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To examine the regional changes in human choroidal thickness following short-term exposure to hemifield myopic defocus using optical coherence tomography (OCT).The central 26˚ visual field of the left eye of 25 healthy young adults (mean age 26 ± 5 years) was exposed to 60 min of clear vision (control session), +3 D full-field, +3 D superior retinal and +3 D inferior retinal myopic defocus, with the right eye occluded. Choroidal thickness across the central 5 mm (17°) macular region was examined before and after 60 min of defocus using a high-resolution, foveal centred vertical OCT line scan, with optical defocus simultaneously imposed using a Badal optometer and cold mirror system mounted on a Spectralis OCT device.Averaged across the central 5 mm macular area, choroidal thickness decreased by -4 ± 7 μm during the control session (p = 0.01), most likely due to the unique stimulus conditions of this study. The mean macular choroidal thickness increased during full-field (+2 ± 8 μm), inferior retinal (+3 ± 7 μm) and superior retinal myopic defocus (+5 ± 9 μm), representing a significant thickening of the choroid compared to the control session (all p 0.05). The defocus induced changes in macular choroidal thickness differed between the superior and inferior hemiretinal regions (FThese findings provide evidence supporting a local regional choroidal response to myopic defocus in the human eye, with hemifield myopic defocus leading to significant thickening of the choroid localised to the retinal region exposed to defocus. The novel finding of a localised response of the human choroid to hemifield myopic defocus, particularly in the superior hemiretina, may have important implications in optimising the optical design of myopia control interventions.

Line scan cameras are semiconductor cameras used in many industrial environments. Most have just one photosensitive linear array, but some have single arrays with sensitivity for different colors (for example: RGB line scan camera with three arrays). A line scan camera can be used for one-dimensional measurements, such as determining the width of a gap, or for producing a two-dimensional image by moving either the camera or the object, like a photocopier or a fax machine. The main advantages of a line camera include high optical resolution and speed, the ability to synchronize each line and the freedom to produce an image of almost unrestricted length.

c-plane ZnO films were eptiaxially grown on c-GaN/sapphire substrate by MOCVD. Cathodoluminescence (CL) line scan was performed on the cross-sectional ZnO/GaN films. These CL spectra shapes show a variation along the growth direction with a peak position shift, which can be divided into three stages. The study of the three stages reflects the growth mode alteration from the interface between ZnO and GaN to the surface. (© 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A line-scan spectral imaging system was developed for online identification of wholesome and unwholesome freshly slaughtered chicken carcasses on commercial processing lines. Hyperspectral images acquired by the imaging system for 5,549 wholesome and 93 unwholesome chicken carcasses on a 140 bird per minute (bpm) processing line were analyzed to optimize region of interest size and location and determine key wavebands by which to implement online multispectral inspection based on single-waveband intensity and a two-waveband ratio. Multispectral inspection algorithms were developed for real-time online chicken inspection. The imaging system inspected over 100,000 chickens on the processing line during continuous operation and accurately identified over 99% of wholesome and over 96% of unwholesome chickens. A system of this type can perform food safety inspection tasks accurately and consistently on high-speed processing lines (e.g., at least 140 bpm), to help poultry processors improve production efficiency and satisfy increasing consumer demand for poultry products. PRACTICAL APPLICATIONS The line-scan spectral imaging system was designed as a tool to assist poultry processors in meeting the requirements of the HACCP-Based Inspection Models Project as implemented by Food Safety and Inspection Service (FSIS). The system is particularly well suited for presorting poultry carcasses on high-speed processing lines by removing systemically diseased birds prior to the inspection stations. This can increase efficiency and reduce cross-contamination risks by minimizing the presence and unnecessary processing of unwholesome birds on the processing line. Real-time data collection and prompt removal of unwholesome poultry carcasses can enhance the ability of FSIS to certify U.S. poultry products for both domestic and export markets. In addition, the spectral imaging methodology of this system has the potential for easy adaptation to other high-speed food processing tasks, particularly those involving automated inspection for quality indicators.

