Scientific CMOS Camera Research Articles

Wide-Field Planar Magnetic Imaging Using Spins in Diamond

The nitrogen-vacancy color centers in diamond can be used as an excellent magnetic sensor. In this work, we present a wide-field planar magnetic imaging technique based on nitrogen-vacancy color centers. Through optically detected magnetic resonance (ODMR) which is readout from a scientific CMOS camera to extract resonance frequency, we experimentally reconstruct the magnetic field distribution of permanent magnets and particles of magnetite (Fe3O4). Moreover, by using this method we imagined the magnetic field distribution of one integrated cell heater widely used in temperature control with magnetic field suppression. And the experiment shows that this technique can be applied in engineering. The imaging field of this technology can reach the sub-millimeter level and the spatial resolution can reach the optical diffraction limit. The presented wide-field NV imaging technique offers wide-field imaging, high spatial resolution, and high magnetic sensitivity.

Focus on lasers, imaging, and microscopy

Focus on lasers, imaging, and microscopy

Fast High-Energy X-Ray Imaging for Severe Accidents Experiments on the Future PLINIUS-2 Platform

The future PLINIUS-2 platform of the Commissariat a l’Energie Atomique (CEA) of Cadarache will be dedicated to the study of corium interactions in severe nuclear accidents, and will host innovative large-scale experiments. The nuclear measurement laboratory of CEA Cadarache is in charge of real-time high-energy X-ray imaging setups, for the study of the corium–water and corium–sodium interaction, and of the corium stratification process. Imaging such large and high-density objects requires a 15 MeV linear electron accelerator coupled to a tungsten target creating a high-energy bremsstrahlung X-ray flux, with corresponding dose rate about 100 Gy/min at 1 m. The signal is detected by phosphor screens coupled to high-framerate scientific CMOS cameras. The imaging setup is established using an experimentally validated home-made simulation software High-Energy MODeling for RAdiography and TOmography (MODHERATO). The code computes quantitative radiographic signals from the description of the source, object geometry and composition, detector, and geometrical configuration (magnification factor, etc.). It accounts for several noise sources (photonic and electronic noises, and swank and readout noise), and for image blur due to the source spot-size and to the detector unsharpness. In a view to PLINIUS-2, the simulation has been improved to account for the scattered flux, which is expected to be significant. This paper presents the scattered flux calculation using the Monte-Carlo N-particle transport code, and its integration into the MODHERATO simulation. Then, the validation of the improved simulation is presented, through confrontation to real measurement images taken on a small-scale equivalent setup on the PLINIUS platform. Excellent agreement is achieved. This improved simulation is therefore being used to design the PLINIUS-2 imaging setups (source, detectors, and cameras). Simulation will be presented for different configurations, as well as preliminary tests of alternative detectors considered for PLINIUS-2.

Lightweight sCMOS-based high-density diffuse optical tomography.

.Though optical imaging of human brain function is gaining momentum, widespread adoption is restricted in part by a tradeoff among cap wearability, field of view, and resolution. To increase coverage while maintaining functional magnetic resonance imaging (fMRI)-comparable image quality, optical systems require more fibers. However, these modifications drastically reduce the wearability of the imaging cap. The primary obstacle to optimizing wearability is cap weight, which is largely determined by fiber diameter. Smaller fibers collect less light and lead to challenges in obtaining adequate signal-to-noise ratio. Here, we report on a design that leverages the exquisite sensitivity of scientific CMOS cameras to use fibers with smaller cross-sectional area than current high-density diffuse optical tomography (HD-DOT) systems. This superpixel sCMOS DOT (SP-DOT) system uses -diameter fibers that facilitate a lightweight, wearable cap. We developed a superpixel algorithm with pixel binning and electronic noise subtraction to provide high dynamic range (), high frame rate (), and a low effective detectivity threshold (), each comparable with previous HD-DOT systems. To assess system performance, we present retinotopic mapping of the visual cortex ( subjects). SP-DOT offers a practical solution to providing a wearable, large field-of-view, and high-resolution optical neuroimaging system.

