Journal articles: 'CCD-On-CMOS'

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Zhang, Tao, Xinyang Li, Jianfeng Li, and Zhi Xu. "CMOS Fixed Pattern Noise Elimination Based on Sparse Unidirectional Hybrid Total Variation." Sensors 20, no. 19 (September 28, 2020): 5567. http://dx.doi.org/10.3390/s20195567.

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With the improvement of semiconductor technology, the performance of CMOS Image Sensor has been greatly improved, reaching the same level as that of CCD in dark current, linearity and readout noise. However, due to the production process, CMOS has higher fix pattern noise than CCD at present. Therefore, the removal of CMOS fixed pattern noise has become the research content of many scholars. For current fixed pattern noise (FPN) removal methods, the most effective one is based on optimization. Therefore, the optimization method has become the focus of many scholars. However, most optimization models only consider the image itself, and rarely consider the structural characteristics of FPN. The proposed sparse unidirectional hybrid total variation (SUTV) algorithm takes into account both the sparse structure of column fix pattern noise (CFPN) and the random properties of pixel fix pattern noise (PFPN), and uses adaptive adjustment strategies for some parameters. From the experimental values of PSNR and SSM as well as the rate of change, the SUTV model meets the design expectations with effective noise reduction and robustness.

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Karpov, S., A. Christov, A. Bajat, R. Cunniffe, and M. Prouza. "CHARACTERIZATION OF MODERN CCD AND CMOS SENSORS FOR SKY SURVEYS." Revista Mexicana de Astronomía y Astrofísica Serie de Conferencias 53 (September 1, 2021): 190–97. http://dx.doi.org/10.22201/ia.14052059p.2021.53.38.

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Here we review the efforts we take in a newly established laboratory inside Institute of Physics in Prague in order to characterize modern large-format CCD and CMOS sensors for sky survey applications. While the laboratory is primarily established in order to participate in low-level CCD sensor characterization for LSST project, we also managed to perform a thorough laboratory testing of recently released Andor Marana sCMOS (which is especially interesting for wide-field sky monitoring applications due to its large format, backilluminated design, high achievable frame rate and low read-out noise), as well as detailed measurements of response non-linearity of Moravian Instruments G4-16000 CCD cameras (based on large-format Kodak KAF-16803 chip) used in several robotic telescopes. We brieﬂy review the results acquired on these cameras, as well as hardware and software we developed for the laboratory.

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Ngo, Nguyen Hoai, Kazuhiro Shimonomura, Taeko Ando, Takayoshi Shimura, Heiji Watanabe, Kohsei Takehara, Anh Quang Nguyen, Edoardo Charbon, and Takeharu Goji Etoh. "A Pixel Design of a Branching Ultra-Highspeed Image Sensor." Sensors 21, no. 7 (April 3, 2021): 2506. http://dx.doi.org/10.3390/s21072506.

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A burst image sensor named Hanabi, meaning fireworks in Japanese, includes a branching CCD and multiple CMOS readout circuits. The sensor is backside-illuminated with a light/charge guide pipe to minimize the temporal resolution by suppressing the horizontal motion of signal carriers. On the front side, the pixel has a guide gate at the center, branching to six first-branching gates, each bifurcating to second-branching gates, and finally connected to 12 (=6×2) floating diffusions. The signals are either read out after an image capture operation to replay 12 to 48 consecutive images, or continuously transferred to a memory chip stacked on the front side of the sensor chip and converted to digital signals. A CCD burst image sensor enables a noiseless signal transfer from a photodiode to the in-situ storage even at very high frame rates. However, the pixel count conflicts with the frame count due to the large pixel size for the relatively large in-pixel CCD memory elements. A CMOS burst image sensor can use small trench-type capacitors for memory elements, instead of CCD channels. However, the transfer noise from a floating diffusion to the memory element increases in proportion to the square root of the frame rate. The Hanabi chip overcomes the compromise between these pros and cons.

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Shi, Chenhao. "Applications of CMOS image sensors: Applications and innovations." Applied and Computational Engineering 11, no. 1 (September 25, 2023): 95–103. http://dx.doi.org/10.54254/2755-2721/11/20230216.

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As semiconductor production processes continue to advance, CMOS image sensors are becoming increasingly popular and are gradually replacing traditional CCD sensors as the mainstream option in the market. Because CMOS image sensors adopt the standard CMOS semiconductor production process, which provides advantages such as low static power consumption, large noise tolerance, strong anti-interference ability, and fast working speed. This article is going to provide an overview of CMOS image sensors and examine their various applications. To achieve this, this article will provide some background information on CMOS image sensors, including a discussion of their structure, components, and working principles. A comprehensive literature review was conducted to explore the characteristics and benefits of CMOS image sensors in applications such as intelligent surveillance systems (ISS), space, and medical. This paper also discusses recent advances in CMOS image sensor technology, namely backside illumination, global shutter, and 3D imaging, and their impact on various industries. Despite the advantages of CMOS image sensors, they still have some limitations and shortcomings. Therefore, further progress in industrial development is necessary to improve the quality of these products.

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Qiu, Peng, Yong Zhao, Jie Zheng, Jian-Feng Wang, and Xiao-Jun Jiang. "Research on performances of back-illuminated scientific CMOS for astronomical observations." Research in Astronomy and Astrophysics 21, no. 10 (November 1, 2021): 268. http://dx.doi.org/10.1088/1674-4527/21/10/268.

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Abstract To evaluate performances of a back-illuminated scientific CMOS (sCMOS) camera for astronomical observations, comparison tests between Andor Marana sCMOS and Andor iKon-L 936 CCD cameras were conducted in a laboratory and on a telescope. The laboratory tests showed that the readout noise of the sCMOS camera is about half lower, the dark current is about 17 times higher, the dynamic range is lower in the 12-bit setting and higher in the 16-bit setting, and the linearity and bias stability are comparable relative to those of the CCD camera. In field tests, we observed the open cluster M67 with the sCMOS and CCD cameras on a 60 cm telescope. Unlike the CCD camera, the sCMOS camera has a dual-amplifier architecture. Since a 16-bit image of the sCMOS camera is composed of two 12-bit images sampled with 12-bit high gain and low gain amplifiers simultaneously, it is not real 16-bit output data. The evaluation tests indicated that the dual-amplifier architecture of the sCMOS camera leads to a decline of photometric stability by about six times around specific pixel counts. For photometry of bright objects with similar magnitudes that require high frame rates, the sCMOS camera under 12-bit setting is a good choice. Therefore, the sCMOS camera is fitted with survey observations of variable objects requiring short exposure times, mostly less than 1 s, and high frame rates. It also satisfies the requirements for an offset guiding instrument owing to its high sensitivity, high temporal resolution and high stability.

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Stepanov, Valery R., and Dmitry M. Nikulin. "COMPARISON OF THE CALCULATED WORKING RANGE OF THE THIRD GENERATION EOS AND MATRIX FOR NEAR IR RANGE." Interexpo GEO-Siberia 6, no. 2 (July 8, 2020): 88–92. http://dx.doi.org/10.33764/2618-981x-2020-6-2-88-92.

