Redistribution of Information for Imaging Systems with Increasing Numerical Aperture

AbstractSurface plasmons are highly sensitive to refractive index variations adjacent to the surface. This sensitivity has been exploited successfully for chemical and biological assays. In these systems, a surface plasmon resonance (SPR)-based sensor detects temporal variations in the refractive index at a point. SPR has also been used in imaging systems where the spatial variations of refractive index in the sample provide the contrast mechanism. A high numerical aperture objective lens has been used to design SPR microscopy systems with the ability to image adherent live cells. Addressing research questions in cell physiology and pharmacology often requires the development of a multimodal microscope where complementary information can be obtained.In this paper, we present the development of a multimodal microscope that combines surface plasmon resonance imaging with a number of additional imaging modalities including bright-field, epi-fluorescence, total internal reflection microscopy (TIRM) and SPR fluorescence microscopy. We used a high numerical aperture objective lens to achieve SPR and TIR microscopy with the ability to image adherent live cells non-invasively. The platform has been used to image live cell cultures demonstrating both fluorescent and label-free techniques. The SPR and TIR imaging systems feature a wide field of view (300 µm) that allows measurements from multiple cells while the resolution is sufficient to image fine cellular processes. The ability of the platform to perform label-free functional imaging of living cell was demonstrated by imaging the spatial variations in contraction of stem cell-derived cardiomyocytes. This technique has a promise for non-invasive imaging of the development of cultured cells over very long periods of time.

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High-NA open-top selective-plane illumination microscopy for biological imaging

10.1101/140418 ◽

2017 ◽

Author(s):

Ryan McGorty ◽

Dan Xie ◽

Bo Huang

Keyword(s):

Adaptive Optics ◽

Biological Sample ◽

Spatial Configuration ◽

Numerical Aperture ◽

Biological Imaging ◽

Imaging Systems ◽

Optical Components ◽

Volumetric Imaging ◽

Selective Plane Illumination Microscopy ◽

Living Organisms

Abstract:Selective-plane illumination microscopy (SPIM) provides unparalleled advantages for volumetric imaging of living organisms over extended times. However, the spatial configuration of a SPIM system often limits its compatibility with many widely used biological sample holders such as multi-well chambers and plates. To solve this problem, we developed a high numerical aperture (NA) open-top configuration that places both the excitation and detection objectives on the opposite of the sample coverglass. We carried out a theoretical calculation to analyze the structure of the system-induced aberrations. We then experimentally compensated the system aberrations using adaptive optics combined with static optical components, demonstrating near-diffraction-limited performance in imaging fluorescently labeled cells.© 2017 Optical Society of AmericaOCIS codes: (080.080) Geometric Optics; (110.0110) Imaging systems; (110.0180) Microscopy.

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High numerical aperture imaging systems formed by integrating bionic artificial compound eyes on a CMOS sensor

Optical Materials Express ◽

10.1364/ome.427623 ◽

2021 ◽

Author(s):

yueqi zhai ◽

Jiaqi Niu ◽

Jing Liu ◽

Bin Yang

Keyword(s):

Numerical Aperture ◽

Imaging Systems ◽

Compound Eyes ◽

High Numerical Aperture ◽

Cmos Sensor

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Flat optics in high numerical aperture broadband imaging systems

Journal of Optics ◽

10.1088/2040-8986/ab8ea2 ◽

2020 ◽

Vol 22 (6) ◽

pp. 065607 ◽

Cited By ~ 3

Author(s):

Daniel Werdehausen ◽

Sven Burger ◽

Isabelle Staude ◽

Thomas Pertsch ◽

Manuel Decker

Keyword(s):

Numerical Aperture ◽

Imaging Systems ◽

High Numerical Aperture

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Video-Enhanced Microscopy--Better Visibility of Plant Cell Structures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100053589 ◽

1982 ◽

Vol 40 ◽

pp. 182-185

Author(s):

N.S. Allen ◽

R.D. Allen

Keyword(s):

Diffraction Pattern ◽

Theoretical Basis ◽

Numerical Aperture ◽

Gain Control ◽

Control Unit ◽

Camera Control ◽

Variable Gain ◽

Contrast Method ◽

Fine Detail ◽

Cell Structures

Various methods of video-enhanced microscopy combine TV cameras with light microscopes creating images with improved resolution, contrast and visibility of fine detail, which can be recorded rapidly and relatively inexpensively. The AVEC (Allen Video-enhanced Contrast) method avoids polarizing rectifiers, since the microscope is operated at retardations of λ/9- λ/4, where no anomaly is seen in the Airy diffraction pattern. The iris diaphram is opened fully to match the numerical aperture of the condenser to that of the objective. Under these conditions, no image can be realized either by eye or photographically. Yet the image becomes visible using the Hamamatsu C-1000-01 binary camera, if the camera control unit is equipped with variable gain control and an offset knob (which sets a clamp voltage of a D.C. restoration circuit). The theoretical basis for these improvements has been described.

