A practical wide-field Raman imaging method with high spectral and spatial resolution

2018 ◽  
Vol 89 (8) ◽  
pp. 083103 ◽  
Author(s):  
Haibo Li ◽  
Wenhua Luo ◽  
Gan Li ◽  
Guangfeng Zhang ◽  
Pengcheng Zhang ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Raman Imaging ◽  
Imaging Method ◽  
Wide Field

scholarly journals Light sheet-excited spontaneous Raman imaging of a living fish by optical sectioning in a wide field Raman microscope

2012 ◽  
Vol 20 (15) ◽  
pp. 16195 ◽  
Author(s):  
Yusuke Oshima ◽  
Hidetoshi Sato ◽  
Hiroko Kajiura-Kobayashi ◽  
Tetsuaki Kimura ◽  
Kiyoshi Naruse ◽  
...  
Keyword(s):  
Light Sheet ◽  
Raman Imaging ◽  
Wide Field ◽  
Optical Sectioning

scholarly journals Label-free surface-sensitive photonic microscopy with high spatial resolution using azimuthal rotation illumination

2019 ◽  
Vol 5 (3) ◽  
pp. eaav5335 ◽  
Author(s):  
Yan Kuai ◽  
Junxue Chen ◽  
Xi Tang ◽  
Yifeng Xiang ◽  
Fengya Lu ◽  
...  
Keyword(s):  
Free Surface ◽  
Spatial Resolution ◽  
High Surface ◽  
Metal Films ◽  
Wide Field ◽  
Label Free ◽  
Dielectric Substrates ◽  
Surface Sensitivity ◽  
Order Of Magnitude ◽  
Culture Growth

Surface plasmon resonance microscopy (SPRM) with single-direction illumination is a powerful platform for biomedical imaging because of its wide-field, label-free, and high-surface-sensitivity imaging capabilities. However, two disadvantages prevent wider use of SPRM. The first is its poor spatial resolution that can be as large as several micrometers. The second is that SPRM requires use of metal films as sample substrates; this introduces working wavelength limitations. In addition, cell culture growth on metal films is not as universally available as growth on dielectric substrates. Here we show that use of azimuthal rotation illumination allows SPRM spatial resolution to be enhanced by up to an order of magnitude. The metal film can also be replaced by a dielectric multilayer and then a different label-free surface-sensitive photonic microscopy is developed, which has more choices in terms of the working wavelength, polarization, and imaging section, and will bring opportunities for applications in biology.

scholarly journals A wide field-of-view imaging DOAS instrument for two-dimensional trace gas mapping from aircraft

2015 ◽  
Vol 8 (12) ◽  
pp. 5113-5131 ◽  
Author(s):  
A. Schönhardt ◽  
P. Altube ◽  
K. Gerilowski ◽  
S. Krautwurst ◽  
J. Hartmann ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Point Sources ◽  
West Germany ◽  
Field Of View ◽  
Trace Gas ◽  
Optical Absorption Spectroscopy ◽  
Small Scale ◽  
Wide Field ◽  
Flight Altitude ◽  
Good Imaging

Abstract. The Airborne imaging differential optical absorption spectroscopy (DOAS) instrument for Measurements of Atmospheric Pollution (AirMAP) has been developed for the purpose of trace gas measurements and pollution mapping. The instrument has been characterized and successfully operated from aircraft. Nitrogen dioxide (NO2) columns were retrieved from the AirMAP observations. A major benefit of the push-broom imaging instrument is the spatially continuous, gap-free measurement sequence independent of flight altitude, a valuable characteristic for mapping purposes. This is made possible by the use of a charge coupled device (CCD) frame-transfer detector. A broad field of view across track of around 48° is achieved with wide-angle entrance optics. This leads to a swath width of about the same size as the flight altitude. The use of fibre coupled light intake optics with sorted light fibres allows flexible instrument positioning within the aircraft and retains the very good imaging capabilities. The measurements yield ground spatial resolutions below 100 m depending on flight altitude. The number of viewing directions is chosen from a maximum of 35 individual viewing directions (lines of sight, LOS) represented by 35 individual fibres. The selection is adapted to each situation by averaging according to signal-to-noise or spatial resolution requirements. Observations at 30 m spatial resolution are obtained when flying at 1000 m altitude and making use of all 35 viewing directions. This makes the instrument a suitable tool for mapping trace gas point sources and small-scale variability. The position and aircraft attitude are taken into account for accurate spatial mapping using the Attitude and Heading Reference System of the aircraft. A first demonstration mission using AirMAP was undertaken in June 2011. AirMAP was operated on the AWI Polar-5 aircraft in the framework of the AIRMETH-2011 campaign. During a flight above a medium-sized coal-fired power plant in north-west Germany, AirMAP clearly detected the emission plume downwind from the exhaust stack, with NO2 vertical columns around 2 × 1016 molecules cm−2 in the plume centre. NOx emissions estimated from the AirMAP observations are consistent with reports in the European Pollutant Release and Transfer Register. Strong spatial gradients and variability in NO2 amounts across and along flight direction are observed, and small-scale enhancements of NO2 above a motorway are detected.