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In the course of work on the master's thesis the analysis of daytime and night-time devices was carried out. The analysis showed that devices based on CCD-matrixes prevail in this segment, but the devices of this type cannot be fully called night devices, because the sensitivity of the matrixes used in their designs does not allow to observe without illumination at natural night illumination of 10-3 lux. It is known that IR illumination is a strong unmasking factor.EOS can provide acceptable image quality in natural nightlight. But their use in day-night devices has limitations. Under prolonged exposure to high light, the photocathode of EOS quickly becomes unusable, so when developing a day-night device must provide EOS protection from daylight. Thus it was decided to use CMOS-matrix as an image receiver in the night channel. This, in turn, solves several problems at once. When using the photoreceiver there is no need for mechanical switching between the channels, as there is no danger of light. Also the spectral range of sensitivity of CMOS-matrixes is much more various than that of CCD and EOS that allows to pick up an optimum range of frequencies and to refuse illumination at normal night illumination. In this article a comparison of the calculated range of detection of the device on the basis of EOS of 3 generation with the device in which as the image receiver CMOS-matrix is used.

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Jeon, Gwang Gil. "Performance Analysis on Yamanaka Patterned Color Filter Array." Advanced Materials Research 717 (July 2013): 497–500. http://dx.doi.org/10.4028/www.scientific.net/amr.717.497.

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Generally, a digital camera employs a single CCD or CMOS sensor. In a color imaging device, the color information is usually obtained in sub-sampled patterns of red, green and blue pixels. Thus, full-resolution color is afterward created from this sub-sampled CFA image. This process is normally called as demosaicking. In this paper, we analyze performance of Yamanaka patterned CFA in terms of CPSNR and S-CIELAB. We show the simulation results on test images.

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Seung-Hoon Lee and Tae-Hwan Oh. "Single-chip CMOS CCD camera interface based on digitally controlled capacitor-segment combination." IEEE Transactions on Circuits and Systems II: Analog and Digital Signal Processing 47, no. 11 (2000): 1338–43. http://dx.doi.org/10.1109/82.885145.

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Oprean, Luiza Sonia, and Corina-Mihaela Gruescu. "Design of the Cemented Doublet – Software Application." Robotica & Management 26, no. 1 (2021): 13–16. http://dx.doi.org/10.24193/rm.2021.1.3.

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From optical point of view, an imaging application includes the sensor (CCD or CMOS) and the objective. The simplest objective consists of a cemented doublet. The paper proposes a design algorithm of the doublet and describes a software application based on this algorithm. The results provided by the original software are validated by means of a professional application in optical system analysis.

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Adam, Martin, Eric Hovestreydt, Holger Ott, Bruce Noll, and Michael Ruf. "CMOS – Shutterless Operation Boosts Speed and Quality." Acta Crystallographica Section A Foundations and Advances 70, a1 (August 5, 2014): C682. http://dx.doi.org/10.1107/s2053273314093176.

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CMOS technology based X-ray detectors offer numerous advantages compared to traditionally used CCD detectors: · CMOS sensors are available in larger sizes with a pixel size optimized for X-ray scattering and X-ray diffraction. · CMOS sensors have lower power consumption than CCDs and provide excellent signal-to-noise ratios even when only moderately cooled. This allows the design of air-cooled detectors. Both, low power consumption and no need for cooling-water, lead to minimized pre-installation requirements. · While CCDs use a bucket brigade read-out, CMOS technology does allow continuous direct sensor read-out. These features make modern CMOS based X-ray detectors, such as the PHOTON 100, an excellent solution for single crystal X-ray diffraction (SC-XRD) experiments. In particular, the capability to continually read out pixels provides a new approach for data collection. While CCDs require closing the shutter for each read-out step, introducing system overhead, CMOS based detectors can be operated in shutterless mode, which not only eliminates over-head time but it also reduces mechanical jitter. We will present details on the implementation of shutterless readout in the current state-of-the-art SC-XRD instrumentation, the D8 QUEST and D8 VENTURE systems. Furthermore, the impact of shutterless read-out on data quality and data collection speed will be discussed using examples from chemical crystallography and structural biology.

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Marcelot, O., V. Goiffon, M. Raine, O. Duhamel, M. Gaillardin, R. Molina, and P. Magnan. "Radiation Effects in CCD on CMOS Devices: First Analysis of TID and DDD Effects." IEEE Transactions on Nuclear Science 62, no. 6 (December 2015): 2965–70. http://dx.doi.org/10.1109/tns.2015.2497405.

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XU Shou-long, 徐守龙, 邹树梁 ZOU Shu-liang, 黄有骏 HUANG You-jun, 郭赞 GUO Zan, and 匡雅 KUANG Ya. "Comparative Study on γ-ray Radiation Response Characteristics of CCD and CMOS Pixel Sensor." Chinese Journal of Luminescence 39, no. 6 (2018): 815–22. http://dx.doi.org/10.3788/fgxb20183906.0815.

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Yao, Chen, Yan Xia, and Jiamin Zhu. "Image Enhancement by Frequency Analysis." MATEC Web of Conferences 228 (2018): 02008. http://dx.doi.org/10.1051/matecconf/201822802008.

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Because of lighting or the quality of CMOS/CCD, poor images are often gained, which greatly affect subjective observation. Image enhancement can improve the contrast of poor image. In our paper, we propose a new image enhancement algorithm based on frequency analysis. A central energy of FFT is utilized for computation of image enhancement factors. A linear mapping is used for image mapping. Finally, some experimental results are shown for illustration of our algorithm advantage.

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Marcelot, Olivier, Romain Molina, Matthieu Bouhier, and Pierre Magnan. "Design Impact on Charge Transfer Inefficiency of Surface CCD on CMOS Devices: TCAD and Characterization Study." IEEE Transactions on Electron Devices 63, no. 3 (March 2016): 1099–104. http://dx.doi.org/10.1109/ted.2016.2516045.

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Tölg, T., G. Kemper, and D. Kalinski. "MEDIUM FORMAT CAMERA EVALUATION BASED ON THE LATEST PHASE ONE TECHNOLOGY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 2, 2016): 121–26. http://dx.doi.org/10.5194/isprsarchives-xli-b1-121-2016.

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In early 2016, Phase One Industrial launched a new high resolution camera with a 100 MP CMOS sensor. CCD sensors excel at ISOs up to 200, but in lower light conditions, exposure time must be increased and Forward Motion Compensation (FMC) has to be employed to avoid smearing the images. The CMOS sensor has an ISO range of up to 6400, which enables short exposures instead of using FMC. This paper aims to evaluate the strengths of each of the sensor types based on real missions over a test field in Speyer, Germany, used for airborne camera calibration. The test field area has about 30 Ground Control Points (GCPs), which enable a perfect scenario for a proper geometric evaluation of the cameras. The test field includes both a Siemen star and scale bars to show any blurring caused by forward motion. The result of the comparison showed that both cameras offer high accuracy photogrammetric results with post processing, including triangulation, calibration, orthophoto and DEM generation. The forward motion effect can be compensated by a fast shutter speed and a higher ISO range of the CMOS-based camera. The results showed no significant differences between cameras.