Multiplane and Spectrally-Resolved Single Molecule Localization Microscopy with Industrial Grade CMOS cameras

This work explores the use of industrial grade CMOS cameras for single molecule localization microscopy (SMLM). We show that industrial grade CMOS cameras approach the performance of scientific grade CMOS cameras at a fraction of the cost. This makes it more economically feasible to construct high-performance imaging systems with multiple cameras that are capable of a diversity of applications. In particular we demonstrate the use of industrial CMOS cameras for biplane, multiplane and spectrally resolved SMLM. We also provide open-source software for simultaneous control of multiple CMOS cameras and for the reduction of the movies that are acquired to super-resolution images.

Fast high-energy X-ray imaging for Severe Accidents experiments on the future PLINIUS-2 platform

The future PLINIUS-2 platform of CEA Cadarache will be dedicated to the study of corium interactions in severe nuclear accidents, and will host innovative large-scale experiments. The Nuclear Measurement Laboratory of CEA Cadarache is in charge of real-time high-energy X-ray imaging set-ups, for the study of the corium-water and corium-sodium interaction, and of the corium stratification process. Imaging such large and high-density objects requires a 15 MeV linear electron accelerator coupled to a tungsten target creating a high-energy Bremsstrahlung X-ray flux, with corresponding dose rate about 100 Gy/min at 1 m. The signal is detected by phosphor screens coupled to high-framerate scientific CMOS cameras. The imaging set-up is established using an experimentally-validated home-made simulation software (MODHERATO). The code computes quantitative radiographic signals from the description of the source, object geometry and composition, detector, and geometrical configuration (magnification factor, etc.). It accounts for several noise sources (photonic and electronic noises, swank and readout noise), and for image blur due to the source spot-size and to the detector unsharpness. In a view to PLINIUS-2, the simulation has been improved to account for the scattered flux, which is expected to be significant. The paper presents the scattered flux calculation using the MCNP transport code, and its integration into the MODHERATO simulation. Then the validation of the improved simulation is presented, through confrontation to real measurement images taken on a small-scale equivalent set-up on the PLINIUS platform. Excellent agreement is achieved. This improved simulation is therefore being used to design the PLINIUS-2 imaging set-ups (source, detectors, cameras, etc.).

Surface thermography using dual channel imaging based on the blue and red emission of Ba3MgSi2O8:Eu2+, Mn2+

In this investigation, we present a surface temperature determination method based on the luminescence characteristics of Ba3MgSi2O8:Eu2+, Mn2+. Simple optics utilizing only one RGB scientific CMOS camera makes this measurement technique easily applicable. Four different imaging methods were developed and are presented together with the corresponding calibration curves. We successfully utilized the methods to take a surface temperature distribution image on glass plates with a point heat source between them.

Wide-field spectrally resolved quantitative fluorescence imaging system: toward neurosurgical guidance in glioma resection.

In high-grade glioma surgery, tumor resection is often guided by intraoperative fluorescence imaging. 5-aminolevulinic acid-induced protoporphyrin IX (PpIX) provides fluorescent contrast between normal brain tissue and glioma tissue, thus achieving improved tumor delineation and prolonged patient survival compared with conventional white-light-guided resection. However, commercially available fluorescence imaging systems rely solely on visual assessment of fluorescence patterns by the surgeon, which makes the resection more subjective than necessary. We developed a wide-field spectrally resolved fluorescence imaging system utilizing a Generation II scientific CMOS camera and an improved computational model for the precise reconstruction of the PpIX concentration map. In our model, the tissue’s optical properties and illumination geometry, which distort the fluorescent emission spectra, are considered. We demonstrate that the CMOS-based system can detect low PpIX concentration at short camera exposure times, while providing high-pixel resolution wide-field images. We show that total variation regularization improves the contrast-to-noise ratio of the reconstructed quantitative concentration map by approximately twofold. Quantitative comparison between the estimated PpIX concentration and tumor histopathology was also investigated to further evaluate the system.