A line-scan echo planar spectroscopic imaging (LSEPSI) sequence was used to serially acquire spectra from 4096 voxels every 6.4 s throughout the breasts of nine female subjects in vivo. Data from the serial acquisitions were analyzed to determine the potential of the technique to characterize temperature changes using either the water frequency alone or the water-methylene frequency difference. Fluctuations of the apparent temperature change under these conditions of no heating were smallest using the water-methylene frequency difference, most probably due to a substantial reduction of motion effects both within and without the imaged plane. The approach offers considerable advantages over other methods for temperature change monitoring in the breast with magnetic resonance but suffers from some limitations, including the unavailability of lipid and water resonances in some voxels as well as a surprisingly large distribution of water-methylene frequency differences, which may preclude absolute temperature measurement. Magn Reson Med 58:1117–1123, 2007. © 2007 Wiley-Liss, Inc.

The detection of drainage patterns in an area of the Forest of Dean, Gloucestershire, provides an example of the usefulness of infra-red line-scan imagery. Resume Ľutilitye du thermometre pour rayons infra-rouge est demontree par la mise en evidence du reseau hydrographique dans laforet de Dean en Gloucestershire (Angleterre). Zusammenfassung Die Aufdeckung eines Drainage-Systems in einem Gebiet des Forest of Dean, Gloucestershire vermittelt ein Beispiel uber die Nutzlichkeit von linienweise abgetasteten fnfrarot-Aufnahmen.

Purpose To investigate and measure apparent diffusion coefficient (ADC) and fractional anisotropy (FA) values using data obtained with line-scan diffusion-weighted imaging (DWI) of human brains on a 0.2 Tesla MR imager. Materials and Methods Diffusion-tensor imaging (DTI) was performed on eight healthy volunteers. The signal-to-noise ratios (SNRs) of white matter and cerebrospinal fluid were measured. ADC and FA were also measured from the data obtained from all subjects. Three-dimensional corticospinal fiber tracts were reconstructed from the DT images and a qualitative evaluation was done. Results The total scan time was 52 minutes 30 seconds for 18 slices with full-tensor images covering the whole brain. The ADCs and FAs show the appropriate values, in comparison with values obtained at high field strength in previous studies. Corticospinal fibers were demonstrated more clearly on images obtained at 0.2 T than at 1.5T. Conclusion DTI at low field strength may be feasible for clinical use to estimate the white matter of brain with limited coverage, which often may be sufficient. J. Magn. Reson. Imaging 2005. © 2005 Wiley-Liss, Inc.

The spinal cord is an important part of the nervous system and provides the connection of the brain with the periphery. It consists not only of a large number of longitudinal fibers, but also contains collateral fibers and a central gray matter structure, which are part of autonomous circuits. Magnetic resonance diffusion tensor imaging can reveal this complex fiber architecture in great detail. This report summarizes the normal findings for ADC, diffusion anisotropy, and diffusion eigenvector directions in the spinal cord. Sagittal and axial diffusion-weighted images of the spinal cord were obtained with line scan diffusion imaging (LSDI) in adults, children, infants, and a spinal cord specimen.

Purpose To investigate the dependence of line scan diffusion imaging (LSDI) in the lumbar vertebral discs on diffusion weighting, fat suppression (FS), and postprocessing noise correction. Materials and Methods Eleven normal volunteers were scanned using 4 b-value and 12 b-value LSDI protocols, with and without FS. Three repeated four b-value scans were performed for evaluation of the reproducibility of apparent diffusion coefficient (ADC) values calculated with mono- and biexponential decay models. Two-point ADC analysis for 12 b-value scans was performed with and without noise correction to evaluate the ADC dependence on diffusion weighting. Correlations between different ADC calculation and acquisition methods were evaluated. Results Monoexponential ADC measures had a coefficient of variation (CV) under 3%, while use of a constrained biexponential increased the CV to 6% to 9%. Strong dependence on b-value was seen from chemically shifted marrow fat signal and noise. These systematic variations in ADC were eliminated using noise correction and FS. ADC values from 4 and 12 b-value FS scans correlated strongly (R2 = 0.91), while biexponentially derived ADC values correlated moderately well with the FS ADC (R2 = 0.51). Conclusion LSDI gives reproducible ADC measurements in the lumbar discs, largely independent of b-value and signal-to-noise ratio (SNR) when used with noise correction and FS. J. Magn. Reson. Imaging 2005;21:482–488. © 2005 Wiley-Liss, Inc.