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Tölg, T., G. Kemper, and D. Kalinski. "MEDIUM FORMAT CAMERA EVALUATION BASED ON THE LATEST PHASE ONE TECHNOLOGY." ISPRS - International Archives of the Photogrammetry, Remote Sensing and Spatial Information Sciences XLI-B1 (June 2, 2016): 121–26. http://dx.doi.org/10.5194/isprs-archives-xli-b1-121-2016.

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In early 2016, Phase One Industrial launched a new high resolution camera with a 100 MP CMOS sensor. CCD sensors excel at ISOs up to 200, but in lower light conditions, exposure time must be increased and Forward Motion Compensation (FMC) has to be employed to avoid smearing the images. The CMOS sensor has an ISO range of up to 6400, which enables short exposures instead of using FMC. This paper aims to evaluate the strengths of each of the sensor types based on real missions over a test field in Speyer, Germany, used for airborne camera calibration. The test field area has about 30 Ground Control Points (GCPs), which enable a perfect scenario for a proper geometric evaluation of the cameras. The test field includes both a Siemen star and scale bars to show any blurring caused by forward motion. The result of the comparison showed that both cameras offer high accuracy photogrammetric results with post processing, including triangulation, calibration, orthophoto and DEM generation. The forward motion effect can be compensated by a fast shutter speed and a higher ISO range of the CMOS-based camera. The results showed no significant differences between cameras.

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Shen, Chao, Caiwen Ma, and Wei Gao. "Design of a Ultra-Stable Low-Noise Space Camera Based on a Large Target CMOS Detector and Image Data Analysis." Sensors 22, no. 24 (December 18, 2022): 9991. http://dx.doi.org/10.3390/s22249991.

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To detect faint target stars of 22nd magnitude and above, an astronomical exploration project requires its space camera’s readout noise to be less than 5e− with long-time working stability. Due to the limitation of satellite, the traditional CCD detector-based camera does not meet the requirements, including volume, weight, and power consumption. Thereby, a low-noise ultra-stable camera based on 9 K × 9 K large target surface CMOS is designed to meet the needs. For the first time, the low-noise ultra-stable camera based on CMOS detector will be applied to space astronomy projects, remote sensing imaging, resource survey, atmospheric and oceanic observation and other fields. In this paper, the design of the camera is introduced in detail, and the camera is tested for several rounds at −40 °C; it also undergoes further testing and data analysis. Tests proved super stability and that the readout noise is lower than 4.5e−. Dark current, nonlinearity and PTC indicators meet the requirements of the astronomical exploration project.

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Yamamoto, Seiichi, Masao Yoshino, Kohei Nakanishi, Katsunori Yogo, Kei Kamada, Akira Yoshikawa, Nanase Koshikawa, and Jun Kataoka. "Sub-micrometer real-time imaging of trajectory of alpha particles using GAGG plate and CMOS camera." Journal of Instrumentation 18, no. 10 (October 1, 2023): T10003. http://dx.doi.org/10.1088/1748-0221/18/10/t10003.

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Abstract High-resolution and real-time imaging of the trajectories of alpha particles is desired in nuclear medicine and nuclear engineering. Although an imaging method using a scintillator plate combined with a magnifying unit and a cooled electron multiplying charge-coupled device (EM-CCD) camera is a possible method of obtaining high-resolution trajectory images, the spatial resolution of the system is limited to ∼2 μm. To overcome the spatial resolution limitations of this method on trajectory imaging, we used a cooled complementally metal oxide (CMOS) camera in which the sensor had a much larger number of pixels, which were also smaller. Using the CMOS camera based imaging system, we could measure the trajectories of alpha particles in real time with the spatial resolution of 0.34 μm FWHM. With smoothing of the images to reduce image noise, spatial resolution was still kept to less than 0.75 μm. We conclude that this CMOS camera-based alpha-particle trajectory-imaging system is promising for alpha-particle or other particles imaging where ultrahigh spatial resolution is required.

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Starynska, A. Y., and O. V. Terletsky. "About modulation transfer function of machine vision system based on CMOS and CCD image sensors." Electronics and Communications 19, no. 5 (October 31, 2014): 48–52. http://dx.doi.org/10.20535/2312-1807.2014.19.5.38802.

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Léveillé, Cyril, Kewin Desjardins, Horia Popescu, Boris Vondungbo, Marcel Hennes, Renaud Delaunay, Emmanuelle Jal, et al. "Single-shot experiments at the soft X-FEL FERMI using a back-side-illuminated scientific CMOS detector." Journal of Synchrotron Radiation 29, no. 1 (January 1, 2022): 103–10. http://dx.doi.org/10.1107/s1600577521012303.

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The latest Complementary Metal Oxide Semiconductor (CMOS) 2D sensors now rival the performance of state-of-the-art photon detectors for optical application, combining a high-frame-rate speed with a wide dynamic range. While the advent of high-repetition-rate hard X-ray free-electron lasers (FELs) has boosted the development of complex large-area fast CCD detectors in the extreme ultraviolet (EUV) and soft X-ray domains, scientists lacked such high-performance 2D detectors, principally due to the very poor efficiency limited by the sensor processing. Recently, a new generation of large back-side-illuminated scientific CMOS sensors (CMOS-BSI) has been developed and commercialized. One of these cost-efficient and competitive sensors, the GSENSE400BSI, has been implemented and characterized, and the proof of concept has been carried out at a synchrotron or laser-based X-ray source. In this article, we explore the feasibility of single-shot ultra-fast experiments at FEL sources operating in the EUV/soft X-ray regime with an AXIS-SXR camera equipped with the GSENSE400BSI-TVISB sensor. We illustrate the detector capabilities by performing a soft X-ray magnetic scattering experiment at the DiProi end-station of the FERMI FEL. These measurements show the possibility of integrating this camera for collecting single-shot images at the 50 Hz operation mode of FERMI with a cropped image size of 700 × 700 pixels. The efficiency of the sensor at a working photon energy of 58 eV and the linearity over the large FEL intensity have been verified. Moreover, on-the-fly time-resolved single-shot X-ray resonant magnetic scattering imaging from prototype Co/Pt multilayer films has been carried out with a time collection gain of 30 compared to the classical start-and-stop acquisition method performed with the conventional CCD-BSI detector available at the end-station.

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Mei, Liang, Zheng Kong, Teng Ma, Zhi Liu, Zhenfeng Gong, and Kun Liu. "Recent Advances in Aerosol and Trace Gas Monitoring by Employing the Scheimpflug Lidar Techniques." EPJ Web of Conferences 237 (2020): 07022. http://dx.doi.org/10.1051/epjconf/202023707022.

