Journal articles: 'Optical polarization and confocal laser microscopy'

1

Turner, JN, DH Szarowski, DP Barnard, JS Deitch, JW Swann, and K. Smith. "Confocal laser scanned microscopy: Optimized reflection mode." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 142–43. http://dx.doi.org/10.1017/s0424820100152689.

Full text

Abstract:

Most biological applications of confocal laser scanned microscopy (CLSM) involve the use of selective stains. Some of these stains provide image contrast by reflecting more light than the background. Unfortunately, reflected light from internal optical surfaces can also reach the detector, and the resultant spurious signal be superimposed on the image. When the specimen signal approaches or is less than that of the internal reflections, image degradation results. Due to the low reflectivity of biological stains, this situation is common. The image signal is also reduced as a function of depth in the specimen due to attenuation by surrounding tissue (stained or unstained), making the problem more severe because the internal reflections remain constant. This attenuation can limit the maximum depth at which optical sections are recorded. The spurious signals from these internal reflections can saturate parts of the field suppressing image information, and/or adversely influencing digital processing by establishing unrealistic intensity baselines and scales. Polarization optics have been proposed to reduce the effect of internal reflections. We report the installation of such components, and their use in imaging three important selective stains.

APA, Harvard, Vancouver, ISO, and other styles

2

Lakkakorpi, J. T., and H. J. Rajaniemi. "Application of the immunofluorescence technique and confocal laser scanning microscopy for studying the distribution of the luteinizing hormone/chorionic gonadotropin (LH/CG) receptor on rat luteal cells." Journal of Histochemistry & Cytochemistry 39, no. 4 (April 1991): 397–400. http://dx.doi.org/10.1177/39.4.2005369.

Full text

Abstract:

We used confocal scanning microscopy to study the semi-quantitative distribution of luteinizing hormone/chorionic gonadotropin (LH/CG) receptors on rat luteal cells at both the two- and the three-dimensional level. The receptors were visualized in 6-microns sections of pseudopregnant rat ovaries using polyclonal rabbit antiserum to hCG-affinity-purified LH/CG receptor in conjunction with rhodamine-conjugated anti-rabbit immunoglobulins. Twenty to 30 optical sections were taken at different focal planes from representative luteal cells with a confocal laser scanning microscope and then processed digitally to two- and three-dimensional pseudocolored images. Distinct differences in fluorescence intensity could be demonstrated at both the two- and the three-dimensional level on the luteal cell surfaces, suggesting an uneven distribution of the LH/CG receptors on the cell membranes. This probably results in the compartmentalization and polarization of luteal cell function.

APA, Harvard, Vancouver, ISO, and other styles

3

Campagnola, P. J., and L. M. Loew. "Second Harmonic Generation Imaging (SHG) in the Non-Linear Optical Microscopy of Living Cells." Microscopy and Microanalysis 4, S2 (July 1998): 414–15. http://dx.doi.org/10.1017/s1431927600022194.

Full text

Abstract:

In recent years there has been considerable interest in two and three-photon excited fluorescence in laser scanning optical microscopy. Because absorption is confined tot he focal plane of the objective, these techniques provide intrinsic optical sectioning without the use of a confocal aperture. In addition, photobleaching and phototoxicity are greatly reduced above and below the focal plane. We have adapted a two-photon microscope to utilize surface second harmonic generation (SHG) as a new contrast mechanism for nonlinear optical biological imaging.Surface SHG was first described by Shen [1] and arises from the second order nonlinear susceptibility, χ(2). Signal will only arise from a non-centrosymmetric environment such as an interfacial region. Thus this technique has the potential to probe cellular membranes at high specificity. Further, since SHG results from an induced polarization and not absorption, photobleaching considerations are greatly reduced over fluorescence based methods.

APA, Harvard, Vancouver, ISO, and other styles

4

He, Yaling, Xiaomin Wang, Jie Hu, Qiang Zhou, and Hui Chen. "Effect of Cu content on exfoliation corrosion and electrochemical corrosion of A7N01 aluminum alloy in EXCO solution." International Journal of Modern Physics B 31, no. 16-19 (July 26, 2017): 1744005. http://dx.doi.org/10.1142/s0217979217440052.

Full text

Abstract:

The exfoliation corrosion (EXCO) sensitivities and electrochemical corrosions of A7N01 aluminum (Al) alloys with 0.074% and 0.136% Cu contents were investigated in EXCO solution. The exfoliation corrosion developed more rapidly for the alloy with 0.136% Cu by expressing higher exfoliation rate and deeper corrosion pits as observed by SEM and laser confocal scanning microscopy (LCSM). In EXCO solution, the alloy with 0.136% Cu content showed lower open-circuit potential (OCP) than the alloy with 0.074% Cu content. The alloy with 0.136% Cu content had bigger “hysteresis loop” in cyclic polarization curve which meant lower self-passivation ability. In electrochemical impedance spectroscopy plot, its curvature radius and capacitance index were lower. The electrochemical test results revealed that the alloy with 0.136% Cu content showed more severe electrochemical corrosion than the alloy with 0.074% Cu content, consistent with the exfoliation corrosion results. The microstructures of two alloys were observed through optical microscopy (OM) and transmission electron microscopy (TEM). The continuous distribution of the equilibrium precipitate [Formula: see text]-MgZn2 on grain boundaries, the decreasing of the width of precipitate-free zone (PFZ) and the coarse Cu–Fe–Si–rich phase were responsible for the higher corrosion sensitivity of the Al alloy with 0.136% Cu than that of Al alloy with 0.074% Cu content in EXCO solution.

APA, Harvard, Vancouver, ISO, and other styles

5

Stremplewski, Patrycjusz, Maciej Nowakowski, Dawid Borycki, and Maciej Wojtkowski. "Fast method of speckle suppression for reflection phase microscopy." Photonics Letters of Poland 10, no. 4 (December 31, 2018): 118. http://dx.doi.org/10.4302/plp.v10i4.850.

