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Optical memory integrates the function of optical sensing in memory devices, remarkably promoting the interconnection between sensory and memory terminals. Silicon charge-coupled photodetectors and floating gate memory have been widely used in imaging and storage technologies, respectively. However, the heterogeneous integration of the two devices requires technological innovation and complex electrical connections. In this work, we adopt a three-dimensional layer stacking method to design a novel optical memory device. On the top of Si charge-coupled photodetectors, we successively deposit two-dimensional graphene, hexagonal boron nitride, and molybdenum disulfide as a floating gate layer, a tunneling layer, and a readout layer, respectively. By applying a gate bias on lightly doped Si, a deep depletion layer is formed with a high voltage potential drop. Under dark conditions, the depletion layer cannot be filled, and the electric field across the h-BN tunnel barrier is relatively small. Under light irradiation, the deep depletion layer is gradually filled, and the h-BN tunneling layer withstands the increasing electric field, resulting in charge storage in the floating gate layer. Based on this mechanism, the device exhibits a gate voltage-dependent operation mode, including an integrated optical sensing-memory mode and an electrically driven storage mode. Under moderate gate voltage, the device can effectively detect the optical information with varied intensity and store the optical information in the floating gate, displaying optically controlled memory characteristics. Our work demonstrates a compact device structure for optical memory and displays excellent optically controlled memory performance, which can be applied in artificial vision systems. [ABSTRACT FROM AUTHOR]

Spatial heterodyne Raman spectrometers (SHRSs) are modified forms of Michelson interferometers, except the mirrors in a Michelson interferometer are replaced with stationary diffraction gratings. This design removes the need for an entrance slit, as is the case in a dispersive spectrometer, and removes the need to scan the spectrum by using a moving mirror in a modern Michelson interferometer. In previous studies, various SHRS variants, such as free-standing two-grating SHRS, single-grating SHRS (1g-SHRS), monolithic SHRS (mSHRS), and single-grating mSHRS (1g-mSHRS), have been evaluated. However, the present study exclusively focuses on the 1g-mSHRS configuration. The 1g-mSHRS and 1g-SHRS increase the spectral range at fixed grating line density while trading off spectral resolution and resolving power. The mSHRS benefits from increased rigidity, lack of moving parts, and reduced footprint. In this study, we investigate how the choice of detector impacts the performance of the 1g-mSHRS system, with a specific focus on evaluating the performance of three types of cameras: charged-coupled device (CCD), intensified CCD (ICCD), and complementary metal–oxide–semiconductor (CMOS) cameras. These systems were evaluated using geological, organic, and inorganic samples using a 532 nm continuous wave laser for the CMOS and CCD cameras, and a 532 nm neodymium-doped yttrium aluminum garnet pulsed laser for the ICCD camera. The footprint of the 1g-mSHRS was 3.5 × 3.5 × 2.5 cm3 with a mass of 272 g or 80 g, depending on whether the monolith housing is included or not. We found that increasing the number of pixels utilized along the x -axis of the camera increases fringe visibility (FV) and optimizes the resolution (by capturing the entirety of the grating and magnifying the fringes). The number of pixels utilized in the y -axis, chip size, and dimensions, affect the signal-to-noise ratio of the systems. Additionally, we discuss the effect of pixel pitch on the recovery of Fizeau fringes, including the relationship between the Nyquist frequency, aliasing, and FV. Graphical abstract This is a visual representation of the abstract. [ABSTRACT FROM AUTHOR]