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Lidar techniques, based on the time-of-flight principle, have been widely employed in atmospheric remote sensing since decades. The Scheimpflug lidar (SLidar) technique, which employing robust high-power laser diodes as light sources and highly integrated CCD/CMOS image sensor as detectors, has been recently developed for various atmospheric applications. Range-resolved atmospheric backscattering signal is obtained by capturing the backscattering imaging of transmitted continuous-wave laser beam based on the Scheimpflug principle. This paper reported recent advances in aerosol and trace gas monitoring by employing the SLidar techniques.

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Zhu, Bo, De Sheng Wen, Wei Gao, Zong Xi Song, and Hua Li. "Research and Design of Color Restoration Algorithm for Demosaicing Bayer Pattern Images." Applied Mechanics and Materials 130-134 (October 2011): 745–51. http://dx.doi.org/10.4028/www.scientific.net/amm.130-134.745.

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This paper analyses the process of obtaining real color image based on a single CCD/CMOS sensor. Bayer CFA Interpolation algorithm and White Balance algorithm are presented. The proposed interpolation algorithm which can obtain better color image and is easier to implement by hardware is provided. In order to cancel chromatic aberration, one White Balance algorithm which aims at sequential image is presented and process of FPGA design is given. Experimental results show that the design works normally. The color of corrected picture is vivid compared to the real world.

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Hasegawa, Kazuya, Kunio Hirata, Tetsuya Shimizu, Nobutaka Shimizu, Takaaki Hikima, Seiki Baba, Takashi Kumasaka, and Masaki Yamamoto. "Development of a shutterless continuous rotation method using an X-ray CMOS detector for protein crystallography." Journal of Applied Crystallography 42, no. 6 (November 17, 2009): 1165–75. http://dx.doi.org/10.1107/s0021889809042277.

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A new shutterless continuous rotation method using an X-ray complementary metal-oxide semiconductor (CMOS) detector has been developed for high-speed, precise data collection in protein crystallography. The principle of operation and the basic performance of the X-ray CMOS detector (Hamamatsu Photonics KK C10158DK) have been shown to be appropriate to the shutterless continuous rotation method. The data quality of the continuous rotation method is comparable to that of the conventional oscillation method using a CCD detector and, furthermore, the combination with fine φ slicing improves the data accuracy without increasing the data-collection time. The new method is more sensitive to diffraction intensity because of the narrow dynamic range of the CMOS detector. However, the strong diffraction spots were found to be precisely measured by recording them on successive multiple images by selecting an adequate rotation step. The new method has been used to successfully determine three protein structures by multi- and single-wavelength anomalous diffraction phasing and has thereby been proved applicable in protein crystallography. The apparatus and method may become a powerful tool at synchrotron protein crystallography beamlines with important potential across a wide range of X-ray wavelengths.

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Huang, Shuo, Xifeng Zheng, Xinyue Mao, Yufeng Chen, and Yu Chen. "Vignetting Compensation Method for CMOS Camera Based on LED Spatial Array." Electronics 13, no. 10 (May 15, 2024): 1936. http://dx.doi.org/10.3390/electronics13101936.

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To solve the problem of pixel light intensity information distortion caused by camera vignetting in optical devices such as CMOS or CCD cameras, existing studies mainly focus on small spatial light fields and point light sources and adopt an integrating sphere and function model for vignetting correction, but it is not suitable for large LED optical composite display devices. Under this background, this paper innovatively proposes a camera vigneting compensation method based on an LED spatial array, independently develops a two-dimensional translation device driven by a high-precision guide rail, uses spatial array technology to obtain the brightness distribution of the corrected display screen to quantify its camera vigneting distortion characteristics, and adopts systematic mathematical operations and iterative compensation strategies. Industry standard tests show that the brightness uniformity of the display has been improved by 5.06%. The above research results have been applied to mass production and industrialization.

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Zhao, Zhigang, Ru Wang, Jianheng Huang, Jinchuan Guo, and Hanben Niu. "Implementation of a Data Acquisition System for 2×2 Fiber Optic Taper Array Coupled Digital X-ray Detector." Open Electrical & Electronic Engineering Journal 8, no. 1 (December 31, 2014): 152–58. http://dx.doi.org/10.2174/1874129001408010152.

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Fiber optic taper (FOP) array coupled digital x-ray detector can be an ideal choice for large area high resolution x-ray imaging, but its data acquisition system is a challenge, for the reasons such as restrictions of hardware design due to the shape of the FOP array, long distance control requirement in x-ray environment, and arrangement of data transmission sequence among multiple CCD/CMOS image sensors. A FPGA and ARM based data acquisition system for 2×2 FOP array coupled x-ray detector was implemented in this paper. We have finished all the procedures involving the data acquisition system, including hardware and PCB design, FPGA design, ARM and PC software development, and so on. The data acquisition process operates in parallel during parameters setting, 4 CMOS image sensors (LUPA-4000) timing driving, and DDR2 SDRAM data buffering, while it works in series when sending data from each FPGA to ARM and from ARM to PC. Experimental results showed that the data acquisition system worked steadily, and whole images of a custom-built calibration plate were achieved by butting images of the four individual CMOS image sensors’ in visible light test environment. This work could be a valuable foundation for realization of all kinds of FOP array coupled digital x-ray detectors.

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Sadchenko, А. V., O. A. Kushnirenko, A. V. Troyanskiy, and Yu A. Savchuk. "Adaptive algorithm for reducing pulse noise level in images from CCTV cameras." Технология и конструирование в электронной аппаратуре, no. 1-2 (2021): 21–27. http://dx.doi.org/10.15222/tkea2021.1-2.21.

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An optical signal is usually converted into an electrical one by using photosensitive matrices with a large number of discrete elements based on charge-coupled device (CCD) technology or CMOS technology. One of the disadvantages of CCD and CMOS technologies is the impulse conversion noise that appears on digitized images, impairing visual perception and significantly reducing the likelihood of correct identification in pattern recognition tasks. Traditionally, impulse noise is removed from images using median filters with a fixed aperture within each iteration of full-format processing. However, such filters reduce the sharpness of the reconstructed image at high noise levels or insufficiently suppress the interference under the same noise conditions. These setbacks call for a need to develop an adaptive median filtering algorithm, which would produce a reconstructed image as a joint result of processing with median filters with different apertures. The essence of this algorithm is to select image areas with different noise levels and process these areas with filters with different apertures. As an objective criterion for assessing the efficiency of the proposed filtering algorithm, the authors used the criterion of the maximum correlation coefficient between noise-free and non-noisy images at various values of the noise variance. The mathematical modeling performed in this study allowed finding that with an increase in the impulse noise variance, the gain of the adaptive median filtering algorithm increases exponentially, in comparison with the algorithms using the filters with a fixed aperture value. The proposed algorithm can be used for pre-preprocessing images intended for recognition by machine vision systems, scanning text, and improving subjective image characteristics, such as sharpness and contrast.

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Han, Zhenghao, Li Li, Weiqi Jin, Xia Wang, Gangcheng Jiao, Xuan Liu, and Hailin Wang. "Denoising and Motion Artifact Removal Using Deformable Kernel Prediction Neural Network for Color-Intensified CMOS." Sensors 21, no. 11 (June 4, 2021): 3891. http://dx.doi.org/10.3390/s21113891.