Full text

Abstract:

Light propagating in turbid medium is randomly altered by optical inhomogeneities, which not only change the momentum and polarization of light but also generate a speckle pattern. All these effects strongly limit capabilities of laser based, quantitative phase–sensitive optical biomedical imaging modalities by hindering a reconstruction of phase distribution. Here we introduce the method of rapid incident light modulation, which allows to suppress speckle noise and preserve the spatial phase distribution. We implement this approach in the full-field Michelson interferometer, where the incident light is modulated using the digitalmicromirror device (DMD). Full Text: PDF ReferencesF. Zernike, "Phase contrast, a new method for the microscopic observation of transparent objects part II," Physica 9, 974-986 (1942). CrossRef M. C. Pitter, C. W. See, and M. G. Somekh, "Full-field heterodyne interference microscope with spatially incoherent illumination," Opt. Lett. 29, 1200-1202 (2004). CrossRef N. B. E. Sawyer, S. P. Morgan, M. G. Somekh, C. W. See, X. F. Cao, B. Y. Shekunov, and E. Astrakharchik, "Wide field amplitude and phase confocal microscope with parallel phase stepping," Review of Scientific Instruments 72, 3793-3801 (2001). CrossRef G. W. John and I. H. Keith, "A diffuser-based optical sectioning fluorescence microscope," Measurement Science and Technology 24, 125404 (2013). CrossRef S. Lowenthal and D. Joyeux, "Speckle Removal by a Slowly Moving Diffuser Associated with a Motionless Diffuser," J. Opt. Soc. Am. 61, 847-851 (1971). CrossRef S. Kubota and J. W. Goodman, "Very efficient speckle contrast reduction realized by moving diffuser device," Applied Optics 49, 4385-4391 (2010). CrossRef Y. Li, H. Lee, and E. Wolf, "The effect of a moving diffuser on a random electromagnetic beam," Journal of Modern Optics 52, 791-796 (2005). CrossRef C.-Y. Chen, W.-C. Su, C.-H. Lin, M.-D. Ke, Q.-L. Deng, and K.-Y. Chiu, "Reduction of speckles and distortion in projection system by using a rotating diffuser," Optical Review 19, 440-443 (2012). CrossRef J. Lehtolahti, M. Kuittinen, J. Turunen, and J. Tervo, "Coherence modulation by deterministic rotating diffusers," Opt. Express 23, 10453-10466 (2015). CrossRef J.-W. Pan and C.-H. Shih, "Speckle reduction and maintaining contrast in a LASER pico-projector using a vibrating symmetric diffuser," Opt. Express 22, 6464-6477 (2014). CrossRef J. I. Trisnadi, "Hadamard speckle contrast reduction," Optics Letters 29, 11-13 (2004). CrossRef M. Szkulmowski, I. Gorczynska, D. Szlag, M. Sylwestrzak, A. Kowalczyk, and M. Wojtkowski, "Efficient reduction of speckle noise in Optical Coherence Tomography," Opt. Express 20, 1337-1359 (2012). CrossRef J. W. Goodman, Speckle phenomena in optics: theory and applications (Roberts and Company Publishers, 2006). DirectLink Y. Choi, P. Hosseini, W. Choi, R. R. Dasari, P. T. C. So, and Z. Yaqoob, "Dynamic speckle illumination wide-field reflection phase microscopy," Opt. Lett. 39, 6062-6065 (2014). CrossRef Y. Choi, T. D. Yang, K. J. Lee, and W. Choi, "Full-field and single-shot quantitative phase microscopy using dynamic speckle illumination," Opt. Lett. 36, 2465-2467 (2011). CrossRef R. Zhou, D. Jin, P. Hosseini, V. R. Singh, Y.-h. Kim, C. Kuang, R. R. Dasari, Z. Yaqoob, and P. T. C. So, "Modeling the depth-sectioning effect in reflection-mode dynamic speckle-field interferometric microscopy," Optics Express 25, 130-143 (2017). CrossRef M. Schmitz, T. Rothe, and A. Kienle, "Evaluation of a spectrally resolved scattering microscope," Biomedical optics express 2, 2665-2678 (2011). CrossRef P. Judy, The line spread function and modulation transfer function of a computer tomography scanner, Med. Phys (1976), Vol. 3, pp. 233-236. CrossRef

APA, Harvard, Vancouver, ISO, and other styles

6

Xie, Xiang, Ju Tan, Dangheng Wei, Daoxi Lei, Tieying Yin, Junli Huang, Xiaojuan Zhang, Juhui Qiu, Chaojun Tang, and Guixue Wang. "In vitro and in vivo investigations on the effects of low-density lipoprotein concentration polarization and haemodynamics on atherosclerotic localization in rabbit and zebrafish." Journal of The Royal Society Interface 10, no. 82 (May 6, 2013): 20121053. http://dx.doi.org/10.1098/rsif.2012.1053.

Full text

Abstract:

Atherosclerosis (AS) commonly occurs in the regions of the arterial tree with haemodynamic peculiarities, including local flow field disturbances, and formation of swirling flow and vortices. The aim of our study was to confirm low-density lipoprotein (LDL) concentration polarization in the vascular system in vitro and in vivo , and investigate the effects of LDL concentration polarization and flow field alterations on atherosclerotic localization. Red fluorescent LDL was injected into optically transparent Flk1: GFP zebrafish embryos, and the LDL distribution in the vascular lumen was investigated in vivo using laser scanning confocal microscopy. LDL concentration at the vascular luminal surface was found to be higher than that in the bulk. The flow field conditions in blood vessel segments were simulated and measured, and obvious flow field disturbances were found in the regions of vascular geometry change. The LDL concentration at the luminal surface of bifurcation was significantly higher than that in the straight segment, possibly owing to the atherogenic effect of disturbed flow. Additionally, a stenosis model of rabbit carotid arteries was generated. Atherosclerotic plaques were found to have occurred in the stenosis group and were more severe in the stenosis group on a high-fat diet. Our findings provide the first ever definite proof that LDL concentration polarization occurs in the vascular system in vivo . Both lipoprotein concentration polarization and flow field changes are involved in the infiltration/accumulation of atherogenic lipids within the location of arterial luminal surface and promote the development of AS.

APA, Harvard, Vancouver, ISO, and other styles

7

Łosiewicz, Bożena, Patrycja Osak, Joanna Maszybrocka, Julian Kubisztal, and Sebastian Stach. "Effect of Autoclaving Time on Corrosion Resistance of Sandblasted Ti G4 in Artificial Saliva." Materials 13, no. 18 (September 18, 2020): 4154. http://dx.doi.org/10.3390/ma13184154.

Full text

Abstract:

Titanium Grade 4 (Ti G4) is the most commonly used material for dental implants due to its excellent mechanical properties, chemical stability and biocompatibility. A thin, self-passive oxide layer with protective properties to corrosion is formed on its surface. However, the spontaneous TiO2 layer is chemically unstable. In this work, the impact of autoclaving time on corrosion resistance of Ti G4 in artificial saliva solution with pH = 7.4 at 37 °C was studied. Ti G4 was sandblasted with white Al2O3 particles and autoclaved for 30–120 min. SEM, EDS, 2D roughness profiles, confocal laser scanning microscopy, and a Kelvin scanning probe were used for the surface characterization of the Ti G4 under study. In vitro corrosion resistance tests were conducted using open circuit potential, polarization curves, and electrochemical impedance spectroscopy measurements. It was found that Sa parameter, electron work function, and thickness of the oxide layers, determined based on impedance measurements, increased after autoclaving. The capacitive behavior and high corrosion resistance of tested materials were revealed. The improvement in the corrosion resistance after autoclaving was due to the presence of oxide layers with high chemical stability. The optimal Ti G4 surface for dentistry can be obtained by sandblasting with Al2O3 with an average grain size of 53 µm, followed by autoclaving for 90 min.