In this work we demonstrate an advanced concept of a charge-shifting charge-coupled device (CCD) read-out combined with shifted excitation Raman difference spectroscopy (SERDS) capable of operating at up to 10 kHz acquisition rates for the effective mitigation of fast-evolving interfering backgrounds in Raman spectroscopy. This rate is 10-fold faster than that achievable with an instrument we described previously and is overall 1000-fold faster than possible with conventional spectroscopic CCDs capable of operating at up to ∼10 Hz rates. The speed enhancement was realized by incorporating a periodic mask at the internal slit of an imaging spectrometer permitting a smaller shift of the charge on the CCD (8 pixels) to be required during the cyclic shifting process compared with the earlier design which employed an 80-pixel shift. The higher acquisition speed enables the more accurate sampling of the two SERDS spectral channels, enabling it to effectively tackle highly challenging situations with rapidly evolving interfering fluorescence backgrounds. The performance of the instrument is evaluated for heterogeneous fluorescent samples which are moved rapidly in front of the detection system aiming at the differentiation of chemical species and their quantification. The performance of the system is compared with that of the earlier 1 kHz design and a conventional CCD operated at its maximum rate of 5.4 Hz as previously. In all situations tested, the newly developed 10 kHz system outperformed the earlier variants. The 10 kHz instrument can benefit a number of prospective applications including: disease diagnosis where high sensitivity mapping of complex biological matrices in the presence of natural fluorescence bleaching restricts achievable limits of detection; accurate data acquisition from moving heterogeneous samples (or moving a handheld instrument in front of the sample during data acquisition) or data acquisition under varying ambient light conditions (e.g., due to casting shadows, sample or instrument movement). Other beneficial scenarios include monitoring rapidly evolving Raman signals in the presence of largely static background signals such as in situations where a heterogeneous sample is moving rapidly in front of a detection system (e.g., a conveyor belt) in the presence of static ambient light. Graphical Abstract This is a visual representation of the abstract. [ABSTRACT FROM AUTHOR]

Creutzfeldt-Jakob disease is a fatal transmissible prion disease of the central nervous system. Dizziness as an initial manifestation of Creutzfeldt-Jakob disease is rare. However, patients with Creutzfeldt-Jakob disease and dizziness may initially visit the otolaryngology department, but this is uncommon. We report the case of a 56-year-old woman with Creutzfeldt-Jakob disease who initially presented with dizziness as an emergency patient to the otolaryngology department. Primary position upbeat nystagmus was identified using a charge-coupled device camera with infrared illumination. Electronystagmography revealed impaired smooth pursuit and diminished optokinetic nystagmus. Based on these findings, we immediately suspected an intracranial cause of dizziness and reached a presumptive diagnosis of sporadic Creutzfeldt-Jakob disease, thus preventing severe transmission. This case emphasizes that Creutzfeldt-Jakob disease should be included as a differential diagnosis for patients with dizziness and abnormal eye movements, such as primary position upbeat nystagmus, which might be caused by intracranial disease. [ABSTRACT FROM AUTHOR]

In order to investigate the effect of temperature on proton radiation in the charge-coupled device (CCD), charge transfer efficiency (CTE) and dark current are tested at different temperatures on interline transfer CCD irradiated with protons. The aim of this paper is to analyze the characteristics of the defects introduced by proton irradiation in CCD and describe the mechanism of temperature effect on sensitive parameters of proton radiation effect in CCD. For the increasing temperature of −50°C ∼40°C, CTE begins with a decrease, followed by a minimum of 0°C, and ends with an increase; dark current (DC) increases significantly with the increasing temperature. By combining these results, a conclusion is made that temperature will affect the effect of defect introduced by proton, including the effect of the defect on the carrier mobility and lifetime, so as to affect the performance parameters of CCD. [ABSTRACT FROM AUTHOR]

This paper describes the design and simulation of a radiation detector system for diagnostic measurements of photon beams produced by Thomson or Compton Scattering. The photon beam is Compton scattered in a thin passive converter, and the resulting electrons are analyzed using a charge-coupled device-based tracker and classification algorithms. The flux of the scattered electrons is much lower than that of the photon beam and is additionally dispersed. This dispersal enables measurements while avoiding pileup, which is important in order to provide diagnostic information from intense 'shot’ based pulsed systems, such as those being built to leverage laser wakefield accelerators. Simulations indicate that the designed system is capable of resolving beam parameters from a single shot. The fidelity to which various beam parameters can be resolved is presented as are methods that could result in further improvement to diagnostic resolution.