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Image intensifiers are used internationally as advanced military night-vision devices. They have better imaging performance in low-light-level conditions than CMOS/CCD. The intensified CMOS (ICMOS) was developed to satisfy the digital demand of image intensifiers. In order to make the ICMOS capable of color imaging in low-light-level conditions, a liquid-crystal tunable filter based color imaging ICMOS was developed. Due to the time-division color imaging scheme, motion artifacts may be introduced when a moving target is in the scene. To solve this problem, a deformable kernel prediction neural network (DKPNN) is proposed for joint denoising and motion artifact removal, and a data generation method which generates images with color-channel motion artifacts is also proposed to train the DKPNN. The results show that, compared with other denoising methods, the proposed DKPNN performed better both on generated noisy data and on real noisy data. Therefore, the proposed DKPNN is more suitable for color ICMOS denoising and motion artifact removal. A new exploration was made for low-light-level color imaging schemes.

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Jahn, Izabella J., Alexej Grjasnow, Henry John, Karina Weber, Jürgen Popp, and Walter Hauswald. "Noise Sources and Requirements for Confocal Raman Spectrometers in Biosensor Applications." Sensors 21, no. 15 (July 27, 2021): 5067. http://dx.doi.org/10.3390/s21155067.

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Raman spectroscopy probes the biochemical composition of samples in a non-destructive, non-invasive and label-free fashion yielding specific information on a molecular level. Nevertheless, the Raman effect is very weak. The detection of all inelastically scattered photons with highest efficiency is therefore crucial as well as the identification of all noise sources present in the system. Here we provide a study for performance comparison and assessment of different spectrometers for confocal Raman spectroscopy in biosensor applications. A low-cost, home-built Raman spectrometer with a complementary metal-oxide-semiconductor (CMOS) camera, a middle price-class mini charge-coupled device (CCD) Raman spectrometer and a laboratory grade confocal Raman system with a deeply cooled CCD detector are compared. It is often overlooked that the sample itself is the most important “optical” component in a Raman spectrometer and its properties contribute most significantly to the signal-to-noise ratio. For this purpose, different representative samples: a crystalline silicon wafer, a polypropylene sample and E. coli bacteria were measured under similar conditions using the three confocal Raman spectrometers. We show that biosensor applications do not in every case profit from the most expensive equipment. Finally, a small Raman database of three different bacteria species is set up with the middle price-class mini CCD Raman spectrometer in order to demonstrate the potential of a compact setup for pathogen discrimination.

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Marcelot, Olivier, Magali Estribeau, Vincent Goiffon, Philippe Martin-Gonthier, Franck Corbiere, Romain Molina, Sebastien Rolando, and Pierre Magnan. "Study of CCD Transport on CMOS Imaging Technology: Comparison Between SCCD and BCCD, and Ramp Effect on the CTI." IEEE Transactions on Electron Devices 61, no. 3 (March 2014): 844–49. http://dx.doi.org/10.1109/ted.2014.2298693.

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Hattori, Toshiaki, Fumihiro Dasai, Hikaru Sato, Ryo Kato, and Kazuaki Sawada. "CCD Multi-Ion Image Sensor with Four 128 × 128 Pixels Array." Sensors 19, no. 7 (April 1, 2019): 1582. http://dx.doi.org/10.3390/s19071582.

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A semiconductor array pH image sensor consisting of four separated blocks was fabricated using charged coupled device (CCD) and complementary metal oxide semiconductor (CMOS) technologies. The sensing surface of one of the four blocks was Si3N4 and this block responded to H+. The surfaces of the other three blocks were respectively covered with cation sensitive membranes, which were separately printed with plasticized poly (vinyl chloride) solutions including Na+, K+, and Ca2+ ionophores by using an ink-jet printing method. In addition, each block of the image sensor with 128 × 128 pixels could have a calibration curve generated in each independent measurement condition. The present sensor could measure the concentration image of four kinds of ions (H+, K+, Na +, Ca2+) simultaneously at 8.3 frames per second (fps) in separated regions on a chip.

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Jarzembska, Katarzyna N., Radosław Kamiński, Łukasz Dobrzycki, and Michał K. Cyrański. "First experimental charge density study using a Bruker CMOS-type PHOTON 100 detector: the case of ammonium tetraoxalate dihydrate." Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials 70, no. 5 (October 1, 2014): 847–55. http://dx.doi.org/10.1107/s2052520614017570.

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The aim of this study was to test the applicability of a Bruker AXS CMOS-type PHOTON 100 detector for the purpose of a fine charge density quality data collection. A complex crystal containing oxalic acid, ammonium oxalate and two water molecules was chosen as a test case. The data was collected up to a resolution of 1.31 Å−1with high completeness (89.1%;Rmrg= 0.0274). The multipolar refinement and subsequent quantum theory of atoms in molecules (QTAIM) analysis resulted in a comprehensive description of the charge density distribution in the crystal studied. The residual density maps are flat and almost featureless. It was possible to derive reliable information on intermolecular interactions to model the anharmonic motion of a water molecule, and also to observe the fine details of the charge density distribution, such as polarization on O and H atoms involved in the strongest hydrogen bonds. When compared with our previous statistical study on oxalic acid data collected with the aid of CCD cameras, the complementary metal-oxide semiconductor (CMOS) detector can certainly be classified as a promising alternative in advanced X-ray diffraction studies.

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Pereira, João Antonio, Danilo Damasceno Sabino, and Antonio Eduardo Turra. "Displacement Measurement Using a Unique Digital Camera." Advanced Materials Research 1006-1007 (August 2014): 853–56. http://dx.doi.org/10.4028/www.scientific.net/amr.1006-1007.853.

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This paper presents a noncontact technique for displacement measurement based on the variation of the pixels positions of a target object in the images captured by CCD or CMOS sensor. A video from a moving structure is made and then it is analyzed frame by frame and the variation of the pixels position of the target object in the structure is calculated for each frame and related with the position of the object in the image. The proposed approach is evaluated to measuring vibrations of a reduced scale model of two-floor building lab structure, which focuses on the advantage of using a unique camera for measurements of structural vibrations. The results obtained are compared to reference model and have shown good agreement.

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Naveed, Khuram, Shoaib Ehsan, Klaus D. McDonald-Maier, and Naveed Ur Rehman. "A Multiscale Denoising Framework Using Detection Theory with Application to Images from CMOS/CCD Sensors." Sensors 19, no. 1 (January 8, 2019): 206. http://dx.doi.org/10.3390/s19010206.