Quantitative T2 relaxation and diffusion imaging studies of a rat muscle edema model were performed in order to determine the effects of intra- and extracellular water compartmentation on the respective decay curves. The right hind paw of rats was injected with a carrageenan solution to generate edematous muscle. A Carr-Purcell-Meiboom-Gill (CPMG) imaging sequence was used to acquire T2 relaxation decay curves from both paws. A line scan diffusion imaging (LSDI) sequence was then used to acquire diffusion decay curves from the same paws over a wide b-factor range. Measurements were made from both edematous muscle (EM) and control muscle (CM). The EM and CM T2 relaxation decay curves were best fit with biexponential functions. The fraction of the fast T2 component dropped dramatically from approximately 0.95 in CM to 0.45 in EM, consistent with a water compartmentation model in which the fast and slow T2 components reflect intra- and extracellular water, respectively. Both CM and EM diffusion decay curves required biexponential fitting functions, and the diffusion coefficients of the fast and slow components were substantially larger in EM than CM. The fraction of the fast diffusion component, however, was not radically altered between CM and EM conditions (0.84 versus 0.89 for CM versus EM). Assuming a model in which intra- and extracellular water compartments are responsible for the fast and slow T2-decay components and for the slow and fast diffusion decay components, respectively, leads to fractional sizes of the diffusion components that are not supported by experiment. We conclude that intra- and extracellular water compartmentation is a reasonable interpretation for the two T2-decay components in both CM and EM but that other factors, such as restricted diffusion and/or alternate forms of water compartmentation like surface versus volume water, most probably have profound influences on the precise shapes of the diffusion decay curves, a complete understanding of which will require significant theoretical work.

Fat fractions and spectral T2 values of fat and water within the vertebral marrow of non-HIV- and HIV-infected men were measured with the use of a Carr-Purcell-Meiboom-Gill (CPMG) line scan spectroscopic imaging sequence. The fat fraction for the HIV-infected men (0.29 ± 0.08) was significantly lower (P < 0.05, Student's unpaired t-test) than the fat fraction found in non-HIV-infected men (0.40 ± 0.12). The mean water and fat T2 values did not differ between the two groups, and did not show any systematic dependence on fat fraction over the wide range of fat fractions encountered in this study. The marrow water and fat T2 values measured with the CPMG approach were markedly longer than the spectral T2 values reported by other groups using the more common point-resolved spectroscopy (PRESS) and stimulated-echo acquisition mode (STEAM) acquisitions. Proton spectroscopic studies of vertebral marrow revealed differences between non-HIV- and HIV-infected men that may prove useful for studying the effects of this disease and/or antiretroviral agents on body composition. Magn Reson Med 52:552–558, 2004. © 2004 Wiley-Liss, Inc.

The sensitivity of MR imaging to motion and susceptibility normally requires that the physician using intraoperative MRI cease surgical activity while image data sets are acquired. We demonstrate that line scan imaging allows the physician to continue operating without the delays caused by imaging. Consequently, patient anesthesia, surgery, and operating room time can be reduced. J. Magn. Reson. Imaging 2001;13:158-161.

Intraoperative line scan diffusion imaging (LSDI) on a 0.5 Tesla interventional MRI was performed during neurosurgery in three patients. Diffusion trace images were obtained in acute ischemic cases. Scan time per slice was 46 seconds and 94 seconds, respectively, for diffusion tensor images. Diagnosis of acutely developed vascular occlusion was confirmed with follow-up scans. White matter tracts were displayed with the principal eigenvectors and provided guidance for the tumor surgery. In all cases, the diagnostic utility of LSDI was established. J. Magn. Reson. Imaging 2001;13:115–119. © 2001 Wiley-Liss, Inc.

A line scan echo planar spectroscopic imaging (LSEPSI) sequence is presented which can rapidly produce 2D chemical shift imaging (CSI) data with minimal relaxation weighting and motion-related artifacts. The technique is based on successive “snapshot” 1D CSI acquisitions of individual tissue columns, and avoids T1 saturation problems associated with the short TR periods needed for very rapid scanning with either conventional or echo planar-based 2D CSI methods. Potential applications include rapid fat/water spectral quantitation in the abdomen and internally referenced temperature monitoring for interventional procedures. Magn Reson Med 44:521–524, 2000. © 2000 Wiley-Liss, Inc.

This paper presents an approximate multiple segment line scan-conversion method — the Slope Table Method. The statistics show that the new method can increase the percentage of multiple segment lines (i.e., lines with more than one segment) in an N×N raster area from about 39% to more than 99%. In software implementation for scan-conversion and antialiasing of randomly generated lines, this method is on average more than 6 times faster than Gupta's antialiasing line algorithm. Compared with other line scan-conversion methods, the method may choose pixels which are not the closest to the line (i.e., error pixels). Here the paper demonstrates that the visual effect is acceptable in most applications with the error pixels.