APA, Harvard, Vancouver, ISO, and other styles

8

Ohkubo, Shinya. "Development of Birefringence Confocal Laser Scanning Microscope and its Application to Sample Measurements." Journal of Robotics and Mechatronics 31, no. 6 (December 20, 2019): 926–33. http://dx.doi.org/10.20965/jrm.2019.p0926.

Full text

Abstract:

A new laser microscope is developed to obtain depth-direction birefringence information of optically anisotropic samples, which cannot be obtained by a conventional polarization microscope. As a result, birefringence tomographic images are now available and the method should be helpful for sample evaluations.

APA, Harvard, Vancouver, ISO, and other styles

9

Steinbach, Gábor, István Pomozi, Ottó Zsiros, László Menczel, and Győző Garab. "Imaging anisotropy using differential polarization laser scanning confocal microscopy." Acta Histochemica 111, no. 4 (July 2009): 317–26. http://dx.doi.org/10.1016/j.acthis.2008.11.021.

Full text

APA, Harvard, Vancouver, ISO, and other styles

10

Turner, JN, DP Barnard, DH Szarowski, JW Swann, and K. Smith. "Confocal laser scanned microscopy: Analog preprocessing." Proceedings, annual meeting, Electron Microscopy Society of America 47 (August 6, 1989): 150–51. http://dx.doi.org/10.1017/s0424820100152720.

Full text

Abstract:

Confocal laser scanned images often have such a large dynamic range that interpretation is hampered. We employed analog preprocessing to overcome this limitation, using a homomorphic filter and a differentiator. Individual neurons in thick brain slices were injected with a fluorescent dye, and imaged as test objects. The dye density varied for different subcellular regions, and the specimen acted as an attenuater as a function of depth. Thus, each “optical section” had a large signal range that was extreme when the sections were stack to form projections or stereo pairs. Images of either the fine processes (low signal) with a saturated cell body, or a cell body (high signal) with loss of the fine processes resulted from standard methods, but the homomorphic filter and differentiator produced high quality images of both in the same field.

APA, Harvard, Vancouver, ISO, and other styles

11

Cheng, P. C., S. J. Pan, A. Shih, W. S. Liou, M. S. Park, T. Watson, J. Bhawalkar, and P. Prasard. "Two-Photon Laser Scanning Confocal Microscopy." Microscopy and Microanalysis 3, S2 (August 1997): 847–48. http://dx.doi.org/10.1017/s1431927600011120.

Full text

Abstract:

Two-photon fluorescence microscopy has become an important research tool in both biological and material sciences. The technique uses long wavelength, typically in the near IR, as the excitation light to obtain shorter wavelength fluorescence (e.g. visible light). Because of the low linear absorption coefficient of most biological and polymeric specimens, this technique allows deeper penetration of the excitation beam, achieving optical sectioning to a depth of 250μm or more into the specimen. As a result of the quadratic dependency of the two-photon induced fluorescence to the excitation intensity, the fluorescent emission and photobleaching are limited to the vicinity of focal spot. This capability of addressing a specimen’s 3D space allows exciting possibilities in biological researches, such as 3D photobleaching recovery experiment.Two-photon confocal fluorescence microscopy is ideal for the study of thick biological and material specimen in 3D. For example, Figure 1 shows a three-dimensional isosurface rendered image of a vascular bundle from a maize stem.

APA, Harvard, Vancouver, ISO, and other styles

12

McMillan, William. "Laser Scanning Confocal Microscopy for Materials Science." Microscopy Today 6, no. 5 (July 1998): 20–23. http://dx.doi.org/10.1017/s1551929500067791.

Full text

Abstract:

Confocal microscopy has gained great popularity in biology and medical research because of the ability to image three-dimensional objects at greater resolution than conventional optical microscopes. In a typical Laser Scanning Confocal Microscope (LSCM), the specimen stage is stepped up or down to collect a series of two-dimensional images (or slices) at each focal plane. Conventional light microscopes create images with a depth of field, at high power, of 2 to 3 μm. The depth of field of confocal microscopes ranges from 0.5 to 1.5 μm, which allows information to be collected from a well defined optical section rather than from most of the specimen. Therefore, due to this “thin” focal plane, out of focus light is virtually eliminated which results in an increase in contrast, clarity and detection.

APA, Harvard, Vancouver, ISO, and other styles

13

Yoon, Changsik, Yue Qi, Humberto Mestre, Cristina Canavesi, Olivia J. Marola, Andrea Cogliati, Maiken Nedergaard, Richard T. Libby, and Jannick P. Rolland. "Gabor domain optical coherence microscopy combined with laser scanning confocal fluorescence microscopy." Biomedical Optics Express 10, no. 12 (November 14, 2019): 6242. http://dx.doi.org/10.1364/boe.10.006242.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

Fujii, H., D. J. Wood, J. M. Papadimitriou, and M. H. Zheng. "Application of Confocal Laser Scanning Microscopy in Bone." Journal of Musculoskeletal Research 02, no. 01 (March 1998): 65–71. http://dx.doi.org/10.1142/s0218957798000093.

Full text

Abstract:

The optical sectioning method of confocal laser scanning microscopy provides higher resolution than standard light microscope techniques. The use of optical rather than physical sections for detailed histological analyses of bone obviates the need for either decalcification or complex plastic embedding processes which are required as a routine for the preparation of thin microtome sections. In this study we have used confocal laser scanning microscopy for the morphological analyses of fresh unembedding human cortical bone, bone allograft and bone cement interfaces. Our results have indicated that such an approach has provided a relatively easy and rapid means for the assessment of the histology of normal and pathological bone.

APA, Harvard, Vancouver, ISO, and other styles

15

ZHAO Wei-qian, 赵维谦, 任利利 REN Li-li, 盛. 忠. SHENG Zhong, 王. 允. WANG Yun, and 邱丽荣 QIU Li-rong. "Beam deflection scanning for laser confocal microscopy." Optics and Precision Engineering 24, no. 6 (2016): 1257–63. http://dx.doi.org/10.3788/ope.20162406.1257.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Cooper, M. S. "Imaging cellular dynamics using scanning laser confocal microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 1 (August 1992): 12–13. http://dx.doi.org/10.1017/s0424820100120461.