Developments on a SEM-based X-ray tomography system: Stabilization scheme and performance evaluation.

Recent improvements in a SEM-based X-ray tomography system are described. In this type of equipment, X-rays are generated through the interaction between a highly focused electron-beam and a geometrically confined anode target. Unwanted long-term drifts of the e-beam can lead to loss of X-ray flux or decrease of spatial resolution in images. To circumvent this issue, a closed-loop control using FFT-based image correlation is integrated to the acquisition routine, in order to provide an in-line drift correction. The X-ray detection system consists of a state-of-the-art scientific CMOS camera (indirect detection), featuring high quantum efficiency (∼60%) and low read-out noise (∼1.2 electrons). The system performance is evaluated in terms of resolution, detectability, and scanning times for applications covering three different scientific fields: microelectronics, technical textile, and material science.

Frequency modulation technique for wide-field imaging of magnetic field with nitrogen-vacancy ensembles

We report on the application of a frequency modulation technique to wide-field magnetic field imaging of nitrogen-vacancy centers in diamond at room temperature. We use a scientific CMOS (sCMOS) camera to collect photoluminescence images from a large number of nitrogen-vacancy center ensembles in parallel. This technique allows a significant reduction in the measurement time required to obtain a magnetic field image compared with a scanning probe approach at a comparable magnetic field sensitivity.

高动态科学级CMOS相机设计与成像分析

高动态科学级CMOS相机设计与成像分析

Ccoffinn: Automated Wave Tracking in Cultured Cardiac Monolayers

Cardiac arrhythmias are one of the most frequent causes of death worldwide. A popular biological model used to study arrhythmogenesis is the cultured cardiac cell monolayer, which provides a good trade-off between physiological relevance and experimental access. Excitation wave patterns are imaged using high-bandwidth detectors, producing large data sets that are typically analyzed manually. To make such analysis less time consuming and less subjective, we have designed and implemented a toolkit for segmentation and tracking of cardiac waves in optical mapping recordings. The toolkit is optimized for high-resolution detectors to accommodate the growing availability of inexpensive high-resolution detectors for life science imaging applications (e.g., scientific CMOS cameras). The software extracts key features of propagating waves, such as wavefront speed and entropy. The methods have been validated using synthetic data, and real-world examples are provided, showing a difference in conduction velocity between two different types of cardiac cell cultures.

Adaptive multiphoton endomicroscopy through a dynamically deformed multicore optical fiber using proximal detection.

This paper demonstrates multiphoton excited fluorescence imaging through a polarisation maintaining multicore fiber (PM-MCF) while the fiber is dynamically deformed using all-proximal detection. Single-shot proximal measurement of the relative optical path lengths of all the cores of the PM-MCF in double pass is achieved using a Mach-Zehnder interferometer read out by a scientific CMOS camera operating at 416 Hz. A non-linear least squares fitting procedure is then employed to determine the deformation-induced lateral shift of the excitation spot at the distal tip of the PM-MCF. An experimental validation of this approach is presented that compares the proximally measured deformation-induced lateral shift in focal spot position to an independent distally measured ground truth. The proximal measurement of deformation-induced shift in focal spot position is applied to correct for deformation-induced shifts in focal spot position during raster-scanning multiphoton excited fluorescence imaging.

4D x-ray phase contrast tomography for repeatable motion of biological samples.