Hyperspectral Raman Imaging Using a Spatial Heterodyne Raman Spectrometer with a Microlens Array

2020 ◽  
Vol 74 (8) ◽  
pp. 921-931 ◽  
Author(s):  
Ashley Allen ◽  
Abigail Waldron ◽  
Joshua M. Ottaway ◽  
J. Chance Carter ◽  
S. Michael Angel
Keyword(s):  
Raman Spectra ◽  
Spatial Resolution ◽  
Spectral Resolution ◽  
Diffraction Gratings ◽  
Complementary Metal Oxide Semiconductor ◽  
Microlens Array ◽  
Raman Imaging ◽  
Oxide Semiconductor ◽  
Raman Spectrometer ◽  
A Charge

A new hyperspectral Raman imaging technique is described using a spatial heterodyne Raman spectrometer (SHRS) and a microlens array (MLA). The new technique enables the simultaneous acquisition of Raman spectra over a wide spectral range at spatially isolated locations within two spatial dimensions ( x, y) using a single exposure on a charge-coupled device (CCD) or other detector types such as a complementary metal-oxide semiconductor (CMOS) detector. In the SHRS system described here, a 4 × 4 mm MLA with 1600, 100 µm diameter lenslets is used to image the sample, with each lenslet illuminating a different region of the SHRS diffraction gratings and forming independent fringe images on the CCD. The fringe images from each lenslet contain the fully encoded Raman spectrum of the region of the sample “seen” by the lenslet. Since the SHRS requires no moving parts, all fringe images can be measured simultaneously with a single detector exposure, and in principle using a single laser shot, in the case of a pulsed laser. In this proof of concept paper, hyperspectral Raman spectra of a wide variety of heterogeneous samples are used to characterize the technique in terms of spatial and spectral resolution tradeoffs. It is shown that the spatial resolution is a function of the diameter of the MLA lenslets, while the number of spatial elements that can be resolved is equal to the number of MLA lenslets that can be imaged onto the SHRS detector. The spectral resolution depends on the spatial resolution desired, and the number of grooves illuminated on both diffraction gratings by each lenslet, or combination of lenslets in cases where they are grouped.

X-ray microtomographic imaging and analysis for basic research

2006 ◽  
Vol 21 (2) ◽  
pp. 125-131 ◽  
Author(s):  
J. H. Dunsmuir ◽  
S. Bennett ◽  
L. Fareria ◽  
A. Mingino ◽  
M. Sansone
Keyword(s):  
Spatial Resolution ◽  
Three Dimensional ◽  
Basic Research ◽  
Integrated Approach ◽  
Imaging Method ◽  
Structure Property ◽  
3D Images ◽  
X Ray ◽  
Structure Property Relationships ◽  
Essential Components

For research facilities with access to synchrotron X-ray sources, X-ray absorption microtomography (XMT) has evolved from an experimental imaging method to a specialized, if not yet routine, microscopy for imaging the three-dimensional (3D) distribution of linear attenuation coefficients and, in some cases, elemental concentration with micron spatial resolution. Recent advances in source and detector design have produced conventional X-ray source instruments with comparable spatial resolution but with lower throughput and without element specific imaging. Both classes of instrument produce 3D images for analysis. We discuss an integrated approach for the implementation of analytical XMT to support basic research into the structure-property relationships of a variety of materials. The essential components include instrumentation for collecting quantitative 3D images, a 3D image processing environment to address questions as to the quantity, composition, geometry, and relationships among the features in one or more images, and visualization to provide insight and communicate results. We give examples of image analysis of resolved and unresolved pore spaces of sandstones.