Full text

Abstract:

In recent years, the ability to image morphological dynamics and physiological changes in living cells and tissues has been greatly advanced by the advent of scanning laser confocal microscopy. Confocal microscopes employ optical systems in which both the condenser and objective lenses are focused onto a single volume element of the specimen. In practice, galvanometer-driven mirrors or acousto-optical deflectors are used to scan a laser beam over the specimen in a raster-like fashion through an epifluorescence microscope. The incident laser beam, as well as the collected fluorescent light, are passed through pinhole or slit apertures in image planes that are conjugate to the plane of the specimen. This method of illumination and detection prevents fluorescent light which is generated above and below the plane-of-focus from impinging on the imaging system's photodetector, thus rejecting much of the fluorescent light which normally blurs the image of a three-dimensional fluorescent specimen.

APA, Harvard, Vancouver, ISO, and other styles

17

Liedmann, W., and H. Quader. "Optical analysis of geological structures by confocal laser scanning microscopy." Science of Nature 78, no. 9 (September 1991): 413–14. http://dx.doi.org/10.1007/bf01133414.

Full text

APA, Harvard, Vancouver, ISO, and other styles

18

Clark Brelje, T., and Robert L. Sorenson. "Multi-color laser scanning confocal microscopy with a krypton/argon ion laser." Proceedings, annual meeting, Electron Microscopy Society of America 49 (August 1991): 406–7. http://dx.doi.org/10.1017/s0424820100086337.

Full text

Abstract:

Fluorescence is presently the most important imaging mode in biological confocal microscopy. The optical properties of laser scanning confocal microscopy (LSCM) are particularly favorable for fluorescence microscopy since the generally high signal-to-background ratio is enhanced by LSCM by rejecting out-of-focus fluorescent emissions. In addition, this improved imaging capability along the optical (z-)axis allows the optical sectioning of specimens by adjusting the plane of focus. This removes one of the most severe limitations of convential fluorescence microscopy, the necessity to examine monolayers of cells or thin sections of tissues.However, the advantages of LSCM for multi-color fluorscence microscopy are critically dependent on the availability of suitable light sources and fluorophores. By far the most commonly used light source is a small, air-cooled argon ion laser with emission wavelengths at 488 and 514 nm. Although the most frequently used fluorophores, fluorescein (FITC) and tetramethylrhodamine, can be excited by these wavelengths, it is impossible to specifically excite each fluorophore in the presence of the other fluorophore.

APA, Harvard, Vancouver, ISO, and other styles

19

Lemasters, John J. "Confocal microscopy of single living cells." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 792–93. http://dx.doi.org/10.1017/s0424820100140336.

Full text

Abstract:

The advent of laser scanning confocal microscopy solves the dilemma of studying thick specimens with optical microscopy by creating optical slices less than 1 μm in thickness. Increasingly, confocal microscopy is an essential analytical tool for studying the structure and physiology of living cells. Because confocal microscopy collects light from only a fraction of the specimen volume, greater illumination is required. Consequently, photodamage and photobleaching are greater considerations, especially for study for living cells where repeated measurements over time are desired. To minimize photodamage, laser intensity should be attenuated by 100-1000 fold, photomultiplier circuits should be operated at highest sensitivity, and stable fluorophores should be used. When these conditions are met, literally hundreds of high resolution confocal images can be obtained from single cells loaded with parameter sensitive fluorophores.The number of parameter-specific fluorophores useful for observing single living cells by confocal microscopy is large and increasing. By labeling with calcein and collecting serial images, the volume, shape and surface topography of single living cells are reconstructed with results rivaling scanning electron micrographs.

APA, Harvard, Vancouver, ISO, and other styles

20

M. SHOTTON, DAVID. "Confocal scanning optical microscopy and its applications for biological specimens." Journal of Cell Science 94, no. 2 (October 1, 1989): 175–206. http://dx.doi.org/10.1242/jcs.94.2.175.

Full text

Abstract:

Confocal scanning optical microscopy (CSOM) is a new optical microscopic technique, which offers significant advantages over conventional microscopy. In laser scanning optical microscopy (SOM), the specimen is scanned by a diffractionlimited spot of laser light, and light transmitted or reflected by the in-focus illuminated volume element (voxel) of the specimen, or the fluorescence emission excited within it by the incident light, is focused onto a photodetector. As the illuminating spot is scanned over the specimen, the electrical output from this detector is displayed at the appropriate spatial position on a TV monitor, thus building up a two-dimensional image. In the confocal mode, an aperture, usually slightly smaller in diameter than the Airy disc image, is positioned in the image plane in front of the detector, at a position confocal with the in-focus voxel. Light emanating from this in-focus voxel thus passes through the aperture to the detector, while that from any region above or below the focal plane is defocused at the aperture plane and is thus largely prevented from reaching the detector, contributing essentially nothing to the confocal image. It is this ability to reduce out-of-focus blur, and thus permit accurate non-invasive optical sectioning, that makes confocal scanning microscopy so well suited for the imaging and three-dimensional tomography of stained biological specimens. In this review, I explain the principles of scanning optical microscopy and blur-free confocal imaging, discuss the various imaging modes of confocal microscopy, and illustrate some of its early applications.

APA, Harvard, Vancouver, ISO, and other styles

21

ZHANG Yun-hai, 张运海, 杨皓旻 YANG Hao-min, and 孔晨晖 KONG Chen-hui. "Spectral imaging system on laser scanning confocal microscopy." Optics and Precision Engineering 22, no. 6 (2014): 1446–53. http://dx.doi.org/10.3788/ope.20142206.1446.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

Hurley, Neil F., Kazumi Nakamura, and Hannah Rosenberg. "Microporosity quantification using confocal microscopy." Journal of Sedimentary Research 91, no. 7 (July 15, 2021): 735–50. http://dx.doi.org/10.2110/jsr.2020.030.

Full text

Abstract:

ABSTRACT In carbonate rocks, pore diameters range in size over at least nine orders of magnitude, from submicrometer-scale voids to km-scale caves. This study is focused on micropores, which are defined as pore bodies with diameter ≤ 10 micrometers. Corresponding pore throats are generally ≤ 1 micrometer in diameter. To visualize and quantify microporosity, geologists commonly use pore casts, transmitted-light petrography, and scanning electron microscopy. Shortfalls exist in all of these techniques. Laser scanning confocal microscopy, a relatively new approach, provides a step change in our ability to image and quantify microporosity in carbonate rocks. Laser scanning confocal microscopy provides high-resolution (0.2-micrometers/pixel) images of micropores. Such pores are generally obscure or invisible using conventional petrography. In practice, confocal microscopy is applied to polished rock chips or thin sections that have been vacuum-pressure impregnated with epoxy. The laser light source interacts with fluorescent dye within the epoxy. Emitted fluorescent light, recorded using point-by-point illumination, indicates the physical location of pores. A pinhole, placed in front of the detector, eliminates out-of-focus light. Because each measurement is a single point, confocal microscopes scan along grids of parallel lines to provide optical images of planes at specified depths within the sample. Confocal microscopy is used to generate 2D and 3D images of pore bodies and throats. Results can be compared to laboratory-measured petrophysical properties, such as pore-throat diameters from mercury injection capillary pressure (MICP) data. Now, for the first time, we can compute pore-body to pore-throat size ratios without pore casts. These ratios are important, because they can be related to mercury recovery factors from imbibition MICP experiments.