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Digital imaging and quantitative image analysis of polymer blends

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100163319 ◽

1996 ◽

Vol 54 ◽

pp. 170-171

Author(s):

Xiao Zhang

Keyword(s):

Digital Imaging ◽

Imaging Techniques ◽

Imaging Systems ◽

Polymer Science ◽

Key Factors ◽

Multiple Imaging ◽

Quantitative Image ◽

Digital Imaging Systems ◽

Multi Phase ◽

Network Technologies

Polymer microscopy involves multiple imaging techniques. Speed, simplicity, and productivity are key factors in running an industrial polymer microscopy lab. In polymer science, the morphology of a multi-phase blend is often the link between process and properties. The extent to which the researcher can quantify the morphology determines the strength of the link. To aid the polymer microscopist in these tasks, digital imaging systems are becoming more prevalent. Advances in computers, digital imaging hardware and software, and network technologies have made it possible to implement digital imaging systems in industrial microscopy labs.

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On resolving fine periodic microstructures in the optical microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100153798 ◽

1989 ◽

Vol 47 ◽

pp. 364-365

Author(s):

W.S. Putnam ◽

C. Viney

Keyword(s):

Liquid Crystalline ◽

Numerical Aperture ◽

Polarized Light ◽

Normal Incidence ◽

Optical Microscope ◽

Angle Of Incidence ◽

Resolution Limit ◽

Crystalline Materials ◽

Periodic Microstructures ◽

Liquid Crystalline Materials

Many sheared liquid crystalline materials (fibers, films and moldings) exhibit a fine banded microstructure when observed in the polarized light microscope. In some cases, for example Kevlar® fiber, the periodicity is close to the resolution limit of even the highest numerical aperture objectives. The periodic microstructure reflects a non-uniform alignment of the constituent molecules, and consequently is an indication that the mechanical properties will be less than optimal. Thus it is necessary to obtain quality micrographs for characterization, which in turn requires that fine detail should contribute significantly to image formation.It is textbook knowledge that the resolution achievable with a given microscope objective (numerical aperture NA) and a given wavelength of light (λ) increases as the angle of incidence of light at the specimen surface is increased. Stated in terms of the Abbe resolution criterion, resolution improves from λ/NA to λ/2NA with increasing departure from normal incidence.

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Performance Evaluation of a Novel Type of Low-Energy Electron Microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100180525 ◽

1990 ◽

Vol 48 (1) ◽

pp. 354-355

Author(s):

Bertholdand Senftinger ◽

Helmut Liebl

Keyword(s):

Electron Microscope ◽

High Resolution ◽

Field Strength ◽

Numerical Aperture ◽

Low Energy ◽

Energy Electron ◽

High Resolution Imaging ◽

Lens System ◽

Resolution Imaging ◽

Low Energy Electron

During the last few years the investigation of clean and adsorbate-covered solid surfaces as well as thin-film growth and molecular dynamics have given rise to a constant demand for high-resolution imaging microscopy with reflected and diffracted low energy electrons as well as photo-electrons. A recent successful implementation of a UHV low-energy electron microscope by Bauer and Telieps encouraged us to construct such a low energy electron microscope (LEEM) for high-resolution imaging incorporating several novel design features, which is described more detailed elsewhere.The constraint of high field strength at the surface required to keep the aberrations caused by the accelerating field small and high UV photon intensity to get an improved signal-to-noise ratio for photoemission led to the design of a tetrode emission lens system capable of also focusing the UV light at the surface through an integrated Schwarzschild-type objective. Fig. 1 shows an axial section of the emission lens in the LEEM with sample (28) and part of the sample holder (29). The integrated mirror objective (50a, 50b) is used for visual in situ microscopic observation of the sample as well as for UV illumination. The electron optical components and the sample with accelerating field followed by an einzel lens form a tetrode system. In order to keep the field strength high, the sample is separated from the first element of the einzel lens by only 1.6 mm. With a numerical aperture of 0.5 for the Schwarzschild objective the orifice in the first element of the einzel lens has to be about 3.0 mm in diameter. Considering the much smaller distance to the sample one can expect intense distortions of the accelerating field in front of the sample. Because the achievable lateral resolution depends mainly on the quality of the first imaging step, careful investigation of the aberrations caused by the emission lens system had to be done in order to avoid sacrificing high lateral resolution for larger numerical aperture.

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