A new approach is presented for rapid and continuous monitoring of cerebral perfusion which is based upon line-scan MR column imaging with arterial spin tagging (AST) of endogenous water. Spin tagging of arterial water protons is accomplished using adiabatic fast passage inversion, followed by acquisition of the perfusion sensitive MR signal from a column placed at the desired level through the brain using line scan localization techniques. A perfusion sensitive line scan is followed by a non-perfusion sensitive line scan, and perfusion is calculated pixel-by-pixel from the intensity difference of the two lines. Continuous perfusion measurements are reported with temporal resolution of 10 s in pixels of volume 0.027 cm3 or less. Examples of the methodology are given during hypercapnic challenge induced with carbon dioxide, and during an ischemic event induced by reversible middle cerebral artery occlusion. The method is also used to characterize the signal response as a function of arterial inversion time and post inversion acquisition delay. These methods permit rapid and continuous monitoring of cerebral perfusion with high spatial resolution, and can be interleaved with MR measurements of diffusion and T1 to follow the progression of cerebral events during physiological or pharmacological intervention. Copyright © 1999 John Wiley & Sons, Ltd.

A time-dependent set of line scans across an erythrocyte was recorded by a phase contrast laser scanning microscope. A method for edge detection, based on a two-stage fitting procedure of the theoretical intensity distribution in a line scan of phase contrast image to the experimental one, is suggested. Time-resolved fluctuations of the human erythrocyte's edge were obtained, employing this method. The same procedure was carried out for a metallic strip yielding a test for the background noise level. The suggested method was applied in examining the effect of chemical crosslinking and thiol reduction on cell membrane fluctuations of human erythrocytes.

We present a new method for scan-converting a straight line. A scan-converted straight line may contain many pixel segments of identical shapes. Therefore, instead of scan-converting the whole line step by step, we can scan-convert multiple segments of a line through copying and replicating. With a few modifications to the existing algorithms, we can significantly speed up the scan-conversion process. The algorithm can be implemented in the hardware, further speeding up the process. The hardware design for the new algorithm is provided. We prove that we can speed up all existing line scan-conversion algorithms on the average 3 times.

A nuclear magnetic resonance (NMR) imaging and display method for the observation of the continuous motion of objects is presented. By modifying a line scan technique, the spin-density distribution along a line is displayed in succession. Although spatial information is limited to only one dimension, the motion of the object is recorded at intervals of 55 ms by using a commercially available NMR imaging system. In a phantom study, this method yielded accurate velocity measurements along a single axis. When the method was applied to the human chest, an image analogous to that of M-mode echocardiography was obtained. This method, which can be called spin-echo M-mode NMR imaging, approaches the functional analysis of cardiac wall motion in regions where echocardiography is not possible. The effects of respiratory motion on the left ventricular wall were recorded in addition to its intrinsic contractile motion in an image obtained along a line parallel to the cranio-caudal axis of the body. The advantages of this method to assess cardiac wall motion in a patient with an arrhythmia were also demonstrated.

We describe a system which forms MR angiographic images at high speed. Multiple axial sections are imaged sequentially using a 2DFT GRASS sequence with TR/TE 50/15 ms, 64 phase encodings per image. Reconstruction and projection of each image are performed immediately (within 220 ms) after data for that image are acquired. The projection angiogram is constructed line by line as the scan progresses, thereby totally eliminating any additional time required for reconstruction and projection.

Green light-emitting GaP:N diodes (LED's) are investigated at room temperature using a scanning electron probe microanalyzer. Integral cathodoluminescence (CL) line scans across the p-n junction are carried out. The CL line scan is discussed in connection with the depth of the p-n junction and in comparison with the external quantum efficiency of the diodes. A higher concentration of non-radiative recombination centres are detected in some cases close to the p-n junction in the n-region. The injection ratio (under the forward-bias condition) is determined comparing CL with the electroluminescence. Mit einem Elektronenstrahlmikroanalysator werden grun leuchtende GaP:N-Dioden (LED's) bei Raumtemperatur untersucht. Linienscans der integralen Katodolumineszenz werden uber dem pn-Ubergang durchgefuhrt. Die Katodolumineszenzprofile werden in Verbindung mit der Tiefe der pn-Ubergange und mit der auseren Quantenausbeute der Dioden diskutiert. In einigen Fallen wird eine Ansammlung von nichtstrahlenden Rekombinationszentren im n-Gebiet nahe dem pn-Ubergang nachgewiesen. Aus dem Vergleich der Katodolumineszenz mit der Elektrolumineszenz wird das Injektionsverhaltnis unter Flusspannung bestimmt.