APA, Harvard, Vancouver, ISO, and other styles

23

Tan, Jiu Bin, and Jian Liu. "Recent Advances in our Research on Ultrahigh Resolution Laser Confocal Microscopy." Key Engineering Materials 381-382 (June 2008): 11–14. http://dx.doi.org/10.4028/www.scientific.net/kem.381-382.11.

Full text

Abstract:

This paper presents the resent advances in our research on ultrahigh resolution laser confocal microscopy to further improve the accuracy of non-contact 3D measurement of micro-structural dimensions and profiles at the level of micron/nanometer with emphasis on ways and means to improve axial and lateral resolutions. A scan measuring technique based on differential confocal microscopy is developed using the difference in the distribution of the scanning spot on near and far confocal planes by keeping the detectors off-focus at equal distance before and after the conjugate image plane of the scanning spot. This differential confocal microscopic scan measuring technique can be used to double the measurement sensitivity and obviously expand the linear range to improve the axial resolution, and to locate the tracking zero point at the center of the linear range with the highest sensitivity to achieve the bipolar tracking properties. In addition, this new technique can be used to effectively suppress the light source intensity drift and detector electronic drift and noise to improve the S/N ratio. The differential confocal detection technique can be combined with the optical superresolving filtering technique to improve both lateral and axial resolutions, and the confocal detection technique based on micro optical arrays has a very promising potential application for improving of detection efficiency.

APA, Harvard, Vancouver, ISO, and other styles

24

Atkinson, Matthew R. "Polymer Characterization Using Confocal Scanning Laser Microscopy: A Review." Microscopy and Microanalysis 5, S2 (August 1999): 988–89. http://dx.doi.org/10.1017/s1431927600018262.

Full text

Abstract:

Confocal microscopy was developed in 1957 by Minski, who was awarded a patent for this work in 1961. Since that time many advances have been in new designs and implementations. There are two basic classes of confocal microscope: the Nipkow-disk-based confocal microscope which allow real-time direct viewing of the sample, and the confocal scanning laser microscopes (CSLM). The CSLM will be focussed on in this presentation.The CSLM scans a focussed beam over, across or through the sample, collecting the reflected, scattered or emitted light. This light is directed towards an optical spatial filter, which passes light returning from the on-axis focus position, and rejects light that is returning from anywhere else. By detecting the light passing through the spatial filter synchronously with the moving beam and/or sample, an image that has only in-focus information is acquired. Typically a set of images is acquired as the sample is moved through focus: from this “image stack” both an extended-focus image and topographic information can be obtained.

APA, Harvard, Vancouver, ISO, and other styles

25

U-Thainual, Paweena, and Do-Hyun Kim. "Comparison between optical-resolution photoacoustic microscopy and confocal laser scanning microscopy for turbid sample imaging." Journal of Biomedical Optics 20, no. 12 (August 10, 2015): 121202. http://dx.doi.org/10.1117/1.jbo.20.12.121202.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

U-Thainual, Paweena, and Do-Hyun Kim. "Comparison between optical-resolution photoacoustic microscopy and confocal laser scanning microscopy for turbid sample imaging." Journal of Biomedical Optics 20, no. 12 (September 10, 2015): 121306. http://dx.doi.org/10.1117/1.jbo.20.12.121306.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Lellouchi, D., F. Beaudoin, C. Le Touze, P. Perdu, and R. Desplats. "IR confocal laser microscopy for MEMS Technological Evaluation." Microelectronics Reliability 42, no. 9-11 (September 2002): 1815–17. http://dx.doi.org/10.1016/s0026-2714(02)00237-8.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

Lienau, Ch, A. Richter, A. Klehr, and T. Elsaesser. "Near‐field scanning optical microscopy of polarization bistable laser diodes." Applied Physics Letters 69, no. 17 (October 21, 1996): 2471–73. http://dx.doi.org/10.1063/1.117501.

Full text

APA, Harvard, Vancouver, ISO, and other styles

29

HUANG JING, LIANG RUI-SHENG, SITU DA, ZHANG KUN-MING, and TANG ZHI-LIE. "THE OPTICAL TRANSFER FUNCTION OF CONFOCAL SCANNING LASER MICROSCOPY WITH GAUSS SOURCE." Acta Physica Sinica 47, no. 8 (1998): 1289. http://dx.doi.org/10.7498/aps.47.1289.

Full text

APA, Harvard, Vancouver, ISO, and other styles

30

SAMATHAM, RAVIKANT, KEVIN G. PHILLIPS, and STEVEN L. JACQUES. "ASSESSMENT OF OPTICAL CLEARING AGENTS USING REFLECTANCE-MODE CONFOCAL SCANNING LASER MICROSCOPY." Journal of Innovative Optical Health Sciences 03, no. 03 (July 2010): 183–88. http://dx.doi.org/10.1142/s1793545810001064.

Full text

Abstract:

The mechanism of action of clearing agents to improve optical imaging of mouse skin during reflectance-mode confocal microscopy was tested. The dermal side of excised dorsal mouse skin was exposed for one hour to saline, glycerin, or 80% DMSO, then the clearing agent was removed and the dermis placed against a glass cover slip through which a confocal microscope measured reflectance at 488 nm wavelength. An untreated control was also measured. The axial attenuation of reflectance signal, R(zf) versus increasing depth of focus zf behaved as R = ρ exp (-μzf2G), where ρ is tissue reflectivity and μ is attenuation [cm-1]. The factor 2G accounts for the in/out path of photons, and the numerical aperture of the lens. The ρ, μ data were mapped to values of scattering coefficient (μs [cm-1]) and anisotropy of scattering (g). Images showed that glycerin significantly increased the g of dermis from about 0.7 to about 0.99, with little change in the μs of dermis at about 300 cm-1. DMSO and saline had only slight and inconsistent effects on g and μs.

APA, Harvard, Vancouver, ISO, and other styles

31

Yoshida, Shigeto, Shinji Tanaka, Mayuko Hirata, Ritsuo Mouri, Iwao Kaneko, Shiro Oka, Masaharu Yoshihara, and Kazuaki Chayama. "Optical biopsy of GI lesions by reflectance-type laser-scanning confocal microscopy." Gastrointestinal Endoscopy 66, no. 1 (July 2007): 144–49. http://dx.doi.org/10.1016/j.gie.2006.10.054.