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Output from imaging sensors based on CMOS and CCD devices is prone to noise due to inherent electronic fluctuations and low photon count. The resulting noise in the acquired image could be effectively modelled as signal-dependent Poisson noise or as a mixture of Poisson and Gaussian noise. To that end, we propose a generalized framework based on detection theory and hypothesis testing coupled with the variance stability transformation (VST) for Poisson or Poisson–Gaussian denoising. VST transforms signal-dependent Poisson noise to a signal independent Gaussian noise with stable variance. Subsequently, multiscale transforms are employed on the noisy image to segregate signal and noise into separate coefficients. That facilitates the application of local binary hypothesis testing on multiple scales using empirical distribution function (EDF) for the purpose of detection and removal of noise. We demonstrate the effectiveness of the proposed framework with different multiscale transforms and on a wide variety of input datasets.

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Koptev, N. S., and A. A. Pugachev. "TCAD-ASSISTED TECHNIQUE FOR DETERMINING THE PARAMETERS OF MICROLENSES USED IN PHOTOSENSITIVE CCD VLSI." Electronic engineering Series 2 Semiconductor devices 257, no. 2 (2020): 28–36. http://dx.doi.org/10.36845/2073-8250-2020-257-2-28-36.

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In this paper we introduce the simulation technique for photosensitive cell with CCD VLSI microlens with interline transfer. A microlens enhances the photosensitivity of the cell and reduces image blur. The technique is based on the calculation and comparison of the volumetric photogeneration rate integrals of different areas of the photocell, where generated charge carriers are collected and transferred. This technique does not require simulation of the full frame accumulation cycle of the cell, significantly reducing the time of simulation and enabling the evaluation of many design options for microlenses. The technique is implemented in the Sentaurus TCAD (by Synopsys). In the paper we present the results of simulation made for cells with various microlenses. The proposed technique can also be used for the optimization of microlenses of CMOS photodiode VLSI photocells.

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Lin, Xinhang. "Analysis of Electric Sensor for Space Detectors: Mass Spectrometer, Particle Detector and CMOS/CCD Sensor." Highlights in Science, Engineering and Technology 76 (December 31, 2023): 434–40. http://dx.doi.org/10.54097/f9gmck30.

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As a matter of fact, with the participation of government agencies and the exploration of private enterprises, space exploration is undergoing rapid development as well as change in recent years. With this in mind, these trends will continue to promote human exploration and utilization of space, providing more opportunities for scientific research, commercial applications and exploration. In order to realize accuracy observation, high precision detectors are necessary to be developed and implemented. To be specific, a large number of electric sensors are applied on the space detectors, including mass spectrometer, particle detector as well as CMOS/CCD image sensor, etc. On this basis, this paper presents the principles, structures and applications of these three electric sensors in detail. According to the analysis, this study also analyzes the existing shortcomings of the state-of-art facilities as well as proposes future developments. Overall, these results shed light on guiding further exploration of space detectors.

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Rosenberger, Maik, Chen Zhang, Pavel Votyakov, Marc Preißler, and Gunther Notni. "EMVA 1288 Camera characterisation and the influences of radiometric camera characteristics on geometric measurements." ACTA IMEKO 5, no. 4 (December 30, 2016): 81. http://dx.doi.org/10.21014/acta_imeko.v5i4.356.

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Over the past decades, a large number of imaging sensors based mostly on CCD or CMOS technology were developed. Datasheets provided by their developers are usually written on their own standards and no universal figure of merit can be drawn from them for comparison purposes. The EMVA 1288 is a standard aims to overcome this problem by setting parameters and experimental setup for radiometric characterisation of cameras. An implementation of an experimental setup and software environment for radiometric characterisation of imaging sensors following the guidelines of the EMVA 1288 is presented here. Using simulations, the influences and impact of several EMVA 1288 parameters on geometric measurements can be estimated. This paper also presents a signal model and image acquisition chain; measurements of radiometric characteristics of an image sensor; and sensor evaluation for geometric measurements, where the aforementioned influences on geometric measurements are discussed.

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Sun, Ke Mei, and Chun He Yu. "Work Piece Length Measure System Based on Image." Advanced Materials Research 301-303 (July 2011): 1066–71. http://dx.doi.org/10.4028/www.scientific.net/amr.301-303.1066.

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Corporation work piece length measure system based on digital image processing technology. CCD vidicon is used as the image capture equipment. Image signal are converted into 8 bits digital code stream by CMOS image sensor chip OV9650. DSP chip of TI is used as the core of image processing in the scheme. Peripheral SDRAM are expanded through peripheral bus to save the large amounts of temporary data in data processing to reduce the time for image processing. Median filtering is adopted in image enhance of the object image. The length of rectangle work piece can be measured in the distance by untouched way by improved edge recognition algorithm in real time. The measurement result is displayed by LCD. Meanwhile the measure system communicates with PC through communication interface. It has been proved that the system can guarantee real-time and high accurate. It’s a typical instance of DSP and digital image processing technology used in industry.

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Cao, Hongtao, Xingfa Gu, Xiangqin Wei, Tao Yu, and Haifeng Zhang. "Lookup Table Approach for Radiometric Calibration of Miniaturized Multispectral Camera Mounted on an Unmanned Aerial Vehicle." Remote Sensing 12, no. 24 (December 8, 2020): 4012. http://dx.doi.org/10.3390/rs12244012.

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Over recent years, miniaturized multispectral cameras mounted on an unmanned aerial vehicle (UAV) have been widely used in remote sensing. Most of these cameras are integrated with low-cost, image-frame complementary metal-oxide semiconductor (CMOS) sensors. Compared to the typical charged coupled device (CCD) sensors or linear array sensors, consumer-grade CMOS sensors have the disadvantages of low responsivity, higher noise, and non-uniformity of pixels, which make it difficult to accurately detect optical radiation. Therefore, comprehensive radiometric calibration is crucial for quantitative remote sensing and comparison of temporal data using such sensors. In this study, we examine three procedures of radiometric calibration: relative radiometric calibration, normalization, and absolute radiometric calibration. The complex features of dark current noise, vignetting effect, and non-uniformity of detector response are analyzed. Further, appropriate procedures are used to derive the lookup table (LUT) of correction factors for these features. Subsequently, an absolute calibration coefficient based on an empirical model is used to convert the digital number (DN) of images to radiance unit. Due to the radiometric calibration, the DNs of targets observed in the image are more consistent than before calibration. Compared to the method provided by the manufacturer of the sensor, LUTs facilitate much better radiometric calibration. The root mean square error (RMSE) of measured reflectance in each band (475, 560, 668, 717, and 840 nm) are 2.30%, 2.87%, 3.66%, 3.98%, and 4.70% respectively.

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Subhash, Hrebesh Molly. "Full-Field and Single-Shot Full-Field Optical Coherence Tomography: A Novel Technique for Biomedical Imaging Applications." Advances in Optical Technologies 2012 (April 5, 2012): 1–26. http://dx.doi.org/10.1155/2012/435408.

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Since its introduction, optical coherence tomography (OCT) technology has advanced dramatically in various field of both clinical and fundamental research. Full-field and Single-shot full-field OCT (FF-OCT and SS-FF-OCT) are alternative OCT concepts, which aims to improve the image acquisition speed and to simplify the optical setup of conventional point-scan OCT by realizing direct line field or full-field sample imaging onto an array or line detector such as CCD or CMOS camera. FF-OCT and SS-FF-OCT are based on bulk optics Linnik-type Michelson interferometer with relatively high numerical aperture (NA) microscopic objectives. This paper will give you an overview of the principle of various types of FF-OCT and SS-FF-OCT techniques and its associated system design concept and image reconstruction algorithms.