A new NMR imaging technique is described. A selective excitation is given in a line-shaped focusing field. The spin distribution in the one-dimension line-shaped excitation region is detected with a linear magnetic field gradient. The methods of generating the line-shaped magnetic focusing field and its scanning are described together with the selective excitation characteristic. Experiments of imaging with an 819-kHz pulsed NMR system and their results are shown. The data collection time of the method was examined, showing much shorter time than conventional line-scanning methods. This is because the spin excitation is carried out only for a necessary region. When a single slice is required, the imaging time can be about the same period as in a conventional NMR-CT.

Both the barrier electron voltaic effect (charge collection) current and the cathodoluminescence intensity were recorded as the electron beam was scanned across p–n junctions normal to the surface of GaP diodes. Mid-points for each type of trace were defined and found to be separated by a distance (the CL–CC shift) which correlated with device efficiency. It was found that the magnitude of this shift depended also on the wavelength of light that was detected. The form of the charge collection traces recorded on scanning across the junctions varied with the electron beam voltage in the range from 10 to 30 kV in a simple manner which is however inexplicable in terms of the theories of the barrier electron voltaic effect which were found to apply in the case of GaAs p–n junctions [3]. Es wurden fur den Fall der Elektronenstrahlabtastung uber p–n-Ubergangen senkrecht zur Oberflache von GaP-Dioden sowohl der Barrierenphotospannungseffekt (Ladungssammlung)-Strom als auch die Kathodolumineszenzintensitat aufgezeichnet. Mittelpunkte fur beide Arten von aufgezeichneten Kurven wurden definiert, und es wurde gefunden, das sie durch einen Abstand (die CL–CC-Verschiebung) getrennt sind, der mit dem Wirkungsgrad des Bauelementes korreliert ist. Es wird gefunden, das die Grose der Verschiebung auch von der Wellenlange des nachgewiesenen Lichtes abhangig ist. Die Form der Kurven der Ladungssammlung, die beim Abtasten uber den Ubergang aufgezeichnet werden, variiert mit der Elektronenstrahlspannung im Bereich von 10 bis 30 kV in einfacher Weise, die jedoch mit den Theorien des Barrierenphotospannungseffektes, die fur den Fall der GaAs-p–n-Ubergange [3] gultig sind, nicht erklarbar sind.

Line scan traces of the barrier electron voltaic effect (charge collection) current recorded on scanning normally across the p-n junctions of GaAs lasers are reported. It is shown that in the n-type material they have the form I = A exp (−x/L1) + B exp (−x/L2) + C where X is the distance of the incident beam from the junction, L1 is the minority carrier diffusion length, L2 = α−1 where α is the infrared absorption coefficient and C which is the specimen current appeared because the amplifier was connected between the n-type material and earth. The value of α varies with X due to the self-absorption of the shorter wavelengths of the infra-red recombination radiation spectrum. The quantitative values of L1 and L2, and the ratios of A to B and to C were found to be in agreement with theoretical expectations. On the p-side the signal has the form I = A exp (−x/L1). Es werden Zeilenabtastkurven des Barrierenphotoeffekt (Ladungssammlung)-Stromes, der senkrecht zum p-n-Ubergang von GaAs-Lasern abgetastet wurde, mitgeteilt. Es wird gezeigt, das sie in n-leitendem Material die Form I = A exp (−x/L1) + B exp (−x/L2) + C haben, wobei X der Abstand des einfallenden Strahles vom Ubergang, L1 die Diffusionslange der Minoritatstrager, L2 = α−1 (α ist der Infrarotabsorptionskoeffizient) ist und wobei C, der Probenstrom, auftritt, weil der Verstarker zwischen dem n-leitenden Material und Erde geschaltet war. Infolge der Selbstabsorption der kurzeren Wellenlangen des infraroten Rekombinationsstrahlungsspektrums variiert der Wert von α mit X. Die quantitativen Grosen von L1 und L2, und die Verhaltnisse von A zu B und zu C befinden sich in Ubereinstimmung mit theoretischen Erwartungen. Auf der p-Seite hat das Signal die Form I = A exp (−x/L1).