This paper presents an investigation of the responsivity of a time-delay integration (TDI) charge-coupled device that employs anti-blooming clocking and uses a varying number of TDI stages. The influence of charge blooming caused by unused TDI stages in a TDI deployed selection scheme is shown experimentally, and an anti-blooming clocking mechanism is analyzed. The impact of blooming on sensor characteristics, such as the responsivity, the conversion gain, and the signal-to-noise ratio, is investigated. A comparison of the measurements with and without this anti-blooming clocking mechanism is presented and discussed in detail. [ABSTRACT FROM AUTHOR]

This article reviews nearly 60 years of solid-state image sensor evolution and identifies potential new frontiers in the field. From early work in the 1960s, through the development of charge-coupled device image sensors, to the complementary metal oxide semiconductor image sensors now ubiquitous in our lives, we discuss highlights in the evolutionary chain. New frontiers, such as 3D stacked technology, photon-counting technology, and others, are briefly discussed.

Mie Scattering Light Detection and Ranging (Mie-Lidar) is the most frequently used tool for obtaining the vertical profile of aerosol extinction coefficients. However, Mie-Lidar has an area that is not fully overlapping (called a transition zone) several hundred meters above the ground. There is uncertainty, although a geometric overlap factor (GOF) correction is normally used. To specifically evaluate the error of Mie-Lidar in the transition zone, a dual charge-coupled device (CCD) laser system (DCLS) is developed in this study. Multiple joint measurements as well as a continuous detection experiment are conducted. The extinction coefficient profiles obtained with the DCLS and Mie-Lidar are compared. The results indicate that the extinction coefficients are nearly consistent above the transition zone, and Pearson’s correlation coefficient remains above 0.9. However, the extinction coefficients have specific differences in the transition zone, and the linear fit results are relatively bad. The average relative difference of the extinction coefficients between the Mie-Lidar and DCLS is nearly 20%. Compared Mie-Lidar, the blind zone of the DCLS is merely approximately 8 m. The DCLS shows more details of the near-surface atmosphere, and its spatial resolution of up to 1 × 10–3 m can provide a useful reference for Mie-Lidar. The DCLS contributes to obtaining a more accurate vertical distribution of aerosols in the atmospheric boundary layer.

This paper presents an investigation of the responsivity of a time-delay integration (TDI) charge-coupled device that employs anti-blooming clocking and uses a varying number of TDI stages. The influence of charge blooming caused by unused TDI stages in a TDI deployed selection scheme is shown experimentally, and an anti-blooming clocking mechanism is analyzed. The impact of blooming on sensor characteristics, such as the responsivity, the conversion gain, and the signal-to-noise ratio, is investigated. A comparison of the measurements with and without this anti-blooming clocking mechanism is presented and discussed in detail.

Gene transcription is regulated in response to environmental changes and developmental cues. In mammalian cells subjected to stress conditions such as heat shock, transcription of most protein-coding genes decreases, while the transcription of heat shock protein genes increases. Repression involves direct binding to RNA polymerase II (Pol II) of certain noncoding RNAs (ncRNAs) that are upregulated upon heat shock. Another class of ncRNAs is also upregulated and binds to Pol II but does not inhibit transcription. Incorporation of repressive ncRNAs into pre-initiation complexes prevents transcription initiation, while non-repressive ncRNAs are displaced from Pol II by TFIIF. Here, we present cryo-electron microscopy reconstructions of human Pol II in complex with six different ncRNAs from mouse and human. Our structures show that both repressive and non-repressive ncRNAs bind to a conserved binding site within the cleft of Pol II. The site, which is also shared with a previously characterized yeast aptamer, is close to the active center and, thus, in an ideal position to regulate transcription. Importantly, additional RNA elements extend flexibly beyond the docking site. We propose that the differences concerning the repressive activity of the ncRNAs analyzed must be due to the distinct character of these more unstructured, flexible segments of the RNA that emanate from the cleft.