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Wang, Ping Jiang, Ya Ting Huang, Fang Yu Peng, Jiang Fei Qi, and Bin Li. "A Seam Measurement Method Based on Micro Depth of Field for Laser Welding." Applied Mechanics and Materials 121-126 (October 2011): 3107–12. http://dx.doi.org/10.4028/www.scientific.net/amm.121-126.3107.

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For the seam feature measurement of the tight butt joint without misalignment in laser welding, current vision sensor cannot obtain the seam gap width and seam position stably and reliably. In this paper, a seam measurement method based on the micro depth of field is proposed. A four times optical magnification lens, a CCD/CMOS camera and an external LED lighting unit are used to constitute the measure system, which can be used for the tight butt joint for laser welding. Experiment indicated that it can obtain the seam gap width and seam position stably and correctly. With the method, seam surface normal vector also can be measured. The measurement accuracy for the seam gap width and seam position is 5 µm and 6 µm, respectively. Furthermore, the narrowest welding seam gap that can be measured by this method is 0.02 mm, which is fully satisfied the demand of the seam measurement in laser welding.

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Skubalska-Rafajłowicz, Ewa. "Random Projection RBF Nets for Multidimensional Density Estimation." International Journal of Applied Mathematics and Computer Science 18, no. 4 (December 1, 2008): 455–64. http://dx.doi.org/10.2478/v10006-008-0040-9.

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Random Projection RBF Nets for Multidimensional Density EstimationThe dimensionality and the amount of data that need to be processed when intensive data streams are observed grow rapidly together with the development of sensors arrays, CCD and CMOS cameras and other devices. The aim of this paper is to propose an approach to dimensionality reduction as a first stage of training RBF nets. As a vehicle for presenting the ideas, the problem of estimating multivariate probability densities is chosen. The linear projection method is briefly surveyed. Using random projections as the first (additional) layer, we are able to reduce the dimensionality of input data. Bounds on the accuracy of RBF nets equipped with a random projection layer in comparison to RBF nets without dimensionality reduction are established. Finally, the results of simulations concerning multidimensional density estimation are briefly reported.

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Chennamma, H. R., and Lalitha Rangarajan. "Source Camera Identification Based on Sensor Readout Noise." International Journal of Digital Crime and Forensics 2, no. 3 (July 2010): 28–42. http://dx.doi.org/10.4018/jdcf.2010070103.

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A digitally developed image is a viewable image (TIFF/JPG) produced by a camera’s sensor data (raw image) using computer software tools. Such images might use different colour space, demosaicing algorithms or by different post processing parameter settings which are not the one coded in the source camera. In this regard, the most reliable method of source camera identification is linking the given image with the sensor of camera. In this paper, the authors propose a novel approach for camera identification based on sensor’s readout noise. Readout noise is an important intrinsic characteristic of a digital imaging sensor (CCD or CMOS) and it cannot be removed. This paper quantitatively measures readout noise of the sensor from an image using the mean-standard deviation plot, while in order to evaluate the performance of the proposed approach, the authors tested against the images captured at two different exposure levels. Results show datasets containing 1200 images acquired from six different cameras of three different brands. The success of proposed method is corroborated through experiments.

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Abbasi, Reza, Xinyue Hu, Alain Zhang, Isabelle Dummer, and Sebastian Wachsmann-Hogiu. "Optical Image Sensors for Smart Analytical Chemiluminescence Biosensors." Bioengineering 11, no. 9 (September 12, 2024): 912. http://dx.doi.org/10.3390/bioengineering11090912.

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Optical biosensors have emerged as a powerful tool in analytical biochemistry, offering high sensitivity and specificity in the detection of various biomolecules. This article explores the advancements in the integration of optical biosensors with microfluidic technologies, creating lab-on-a-chip (LOC) platforms that enable rapid, efficient, and miniaturized analysis at the point of need. These LOC platforms leverage optical phenomena such as chemiluminescence and electrochemiluminescence to achieve real-time detection and quantification of analytes, making them ideal for applications in medical diagnostics, environmental monitoring, and food safety. Various optical detectors used for detecting chemiluminescence are reviewed, including single-point detectors such as photomultiplier tubes (PMT) and avalanche photodiodes (APD), and pixelated detectors such as charge-coupled devices (CCD) and complementary metal–oxide–semiconductor (CMOS) sensors. A significant advancement discussed in this review is the integration of optical biosensors with pixelated image sensors, particularly CMOS image sensors. These sensors provide numerous advantages over traditional single-point detectors, including high-resolution imaging, spatially resolved measurements, and the ability to simultaneously detect multiple analytes. Their compact size, low power consumption, and cost-effectiveness further enhance their suitability for portable and point-of-care diagnostic devices. In the future, the integration of machine learning algorithms with these technologies promises to enhance data analysis and interpretation, driving the development of more sophisticated, efficient, and accessible diagnostic tools for diverse applications.

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Zhang, Yu, Guangyi Wang, and Jiangtao Xu. "Parameter Estimation of Signal-Dependent Random Noise in CMOS/CCD Image Sensor Based on Numerical Characteristic of Mixed Poisson Noise Samples." Sensors 18, no. 7 (July 13, 2018): 2276. http://dx.doi.org/10.3390/s18072276.

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Parameter estimation of Poisson-Gaussian signal-dependent random noise in the complementary metal-oxide semiconductor/charge-coupled device image sensor is a significant step in eliminating noise. The existing estimation algorithms, which are based on finding homogeneous regions, acquire the pair of the variances of noise and the intensities of every homogeneous region to fit the linear or piecewise linear curve and ascertain the noise parameters accordingly. In contrast to the existing algorithms, in this study, the Poisson noise samples of all homogeneous regions in every block image are pieced together to constitute a larger sample following the mixed Poisson noise distribution; then, the mean and variance of the mixed Poisson noise sample are deduced. Next, the mapping function among the noise parameters to be estimated—variance of Poisson-Gaussian noise and that of Gaussian noise corresponding to the stitched region in every block image—is constructed. Finally, the unbiased estimations of noise parameters are calculated from the mapping functions of all the image blocks. The experimental results confirm that the proposed method can obtain lower mean absolute error values of estimated noise parameters than the conventional ones.

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Gregorat, Leonardo, Marco Cautero, Alessandro Pitanti, Leonardo Vicarelli, Monica La Mura, Alvise Bagolini, Rudi Sergo, Sergio Carrato, and Giuseppe Cautero. "FPGA Readout for Frequency-Multiplexed Array of Micromechanical Resonators for Sub-Terahertz Imaging." Sensors 24, no. 22 (November 14, 2024): 7276. http://dx.doi.org/10.3390/s24227276.