High-speed UV imaging of elves and lightning from space: first simultaneous detections from the Mini-EUSO and ASIM instruments

2020 ◽  
Author(s):  
Matteo Battisti ◽  
Enrico Arnone ◽  
Mario Bertaina ◽  
Marco Casolino ◽  
Olivier Chanrion ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
High Speed ◽  
Multispectral Imaging ◽  
Gamma Ray ◽  
Single Photon ◽  
Uv Light ◽  
Photon Counting ◽  
Space Station ◽  
Wide Field ◽  
First Time

<p>The search for the physical mechanisms of lightning, transient luminous events and terrestrial gamma-ray flashes is receiving an extraordinary support by new space observations that have recently become available. Next to lightning detectors on geostationary satellites, new low orbit experiments are giving an unprecedented insight in the very source of these processes. Looking at the physics behind these new observations requires however to have a variety of different instruments covering the same event, and this is proving extremely challenging. Here, we present observations of UV emissions of elves and lightning taken for the first time simultaneously from the two instruments Mini-EUSO and ASIM operating on the international space station. Mini-EUSO was designed to perform observations of the UV-light night emission from Earth. It is a wide field of view telescope (44°x44° square FOV) installed for the first time on October 2019 inside the Zvezda Module of the ISS, looking nadir through a UV transparent window. Its optical system consists of two Fresnel lenses for light collection. The light is focused onto an array of 36 multi-anode photomultiplier tubes (MAPMT), for a total of 2304 pixels. Each pixel has a footprint on ground of ~5.5 km. The instrument is capable of single-photon counting on three different timescales: a 2.5 microsecond (D1) and a 320 microsecond (D2) timescale with a dedicated trigger system, and a 40.96ms timescale (D3) used to produce a continuous monitoring of the UV emission from the Earth. ASIM is an experiment dedicated to lightning and atmospheric processes. Its Modular Multispectral Imaging Array (MMIA) is made of an array of 3 high speed photometers probing different wavelength sampling at rates up to 100 kHz, and 2 Electron Multiplication Charge Coupled Devices (EM-CCDs) with a sub-km spatial resolution with an 80° FOV and recording up to 12 frames per second. Mini-EUSO detected several bright atmospheric events like lightning and elves, with a few km spatial resolution and different time resolutions, probing therefore different stages of the electromagnetic phenomena. Observations from Mini-EUSO were simultaneously captured by ASIM instruments, allowing for the first time to compare and complement the capabilities of the two instruments with a time inter-calibration based on unambiguous series of lightning detections.</p>

scholarly journals Simultaneous multiview capture and fusion improves spatial resolution in wide-field and light-sheet microscopy

Optica ◽  
2016 ◽  
Vol 3 (8) ◽  
pp. 897 ◽  
Author(s):  
Yicong Wu ◽  
Panagiotis Chandris ◽  
Peter W. Winter ◽  
Edward Y. Kim ◽  
Valentin Jaumouillé ◽  
...  
Keyword(s):  
Spatial Resolution ◽  
Light Sheet ◽  
Wide Field ◽  
Light Sheet Microscopy

Noninvasive Tumor Imaging with High-Frequency Ultrasound and MicroPET in Small Animals

2007 ◽  
Vol 29 (4) ◽  
pp. 201-212 ◽  
Author(s):  
Ai-Ho Liao ◽  
Jeng-Jong Hwang ◽  
Chen-Han Li ◽  
Wen-Fang Cheng ◽  
Pai-Chi Li
Keyword(s):  
Spatial Resolution ◽  
Tumor Volume ◽  
Tumor Imaging ◽  
Tumor Hypoxia ◽  
Tumor Segmentation ◽  
Imaging Method ◽  
Mouse Tumor ◽  
Functional Information ◽  
High Frequency Ultrasound ◽  
Volume Measurements

In this study, we used a micro-ultrasound (microUS) system that we developed in-house as an alternative method for tumor growth calipers. In addition, microUS was combined with small-animal positron-emission tomography (microPET) for tumor metastatic assessment. MicroUS provides anatomical information that can be used for tumor volume measurements while microPET is a functional imaging method with positron-emitting radiophamaceuticals, such as 18F-labeled deoxyglucose, [18F]FDG. In this study, microUS and microPET were performed in a mouse tumor longitudinal study (2–8 weeks), both with 3D tumor segmentation and volume measurements. Compared with vernier calipers, microPET generally overestimated tumor volumes during weeks 2–4 due to its inadequate spatial resolution. During weeks 5–8, standard deviations of microPET results were large due to tumor hypoxia or necrosis. On the contrary, microUS tumor volume measurements were more reliable as they were less affected by these factors. Nonetheless, microUS is not able to provide functional information similar to that provided by microPET. Therefore, microUS and microPET are complementary to each other as microUS has superior spatial resolution and microPET provides functional information, such as hypoxia or necrosis in the progression of the tumor. With image registration and fusion, the combination can be a valuable tool for cancer research.

Sign in / Sign up

Export Citation Format

Share Document