The lab spectroscopy using Vis/SWNIR and NIR spectrometers was used to estimate the major fertility parameters in calcareous topsoil from arid region of central Iran. The fertility parameters included soil organic matter (SOM), total nitrogen (TN), available phosphorus (P -avl), and available potassium (K -avl). A total of 151 samples were collected from the depth of 0–20 cm, and the diffuse reflectance spectra of them were collected using charge-coupled device (CCD) and indium-gallium-arsenide (InGaAs) spectrometers. To extract the prediction models, partial least squares (PLS) as linear, and artificial neural networks (ANN) and support vector machines (SVM) as nonlinear multivariate techniques were used. The CCD-based spectra combined with the ANN model led to excellent predictability for SOM (residual predictive deviation (RPD) = 2.60), TN (RPD = 2.54), and P -avl (RPD = 3.01) and very good prediction for K -avl (RPD = 2.02). However, the InGaAs-based spectrometer outperformed the CCD one for predicting all the soil fertility parameters. The best prediction models were obtained from the nonlinear multivariate techniques where the excellent predictions were provided by the ANN model for SOM (R 2 p = 0.941; RPD = 3.27), P -avl (R 2 p = 0.902; RPD = 3.34), and K -avl (R 2 p = 0.863; RPD = 2.69) and by SVM for TN (R 2 p = 0.863; RPD = 2.91). This study revealed that despite the great potential of InGaAs spectrometers for predicting the soil fertility parameters, the low-cost CCD-based spectrometer could result in satisfactory performance when the appropriate nonlinear technique is used for data analysis. • The potential of two spectrometers was compared to estimate fertility parameters. • Linear and nonlinear techniques were used to extract the prediction models. • CCD spectrometer combined with the ANN model led to satisfactory performance. • Nonlinear multivariate techniques resulted in the best accuracy. [ABSTRACT FROM AUTHOR]

As it isn't sufficient to inspect the scene in several applications to think about just the noticeable articles, route and object identification require distinctive imaging modalities. In this paper, we propose another picture combination technique dependent on saliency discovery and two-scale picture disintegration. This technique is gainful on the grounds that saliency-based strategies have been broadly utilized in the combination of infrared (IR) and visible (VIS) images, which can feature the notable article locale and save the point by point foundation data at the same time. Another weight map development process dependent on visual saliency is proposed. Thus, it is quick, proficient and skilful. Our strategy is evaluated on a few datasets and is assessed subjectively by visual examination and quantitatively utilizing metrics. Results that are achieved by Matlab-2019A version through the comparison of entropy, standard deviation, PSNR and SSIM values of VIS and IR image datasets of several fusion methodologies uncover that the proposed technique execution is practically identical or better than the current strategies. [ABSTRACT FROM AUTHOR]

The existence of foreign objects in crystal-clear water in beverage industries may cause major safety and health issues. The current observation of solid contamination such as X-ray and metal detector involves hazardous radiation. Some of the sensors applied intrusive and invasive techniques. This may cause the instability of the process flow. Therefore, this paper aims to develop a noninvasive and nonintrusive charge-coupled device optical tomography (CCD OPT) system to detect solid contamination in crystal-clear water. Investigations on three different opacity levels of objects, opaque, translucent, and transparent, are involved. The first experiment investigates the velocity and acceleration of the free-falling object. It is conducted to validate the accuracy of the system to detect the appearance of foreign object. The experiment result indicated that the system reached 82% accuracy. The second experiment reconstructs cross-sectional image of the process flow. The image reconstruction results are analyzed using the area error (AE) method. The image reconstruction AE range is between 0.0372 and 0.7269. The AE results show that the system has the capability to detect different opacity of objects which exist in crystal-clear water. Both experiments prove that the CCD OPT system is able to detect solid contamination in crystal-clear water. [ABSTRACT FROM AUTHOR]