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Field programmable gate arrays (FPGAs) have not only enhanced traditional sensing methods, such as pixel detection (CCD and CMOS), but also enabled the development of innovative approaches with significant potential for particle detection. This is particularly relevant in terahertz (THz) ray detection, where microbolometer-based focal plane arrays (FPAs) using microelectromechanical (MEMS) resonators are among the most promising solutions. Designing high-performance, high-pixel-density sensors is challenging without FPGAs, which are crucial for deterministic parallel processing, fast ADC/DAC control, and handling large data throughput. This paper presents a MEMS-resonator detector, fully managed via an FPGA, capable of controlling pixel excitation and tracking resonance-frequency shifts due to radiation using parallel digital lock-in amplifiers. The innovative FPGA architecture, based on a lock-in matrix, enhances the open-loop readout technique by a factor of 32. Measurements were performed on a frequency-multiplexed, 256-pixel sensor designed for imaging applications.

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Yeh, Wei Ming. "The Study of New Trend for DSC Scene Effects Technology." Advanced Materials Research 225-226 (April 2011): 1284–87. http://dx.doi.org/10.4028/www.scientific.net/amr.225-226.1284.

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Since early 2007, many ambitious DSC manufactures in Japan have paid special attention for built in digital effects, in order to create better quality of picture, such as: Face Detection, Smile Shutter Mode, Full frame CCD, Anti Shake system, Live View, CMOS sensor..., which were highly appreciated by many photo fans around the world, and created hot-selling record on favorite model. In fact, these fancy “Digital Technologies” could be standardized in selected new cameras right now. In late 2009, new artificial intelligence image chips such as: back-illuminated CMOS image sensor, 30x Optical Zoom (or more), Full HD Video, Sweep Panorama, Interchangeable Unit Camera System,Super High Speed ISO, Super Steady, Motion Remover.., have been promoted in new generation of camera. It could change not only the performance of new camera (DSC/DC) but to challenge the current DV market seriously, and may inspire new record-high selling again. In our experiment, we collect more than 300 cases from the telephone survey during Sep, 2010 and Dec, 2010. Total of 220 cases comply with the conditions. To probe mainly into the relationship between new generation DC Confidence level and 3 potential customers: Amateur Photographer (AP), Senior Photographer (SP), and college student (CS). That is the reason what we are probe into this highly competitively market with brilliant creative design, and hope to offer an objective suggestion for both industry and education administers.

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Siegel, Moritz, Lukas Traxler, and Laurin Ginner. "Robustness of Fourier Ptychographic Imaging to Variation of System Parameters." Electronic Imaging 2021, no. 15 (January 18, 2021): 166–1. http://dx.doi.org/10.2352/issn.2470-1173.2021.15.coimg-166.

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In most optic systems images are captured using a CCD/CMOS sensor, where the phases of the converted photons are inevitably lost. Fourier Ptychographic Microscopy (FPM) circumvents this issue by capturing normal microscopy images, and Fourier transforming them computationally (hence the name). Reconstructing the complex object not only yields amplitude but also phase information, enhanced up to super-resolution. Yet one disadvantage remains unsolved: FPM is a very ill-posed problem, the algorithm is not guaranteed to converge to the correct solution, if it converges at all. In practice this means that there is reasonable doubt if the recovered image actually represents the object under the microscope. This work inquires the quality of FPM reconstruction under variation of important system parameters in simulation and experiment. It shows that the alignment of the illumination source is quite critical: even 0.2 degrees off renders reconstruction useless. This paper thus furthers the costbenefit analysis of which amount of computation time should be spent on digital post-correction.

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Konyakhin, Igor A., Alexander N. Timofeev, and Sergey N. Yaryshev. "High Precision Angular and Linear Measurements Using Universal Opto-Electronic Measuring Modules in Distributed Measuring Systems." Key Engineering Materials 437 (May 2010): 160–64. http://dx.doi.org/10.4028/www.scientific.net/kem.437.160.

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Large or long objects require measuring systems as a combination of more than one measuring instrument. In this case, the combination of instruments consists of one central module and several measuring modules. The measuring modules make the preliminary computation of measuring information and translate it to the central module for final computation of measuring parameters. The central module also makes statistics of measuring and archive information. Some tasks require noncontact measurement of angular and linear coordinates of objects or places. The optoelectronic measuring devices (OEMD) are ideal for these purposes. These devices also have other advantages such as high precision and adaptability. One and two coordinates high precision modules based on matrix and linear CCD or CMOS photo sensors are described. In this article variants of the distributed measuring systems are described. The basic attention is given to the description of the unified optoelectronic modules for measurement of angular and linear coordinates. Basic parameters and application examples of measuring modules are presented.

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Bolatbek, Zhanibek, and Imad Agha. "Toward Single-Shot Real-Time Spectroscopy of Dynamic Materials via White-Light and Supercontinuum Light Sources." Photonics 11, no. 12 (November 26, 2024): 1119. http://dx.doi.org/10.3390/photonics11121119.

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In conventional camera or monochromator-based spectroscopy, different wavelengths, spanning from short ultraviolet region to long infrared region, are calculated under steady-state conditions due to the temporally multiplexed nature of conventional CMOS/CCD-equipped spectrometers, which limit the refresh rates to the order of milliseconds for most tools available on the market. These refresh rates might not be suitable for most temporally dynamic effects that govern the behavior of disparate effects, such as phase transition in phase-change materials, conformal changes in molecules, and microbial community evolution, among others. Pump-probe methods are often presented as a solution to the capture speed limitation, but in themselves are not applicable universally and are not truly “real-time”. In this work, we present an evolution to the conventional spectrometers, increasing its speed by over 4 orders of magnitude while maintaining reasonable spectral resolution. We additionally present a path that combines our technique with supercontinuum light sources for even more ambitious future applications.

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Lu, Wang, and JiangYuan Hou. "Intelligent Recognition Method of Athlete Wrong Movement Based on Image Vision." Scientific Programming 2021 (November 12, 2021): 1–11. http://dx.doi.org/10.1155/2021/8467906.

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Current methods of human body movement recognition neglect the depth denoising and edge restoration of movement image, which leads to great error in athletes’ wrong movement recognition and poor application intelligence. Therefore, an intelligent recognition method based on image vision for sports athletes’ wrong actions is proposed. The basic principle, structure, and 3D application of computer image vision technology are defined. Capturing the human body image and point cloud data, the three-dimensional dynamic model of sports athletes action is constructed. The color camera including CCD sensor and CMOS sensor is selected to collect the wrong movement image of athlete and provide image data for the recognition of wrong movement. Wavelet transform coefficient and quantization matrix threshold are introduced to denoise the wrong motion images of athletes. Based on this, the feature of sports athlete’s motion contour image is extracted in spatial frequency domain, and the edge of the image is further recovered by Canny operator. Experimental results show that the proposed method can accurately identify the wrong movements of athletes, and there is no redundancy in the recognition results. Image denoising effect is good and less time-consuming and can provide a reliable basis for related fields.

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Journal articles on the topic 'CCD-On-CMOS'

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