Full text

APA, Harvard, Vancouver, ISO, and other styles

32

Watson, T. F. "Fact and Artefact in Confocal Microscopy." Advances in Dental Research 11, no. 4 (November 1997): 433–41. http://dx.doi.org/10.1177/08959374970110040901.

Full text

Abstract:

High-resolution confocal microscopic images may be made of either the surface of a sample or beneath the surface. These images can be likened to optical tomograms, giving thin (> 0.35 μm) slices up to 200 μm below the surface of a transparent tissue: With microscopes running under normal conditions, the optical section thickness will be >1 μm and the effective penetration into enamel and dentin a maximum of 100 μm. For maximum resolution, high-quality, high-numerical-aperture objectives should be used. Refractive index matching of the lens immersion media and the substrate will avoid distortions of images in the optical axis. Such errors could occur when imaging a considerable distance (> 40 μm) into a cell containing water, with an oil immersion objective above the cover slip. Care should be taken in the interpretation of computerized z axis reconstructions made from serial optical sections: Their validity should be checked with equivalent views made with the sample oriented in the same direction as the reconstruction. The use of fluorescent dyes in microscopy is a very powerful investigative technique. It is important that the dyes used not be labile and that they be well-fixed to the materials being examined, or the images may indicate the dye distribution rather than the material to which it is "attached". Multiple labeling experiments must have crossover control experiments to verify the distribution of the individual dyes. Valuable information can often be gained by combining information from both reflection and fluorescence images. Two-photon laser excitation of dyes gives the potential for greater depth penetration and improved resolution.

APA, Harvard, Vancouver, ISO, and other styles

33

Sha Dingguo, 沙定国, 江琴 Jiang Qin, 赵维谦 Zhao Weiqian, and 邱丽荣 Qiu Lirong. "Review and Expectation of Non-Coaxial Laser Confocal Microscopy." Chinese Journal of Lasers 37, no. 5 (2010): 1157–61. http://dx.doi.org/10.3788/cjl20103705.1157.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Zakharenko, Alexander Mikhailovich, and Kirill Sergeevich Golokhvast. "Using Confocal Laser Scanning Microscopy to Study Fossil Inclusion in Baltic Amber, a New Approach." Key Engineering Materials 806 (June 2019): 192–96. http://dx.doi.org/10.4028/www.scientific.net/kem.806.192.

Full text

Abstract:

We demonstrate that confocal laser scanning microscopy could be successfully used for rapid search of the organisms in the dark part of the amber samples. Combination of mid-infrared spectroscopy, confocal laser scanning microscopy and optical microscopy, allowed to identify and assess the quality of Baltic amber with fossil inclusion. Inclusion was identified as a spider from suborder Araneomorphae family Typhlopidae and it was struck by the mycelium.

APA, Harvard, Vancouver, ISO, and other styles

35

Kim, Yoon Soo, and Adya Singh. "Imaging Degraded Wood by Confocal Microscopy." Microscopy Today 6, no. 4 (May 1998): 14–15. http://dx.doi.org/10.1017/s1551929500067225.

Full text

Abstract:

The application of confocal laser scanning microscopy (CLSM) in the studies of biological materials is rapidly expanding because of the opportunity to produce sharp, high resolution images through optical sectioning and computer assisted 3-D reconstruction. At our institute CLSM is being used in a wide range of forestry and wood science studies.Recently we investigated the potential usefulness of CLSM in characterizing biologically degraded wood. The following are images produced from an archaeological wood which has been buried in a wet environment (rice field) for nearly 2,000 years in South Korea and is apparently degraded by bacteria. In an attempt to develop suitable techniques which can be used for routine examination of fragile degraded wood with CLSM, we have compared two different embedding methods for their suitability in preserving the integrity of cells. The embedding media are paraffin wax and LR White resin.

APA, Harvard, Vancouver, ISO, and other styles

36

Potma, Eric, Nicoletta Kahya, Wim P. de Boeij, and Douwe A. Wiersma. "A Multicolor Femtosecond Lightsource for (Multiphoton) Confocal Fluorescence Microscopy." Microscopy and Microanalysis 5, S2 (August 1999): 472–73. http://dx.doi.org/10.1017/s1431927600015683.

Full text

Abstract:

Recent advances in fluorescence microscopy add to the versatility of this optical technique and intensify its significance as an indispensable tool in biological research. Especially the use of multiphoton excitation offers the microscopist many advantages like inherent optical sectioning, reduced out-of-focus bleaching and higher penetration depths into the sample. In this regard, the commercial availability of pulsed solid-state lightsources like the Ti:Sapphire laser, that provide short pulses needed in the nonlinear multiphoton process, have paved the way for the routine implementation of multiphoton microscopy in the biologists laboratory. Although the spectral range of the commonly used Ti:Sapphire laser allows the application of two-photon fluorescence microscopy on chromophores that absorb in the range of 350-450 nm, a lasersource that enables the two-photon excitation of molecular probes at even shorter wavelengths (<350nm) would be highly beneficial.In this contribution we present a visible femtosecond optical parametric oscillator (OPO, Figure 1) that is ideally suited to excite molecular species at 285-335 nm by means of a two-photon process. Femtosecond pulses with durations as short as 30 fs can be generated within a tuning range from 570 to 670 nm. A cavity dumper incorporated in the laser cavity provides variable pulse repetition rates (single shot to 82 MHz).

APA, Harvard, Vancouver, ISO, and other styles

37

Zhu, Kaiyi, Hongfang Chen, Shulian Zhang, Zhaoyao Shi, Yun Wang, and Yidong Tan. "Frequency-Shifted Optical Feedback Measurement Technologies Using a Solid-State Microchip Laser." Applied Sciences 9, no. 1 (December 29, 2018): 109. http://dx.doi.org/10.3390/app9010109.

Full text

Abstract:

Since its first application toward displacement measurements in the early-1960s, laser feedback interferometry has become a fast-developing precision measurement modality with many kinds of lasers. By employing the frequency-shifted optical feedback, microchip laser feedback interferometry has been widely researched due to its advantages of high sensitivity, simple structure, and easy alignment. More recently, the laser confocal feedback tomography has been proposed, which combines the high sensitivity of laser frequency-shifted feedback effect and the axial positioning ability of confocal microscopy. In this paper, the principles of a laser frequency-shifted optical feedback interferometer and laser confocal feedback tomography are briefly introduced. Then we describe their applications in various kinds of metrology regarding displacement measurement, vibration measurement, physical quantities measurement, imaging, profilometry, microstructure measurement, and so on. Finally, the existing challenges and promising future directions are discussed.

