e(rms)(-) temporal read noise VGA (640Hx480V) CMOS image sensor has been integrated in a standard 0.18 mu m 4PM CMOS process. The low noise performance is achieved exclusively through circuit optimization wit...
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A sub-0.5e(rms)(-) temporal read noise VGA (640Hx480V) CMOS image sensor has been integrated in a standard 0.18 mu m 4PM CMOS process. The low noise performance is achieved exclusively through circuit optimization without any process refinements. The presented imager relies on a 4T pixel of 6.5 mu m pitch with a properly sized and biased thin oxide PMOS source follower. A full characterization of the proposed image sensor, at room temperature, is presented. With a pixel bias of 1.5 mu A the sensor chip features an input-referred noise histogram from 0.25e(rms)(-) to a few e(rms)(-) peaking at 0.48e(rms)(-). The imager features a full well capacity of 6400e(-) and its frame rate can go up to 80 fps. It also features a fixed pattern noise as low as 0.77%, a lag of 0.1% and a dark current of 5.6e(-)/s. It is also shown that the implementation of the in-pixel n-well does not impact the quantum efficiency of the pinned photo-diode.
Heat pipe cooling systems are widely used for thermal control in space engineering. From design perspective, they must be designed to ensure structural safety under launch environment and minimize force transmitted to...
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Heat pipe cooling systems are widely used for thermal control in space engineering. From design perspective, they must be designed to ensure structural safety under launch environment and minimize force transmitted to components or structures resulting from thermal deformation of heat pipe in the space. The heat pipe should also provide sufficient thermal capacity to transfer heat from components with high heat dissipation to the radiator. In this study, we examine the heat pipe cooling system for thermal control of the spacebome image sensor. The efficiency of the heat pipe thermal interface has been verified using numerical simulation and burn-out test of the heat pipe performed in the space simulated vacuum environment. On-orbit thermal analysis has also been performed to evaluate whether the design satisfies temperature requirements for the image sensor. The analysis results show that the proposed heat pipe cooling system guarantees both structural safety and thermal control performance. (C) 2013 Elsevier Masson SAS. All rights reserved.
A kind of specially designed MOS image sensor (IS) with high sensitivity is introduced in the paper. The IS is used to receive moire signals to form a phase-modulated signal. With dynamic phase discriminating and subd...
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ISBN:
(纸本)0819412295
A kind of specially designed MOS image sensor (IS) with high sensitivity is introduced in the paper. The IS is used to receive moire signals to form a phase-modulated signal. With dynamic phase discriminating and subdivision, a very high resolution and precision can be achieved. This special image sensor is valuable in practical designing of high resolution ($LSEQ 0.1 $mu@m), high precision, and low cost grating displacement transducer.
We have fabricated a novel image sensor using Cu(In,Ga)Se-2 (CIGS). A combined process of dry etching using HBr and Ar gasses and wet etching using dilute HCl solution was developed as isolation process of CIGS photod...
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We have fabricated a novel image sensor using Cu(In,Ga)Se-2 (CIGS). A combined process of dry etching using HBr and Ar gasses and wet etching using dilute HCl solution was developed as isolation process of CIGS photodiode deposited at 400 degrees C. Etchant residues of the dry etching, which consist of Cu complex, were almost completely cleaned using the wet etching process and favorable vertical side wall of CIGS films was obtained without mechanical damages. As a result, high performance image sensors with low leakage current of similar to 10(-8) A/cm(2) and wide wavelength range up to similar to 1240 nm were achieved. The developed image sensor consisted of 352 x 288 pixels with 10 mu m x 10 mu m pixel sizes, was able to capture clear images of night scenes. (C) 2008 Elsevier B.V. All rights reserved.
A nonsilicide source/drain pixel is proposed for high performance 0.25-mum CMOS image sensor. By using organic material spin coat and etch back, silicide is only formed on poly gate which can be used as interconnectio...
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A nonsilicide source/drain pixel is proposed for high performance 0.25-mum CMOS image sensor. By using organic material spin coat and etch back, silicide is only formed on poly gate which can be used as interconnection, not for source/drain region that solve the optical opaque and undesirably large junction leakage of silicide, The performance of MOSFET has little change due to the high sheet resistance of nonsilicide source/drain. With HP annealing and double ion implanted source/drain junction, the dark current can be further reduced. The novel pixel (three transistors, 3.3 mum x 3.3 mum, fill factor: 28%) shows low dark current (less than 0.5 fA per pixel at 25 degreesC) and high photoresponse.
A photoconductor micrometer using a row of linear image sensors is described, which is able to determine the dimension of the shadow of an object transversely illuminated by a parallel beam of light. The described equ...
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A photoconductor micrometer using a row of linear image sensors is described, which is able to determine the dimension of the shadow of an object transversely illuminated by a parallel beam of light. The described equipment is easily tailored to specific uses and may find applications in variation measurement of exposed vessels, for example.
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