The photostimulable phosphor (PSP) plate and charge‐coupled device (CCD) are receptors commonly used for intraoral radiography in U.S. dental schools. However, it is unclear which receptor is more beneficial for radiology education and patient care in an academic setting. The aim of this study was to compare the time efficiency, image quality, and operator performance for student‐operated PSP plate and CCD receptors. At one U.S. dental school in 2018, 20 dental hygiene and dental students (n=10 each) were recruited as operators. They each exposed anterior and posterior periapical and bitewing radiographs on dental radiograph teaching and training replica using the PSP plate and CCD as receptors. The time taken to expose the radiographs was recorded. Image sharpness/definition, brightness/contrast, and technical errors, including placement, angulation, and cone cut errors, were evaluated on a three‐point scale with 0=non‐diagnostic, 1=diagnostic acceptable with minor errors, and 2=perfect diagnostic quality. The results showed that it was generally faster for the students to expose intraoral radiographs with CCDs than with PSP plates, although the difference was not significant (p>0.05). Image quality and technical accuracy, especially angulation, were significantly superior for PSP relative to CCD (p<0.05). This study found that PSP imaging was of higher quality and accuracy than CCD, whereas CCD was more efficient. Dental and dental hygiene students would benefit from being trained on both receptors to be able to adapt to a diversified workplace. [ABSTRACT FROM AUTHOR]

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The prerequisite of gate oxide local thinning (OLT) effect for subthreshold swing (SS) reduction to sub-60 mV/decade on charge-coupled metal–insulator–semiconductor (MIS) tunnel transistor is specified in this paper. The OLT process is employed by positive voltage stress, which is regarded as an efficient method to create a soft breakdown of oxides. The gate OLT process dramatically reduces the SS of the device, for instance, from the minimum SS of 79.31 to 9.7 mV/decade. Meanwhile, average SS of 28.22 mV/decade for over two current decades is acquired after the gate OLT process. The enhanced efficiency for minority carrier supply under gate oxide is responsible for the amelioration. The physical mechanism is proposed as the OLT spot-induced energy lateral transport and reduction of the energy barrier for minority carrier supply. The mechanism is then clarified by 2-D TCAD simulation. The extremely low SS and its physical insights of gate OLT effect on charge-coupled MIS tunnel transistor are believed beneficial for future developments on low-SS-related devices. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Remote Sensing is the property of Editorial Office of Journal of Remote Sensing & Science Publishing Co. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Charge-coupled devices (CCDs) show potential for detecting charged particles and ionizing radiation. In particular, the clusters in the pixel images produced can be distinctive for α and β radiation, with α particles causing symmetrical clusters or vertical tracks, and β particles causing long, curved tracks. This distinction may be exploited by means of a handheld, portable device for in-situ detection, and identification of radioactive contamination. β-particle track interactions in CCDs have been investigated. Simulative results using CASINO (Monte Carlo Simulation of Electron Trajectory in Solids) attempt to predict the size of β-particle pixel clusters, using 512 keV and 310 keV electrons to represent 137Cs and 60Co, respectively. The number of pixels that higher-energy electrons traversed peaked at two, while lower-energy electrons had a smaller peak of 2.5 pixels, with a higher proportion of large cluster sizes. This finding is consistent with the higher scattering cross-section for lower-energy β particles. By contrast, experimental data show a peak at one pixel for both sources, owing to the addition of smaller γ clusters. The 60Co source shows a higher proportion of large cluster sizes than the 137Cs, as was also seen in the simulation; however, the difference was small, as these sources are similar in energy. Simulative and experimental data will be used to process the CCD images further, with the objective of distinguishing between β and γ radiation. Investigations have also been carried out using a 210Po α particle source. Horizontal streaks were seen in the images produced, with an average length of 14 pixels. Further research will be performed using an accelerator to obtain different α-particle energies. [ABSTRACT FROM AUTHOR]