APA, Harvard, Vancouver, ISO, and other styles

38

Göring, Lena, Markus Finkeldey, Falk Schellenberg, Carsten Brenner, Martin R. Hofmann, and Nils C Gerhardt. "Optical metrology for the investigation of buried technical structures." tm - Technisches Messen 85, no. 2 (February 23, 2018): 104–10. http://dx.doi.org/10.1515/teme-2017-0096.

Full text

Abstract:

Abstract In this paper, we present different optical metrology approaches for the investigation of buried technical structures. Contactless, potentially fast and non-destructive techniques such as optical beam induced current (OBIC), confocal laser scanning microscopy (CLSM) and digital holographic microscopy (DHM) are described. Their properties are illustrated by investigating the buried structures of a microcontroller.

APA, Harvard, Vancouver, ISO, and other styles

39

Beuerman, R. W., S. C. Kaufman, and K. A. Palkama. "Confocal Imaging: In Vivo and Clinical Applications." Microscopy Today 7, no. 2 (March 1999): 8–11. http://dx.doi.org/10.1017/s1551929500063859.

Full text

Abstract:

Confocal microscopy is a collection of optical techniques that are applied in a variety of hardware configurations. Design strategies for the application of these techniques have generally used laser light (Pawley, 1990). In most laboratories, basic research use has employed laser light in conjunction with a fluorescent substrate to generate an optical signal, either through direct application of a fluorescent material to cells or by the stimulation of a chromophore associated with an antibody which will identify a cellular protein under some specified experimental conditions, The use of confocal microscopy in this type of situation generally requires a standard research microscope, and the tissue may be situated on a slide or other type of container that will provide a stable, controlled environment.

APA, Harvard, Vancouver, ISO, and other styles

40

W. Piston, David. "Two-Photon Excitation Imaging of Glucose Metabolism in Living Tissue." Microscopy and Microanalysis 3, S2 (August 1997): 305–6. http://dx.doi.org/10.1017/s1431927600008412.

Full text

Abstract:

Two-photon excitation microscopy (TPEM) provides attractive advantages over confocal microscopy for three-dimensionally resolved fluorescence imaging and photochemistry. It provides three-dimensional resolution and eliminates background equivalent to an ideal confocal microscope without requiring a confocal spatial filter, whose absence enhances fluorescence collection efficiency. This results in inherent submicron optical sectioning by excitation alone. In practice, TPEM is made possible by the very high local instantaneous intensity provided by a combination of diffraction-limited focusing of a single laser beam in the microscope and the temporal concentration of 100 femtosecond pulses generated by a mode-locked laser. Resultant peak excitation intensities are 106 times greater than the CW intensities used in confocal microscopy, but the pulse duty cycle of 10−5 limits the average input power to less than 10 mW, only slightly greater than the power normally used in confocal microscopy. Because of the intensity-squared dependence of the two-photon absorption, the excitation is limited to the focal volume.

APA, Harvard, Vancouver, ISO, and other styles

41

Trif, László, Abdul Shaban, and Judit Telegdi. "Electrochemical and surface analytical techniques applied to microbiologically influenced corrosion investigation." Corrosion Reviews 36, no. 4 (July 26, 2018): 349–63. http://dx.doi.org/10.1515/corrrev-2017-0032.

Full text

Abstract:

AbstractSuitable application of techniques for detection and monitoring of microbiologically influenced corrosion (MIC) is crucial for understanding the mechanisms of the interactions and for selecting inhibition and control approaches. This paper presents a review of the application of electrochemical and surface analytical techniques in studying the MIC process of metals and their alloys. Conventional electrochemical techniques, such as corrosion potential (Ecorr), redox potential, dual-cell technique, polarization curves, electrochemical impedance spectroscopy (EIS), electrochemical noise (EN) analysis, and microelectrode techniques, are discussed, with examples of their use in various MIC studies. Electrochemical quartz crystal microbalance, which is newly used in MIC study, is also discussed. Microscopic techniques [scanning electron microscopy (SEM), environmental SEM (ESEM), atomic force microscopy (AFM), confocal laser microscopy (CLM), confocal laser scanning microscopy (CLSM), confocal Raman microscopy] and spectroscopic analytical methods [Fourier transform infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS)] are also highlighted. This review highlights the heterogeneous characteristics of microbial consortia and use of special techniques to study their probable effects on the metal substrata. The aim of this review is to motivate using a combination of new procedures for research and practical measurement and calculation of the impact of MIC and biofilms on metals and their alloys.

APA, Harvard, Vancouver, ISO, and other styles

42

Cheng, Ping-chin. "Current Trends in Digital Imaging for Optical Microscopy." Microscopy and Microanalysis 3, S2 (August 1997): 1097–98. http://dx.doi.org/10.1017/s143192760001237x.

Full text

Abstract:

Digital imaging has provided a number of possibilities in optical microscopy which can not be achieved easily by traditional methods. These include the possibility of low-light imaging, ease of image manipulation (processing and analysis) and transmission via electronic communication channels. Recently, digital imaging has become the buzz-word in photography. Therefore, it is the intent of this article to evaluate the current state of digital imaging technologies for optical microscopy, both pro and con.There are certain applications where digital imaging is the only feasible way to gather image data, examples include laser scanning confocal microscopy and low-light CCD microscopy. Based on the nature of image acquisition methods, one can classify digital imaging into two major domains: (1) sequential and (2) parallel data acquisition. The sequential data acquisition method is generally used in scanning devices such as the confocal laser scanning microscopes (CLSM). Photomultipliers and solid state devices are generally used as the photon detector(s) and the analog signals are subsequently digitized. On the other hand, the use of 2D array detectors such as CCDs falls into the parallel acquisition category. Although, the data from a CCD is read-out sequentially, all the pixels on a CCD chip acquire the image simultaneously. Depending on the dynamic range of the photon detector and needs of the application, the digitized image generally has a dynamic range of 8, 12 or 16 bits.

APA, Harvard, Vancouver, ISO, and other styles

43

Villa, Anna Maria, and Silvia Maria Doglia. "Mitochondria in tumor cells studied by laser scanning confocal microscopy." Journal of Biomedical Optics 9, no. 2 (2004): 385. http://dx.doi.org/10.1117/1.1646414.

Full text

APA, Harvard, Vancouver, ISO, and other styles

44

Thill, A., S. Veerapaneni, B. Simon, M. Wiesner, J. Y. Bottero, and D. Snidaro. "Determination of Structure of Aggregates by Confocal Scanning Laser Microscopy." Journal of Colloid and Interface Science 204, no. 2 (August 1998): 357–62. http://dx.doi.org/10.1006/jcis.1998.5570.