X-ray phase contrast tomography based on a grating interferometer was applied to fast and dynamic measurements of biological samples. To achieve this, the scanning procedure in the tomographic scan was improved. A triangle-shaped voltage signal from a waveform generator to a Piezo stage was used for the fast phase stepping in the grating interferometer. In addition, an optical fiber coupled x-ray scientific CMOS camera was used to achieve fast and highly efficient image acquisitions. These optimizations made it possible to perform an x-ray phase contrast tomographic measurement within an 8 min scan with density resolution of 2.4 mg/cm3. A maximum volume size of 13 × 13 × 6 mm3 was obtained with a single tomographic measurement with a voxel size of 6.5 μm. The scanning procedure using the triangle wave was applied to four-dimensional measurements in which highly sensitive three-dimensional x-ray imaging and a time-resolved dynamic measurement of biological samples were combined. A fresh tendon in the tail of a rat was measured under a uniaxial stretching and releasing condition. To maintain the freshness of the sample during four-dimensional phase contrast tomography, the temperature of the bathing liquid of the sample was kept below 10° using a simple cooling system. The time-resolved deformation of the tendon and each fascicle was measured with a temporal resolution of 5.7 Hz. Evaluations of cross-sectional area size, length of the axis, and mass density in the fascicle during a stretching process provided a basis for quantitative analysis of the deformation of tendon fascicle.

Reflective full‐color LCD using low‐temperature polysilicon TFTs in low‐frequency driving: Analysis of image persistence and flicker with scientific CMOS camera

AbstractImage persistence and flicker are major issues for low‐frequency driving of LCDs. Detailed investigation of the mechanisms that produce these phenomena, using image analysis with a scientific CMOS camera, enabled us to reduce it to acceptable levels. We successfully developed a 7.0‐in. WUXGA (1200 × RGBW × 1920) reflective color LCD driven by low‐temperature polysilicon TFTs at 1 Hz.

An integrative approach for analyzing hundreds of neurons in task performing mice using wide-field calcium imaging.

Advances in neurotechnology have been integral to the investigation of neural circuit function in systems neuroscience. Recent improvements in high performance fluorescent sensors and scientific CMOS cameras enables optical imaging of neural networks at a much larger scale. While exciting technical advances demonstrate the potential of this technique, further improvement in data acquisition and analysis, especially those that allow effective processing of increasingly larger datasets, would greatly promote the application of optical imaging in systems neuroscience. Here we demonstrate the ability of wide-field imaging to capture the concurrent dynamic activity from hundreds to thousands of neurons over millimeters of brain tissue in behaving mice. This system allows the visualization of morphological details at a higher spatial resolution than has been previously achieved using similar functional imaging modalities. To analyze the expansive data sets, we developed software to facilitate rapid downstream data processing. Using this system, we show that a large fraction of anatomically distinct hippocampal neurons respond to discrete environmental stimuli associated with classical conditioning, and that the observed temporal dynamics of transient calcium signals are sufficient for exploring certain spatiotemporal features of large neural networks.

Focus on lasers and imaging

Focus on lasers and imaging

Focus on photonics, biomedical optics, and microscopy

Focus on photonics, biomedical optics, and microscopy

高动态科学级CMOS相机系统的设计

高动态科学级CMOS相机系统的设计

Two-pulse structured illumination imaging.

Structured illumination (SI), which is an imaging technique that is employed in a variety of fields, permits unique possibilities to suppress unwanted signal contributions that carry misguiding information such as out-of-focus light or multiply scattered light. So far SI has been applied mostly for averaged imaging or for imaging of slowly occurring events because it requires three acquisitions (subimages) to construct the final SI image. This prerequisite puts technological constraints on SI that make "instantaneous" imaging of fast transient processes (occurring on submicrosecond time scales) very challenging and expensive. Operating SI with fewer subimages generates errors in the form of residual lines that stretch across the image. Here, a new approach that circumvents this limiting factor is presented and experimentally demonstrated. By judiciously choosing the intensity modulation, it is possible to extract an SI image from two subimages only. This development will allow standard double-pulsed lasers and interline transfer CCD or scientific CMOS cameras to be used to acquire temporally frozen SI images of rapidly occurring processes as well as to boost the frame-rate of current SI video systems; a technical advancement that will benefit both macro- and microscopic imaging applications.