Optical tomography (OPT) is a method to capture a cross-sectional image based on the data obtained by sensors, distributed around the periphery of the analyzed system. This system is based on the measurement of the final light attenuation or absorption of radiation after crossing the measured objects. The number of sensor views will affect the results of image reconstruction, where the high number of sensor views per projection will give a high image quality. This research presents an application of charge-coupled device linear sensor and laser diode in an OPT system. Experiments in detecting solid and transparent objects in crystal clear water were conducted. Two numbers of sensors views, 160 and 320 views are evaluated in this research in reconstructing the images. The image reconstruction algorithms used were filtered images of linear back projection algorithms. Analysis on comparing the simulation and experiments image results shows that, with 320 image views giving less area error than 160 views. This suggests that high image view resulted in the high resolution of image reconstruction. [ABSTRACT FROM PUBLISHER]

A new mathematical model is proposed for the capacitance of the pinned photodiode (PPD) taking into account the potential changes at the PPD center. Aside from the electric field and the depletion region that is created by the p-n junctions, a depletion process occurs at the center of PPD. In this letter, the total capacitance of PPD is demonstrated to be composed of two series capacitances; the junction capacitance around the PPD and the inner capacitance at the PPD center. For the junction capacitance calculation, a previously developed model can be utilized. On the other hand, the inner capacitance is a result of the depletion at the PPD center, which is modeled in this letter. Both capacitances are voltage-dependent and the total series capacitance fits to the measurement data. [ABSTRACT FROM PUBLISHER]

High purity titanium and titanium alloy have good plasticity, but with the presence of impurity, their performance will become brittle and hard. The accurate quantitative analysis of impurity elements is useful for carrying on the quality control of titanium products. For analysis of impurity elements, in the current national standard method, DC Arc was used as an excitation source with a higher evaporation temperature, the spectrograph process includes developing, fixing, blackness measurement and other steps, the procedure is too complicated and tedious with large measurement error. In this paper, DC Arc Atomic Emission Spectrometer (wavelength range of 200-800 nm) equipped with echelle grating and charge-coupled detector (CCD) is applied, the spectral lines interference analysis and spectral intensity measurement can be conducted at the same time, and the instrument provides more spectral information. Based on this, a rapid analysis method for 10 trace elements (Mn, Sn, Cr, Ni, Al, Mo, V, Cu, Zr, Y) in titanium and titanium alloy was been established. In the process of experiments, four types of spectral interference from titanium matrix, added chemical component elements, iron and impurity elements were studied, and the appropriate analytical were determined. Meanwhile, through application of a kind of shallow, thin and narrow cup-shaped electrode as working electrode, evaporation of sample was improved. With a mixture of AgCl and carbon powder used as buffer, the spectral line intensity of the measured elements was increased. The detection range of the method is 0.001%-0.06%, the precision is less than 15%, the recoveries are 90.0%-110.0%. The method is suitable for simultaneous determination of impurity elements in large quantities of titanium and titanium alloy samples.

Charge-coupled device (CCD) spectrometers are widely used as detectors in analytical laboratory instruments and as sensors for in situ optical measurements. However, as the applications become more complex, the physical and electronic limits of the CCD spectrometers may restrict their applicability. The errors due to dark currents, temperature variations, and blooming can be readily corrected. However, a correction for uncertainty of integration time and wavelength calibration is typically lacking in most devices, and detector non-linearity may distort the signal by up to 5% for some measurements. Here, we propose a simple correction method to compensate for non-linearity errors in optical measurements where compact CCD spectrometers are used. The results indicate that the error due to the non-linearity of a spectrometer can be reduced from several hundred counts to about 40 counts if the proposed correction function is applied.