Full text

APA, Harvard, Vancouver, ISO, and other styles

45

Pawley, J. B., and K. Czymmek. "3D Microscopy: Confocal, Deconvolution or Both?" Proceedings, annual meeting, Electron Microscopy Society of America 54 (August 11, 1996): 274–75. http://dx.doi.org/10.1017/s0424820100163836.

Full text

Abstract:

Over the past 20 years great improvements have been made in the techniques available for doing 3D fluorescent microscopy on living cells. The first approach, generally referred to as image deconvolution, treats the stack of 2D widefield (WF) image data as merely the sum of a number of discrete point-spread functions (PSF) and uses the computer to find the array of emitters that, when blurred by the PSF, best fits the stored data. If the PSF is known, only presence of statistical and electronic noise in the data, prevents this best-fit set of emitters from being a perfect image of the dye distribution in the specimen. The crucial role played by noise can be appreciated by comparing images from the Hubbell space telescope in its original condition, even after deconvolution, with images taken after the optics had been repaired.The second approach to 3D microscopy requires the introduction of a confocal aperture in front of the photodetector of a scanning laser microscope so that only the fluorescent signal emitted from the plane-offocus is recorded. As a result the image formed represents an “optical section” and a stack of such sections can be recorded at different focus heights to produce a 3D data set.

APA, Harvard, Vancouver, ISO, and other styles

46

Nie, Shuming, Daniel T. Chiu, and Richard N. Zare. "Real-time observation of single molecules by confocal fluorescence microscopy." Proceedings, annual meeting, Electron Microscopy Society of America 53 (August 13, 1995): 60–61. http://dx.doi.org/10.1017/s0424820100136672.

Full text

Abstract:

The ability to detect, identify, and manipulate individual molecules offer exciting possibilities in many fields, including chemical analysis, materials research, and the biological sciences. A particularly powerful approach is to combine the exquisite sensitivity of laser-induced fluorescence and the spatial localization and imaging capabilities of diffraction-limited or near-field optical microscopes. Unlike scanning tunneling microscopy (STM) and atomic force microscopy (AFM), which lack molecular specificity, optical spectroscopy and microscopy techniques can be used for real-time monitoring and molecular identification at nanometer dimensions or in ultrasmall volumes.We report the use of confocal fluorescence microscopy coupled with a diffraction-limit laser beam and a high-efficiency photodiode for real-time detection of single fluorescent molecules in solution at room temperature. Rigler and Eigen have also demonstrated single-molecule detection with a confocal microscope and fluorescence correlation spectroscopy. The probe (or sampling) volume is effectively an elongated cylinder, with its radius being determined by optical diffraction and length by spherical aberration.

APA, Harvard, Vancouver, ISO, and other styles

47

Stjernström, Mårten, Fredrik Laurell, and Hjalmar Brismar. "Diode-pumped solid state laser light sources for confocal laser scanning fluorescence microscopy." Journal of Laser Applications 20, no. 3 (August 2008): 160–64. http://dx.doi.org/10.2351/1.2955554.

Full text

APA, Harvard, Vancouver, ISO, and other styles

48

Deitch, J. S., D. H. Szarowski, K. L. Smith, J. W. Swann, and J. N. Turner. "Correlative Confocal and Electron Microscopy in Neurobiology." Proceedings, annual meeting, Electron Microscopy Society of America 48, no. 3 (August 12, 1990): 154–55. http://dx.doi.org/10.1017/s0424820100158315.

Full text

Abstract:

We have previously demonstrated the advantages of using confocal scanning laser microscopy (CSLM) in the reflection mode to image neurons labeled with the horseradish peroxidase (HRP) -- diaminobenzidine (DAB) method. Neurons which were impaled with microelectrodes could be characterized electrophysiologically, filled with horseradish peroxidase (or biocytin), reacted with DAB and then imaged in thick section. We have extended this technique to include electron microscopic observations. The optical sections generated with the CSLM helped in localizing specific labeled parts of the tissue that otherwise would require many hours of hunting in order to find.Neurons in 500-μm thick slices of rat hippocampus were filled with HRP via a recording micropipette and fixed for 4 h in 4% paraformaldehyde and 2.5% glutaraldehyde in Ringer’s solution. Vibratome sections were reacted with DAB (1.0 mg/ml) in 0.04% nickel ammonium sulfate, and placed in 1% OsO4 and then in uranyl acetate, each for 1 hour.

APA, Harvard, Vancouver, ISO, and other styles

49

Campagnola, Paul, Aaron Lewis, and Leslie M. Loew. "Second Harmonic Imaging Microscopy: A New Non-Linear Optical Modality for Cell Membrane Physiology." Microscopy and Microanalysis 6, S2 (August 2000): 810–11. http://dx.doi.org/10.1017/s1431927600036540.

Full text

Abstract:

Confocal microscopy is an excellent high resolution method to image fluorescently labeled cells. However, the use of confocal microscopy to monitor physiological events, such as membrane potential changes, in living cells is hampered by photobleaching and phototoxicity. To reduce the collateral damage from excitation of fluorescent probes outside the optical slice, Webb and co-workers introduced the use of two-photon excited (TPE) fluorescence in laser scanning microscopy.1 Two-photon absorption depends on the square of the incident light intensity; this has the effect of confining excitation to the plane of focus where the photon flux density is greatest. The wavelength of the exciting light is in the near infrared facilitating penetration of thick tissues. Due to these significant advantages this methodology is rapidly gaining popularity as a tool for live cell and tissue imaging.To further exploit non-linear optical processes in laser scanning microscopy, we have developed surface second harmonic generation (SHG) as a powerful new imaging modality.

APA, Harvard, Vancouver, ISO, and other styles

50

Amos, William B. "The impact of confocal microscopy in biomedical research." Proceedings, annual meeting, Electron Microscopy Society of America 50, no. 2 (August 1992): 1158–59. http://dx.doi.org/10.1017/s0424820100130420.

Full text

Abstract:

The confocal optical microscope, using laser illumination, has now gained widespread acceptance (see volume edited by Pawley) Its advantage in providing clear optical sections, particularly with fluorescent specimens, is well known. Of the many confocal instruments now in use in cell biology, the applications can be classified into five different categories.The chief use is to give three-dimensional information about conventionally prepared fluorescent specimens. A notable example is the in vivo mapping of an identified neurone through several days of embryonic life by O'Rourke, Scott Fraser and colleagues at Irvine, USA. There has also been much work on in situ hybridisation, morphometry of solid tumours, oncogene product localisation and many aspects of the cytoskeleton.The second use has been in reflection imaging of cell surface contacts, of isolated microtubules and microorganisms, of parts of the eye and of reaction products such as peroxidase.The third application is the measurement of intracellular parameters such as pH and calcium ion concentration within a defined volume.

APA, Harvard, Vancouver, ISO, and other styles

Journal articles on the topic 'Optical polarization and confocal laser microscopy'

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles