A simple method reconstructing colorful holographic imaging with GPU acceleration based on one thin phase plate

The following are the main improvements that we have made in the method of phase-contrast microscopy described by Kempson, Thomas, and Baker (1948): 1. No bull's-eye condenser is used. The illuminant is an electric bulb with a ‘porcelain-processed’, ‘flashed white’, or ‘opal’ surface. 2. No oiled paper is placed over the illuminating annulus. 3. The thickness of the deposit of magnesium fluoride on the phase-plate is controlled by observations on the interference colours given by surface reflections. 4. Positive (dark) phase-contrast is preferred for most purposes to negative (bright).

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Simple method to enhance terahertz radiation from femtosecond laser filament array with a step phase plate

Optics Letters ◽

10.1364/ol.40.003838 ◽

2015 ◽

Vol 40 (16) ◽

pp. 3838 ◽

Cited By ~ 14

Author(s):

Jiayu Zhao ◽

Lanjun Guo ◽

Wei Chu ◽

Bin Zeng ◽

Hui Gao ◽

...

Keyword(s):

Femtosecond Laser ◽

Terahertz Radiation ◽

Phase Plate ◽

Simple Method

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A Simple Method for Phase-Contrast Microscopy

Journal of Cell Science ◽

10.1242/jcs.s3-89.7.351 ◽

1948 ◽

Vol s3-89 (7) ◽

pp. 351-358

Author(s):

D. A. KEMPSON ◽

O. L. THOMAS ◽

JOHN R. BAKER

Keyword(s):

Phase Contrast ◽

Phase Plate ◽

Phase Contrast Microscopy ◽

Simple Method ◽

Contrast Microscopy ◽

Annular Source

A method of phase-contrast microscopy is described, not involving the use of special objectives or condensers. A method for making the phase-plate carrying a raised annulus is described. A large annular source of light is focused by the condenser of the microscope in a plane slightly below the object. The phase-plate is placed in the conjugate focus of this plane, just above the back lens of the objective.

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Characteristics of an Electrostatic Phase Plate

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100096345 ◽

1972 ◽

Vol 30 ◽

pp. 618-619

Author(s):

William Krakow ◽

Benjamin Siegel

Keyword(s):

Phase Contrast ◽

Objective Lens ◽

Phase Plate ◽

Net Charge ◽

Phase Plates ◽

Beam Currents ◽

Contrast Image ◽

Bright Phase ◽

Additional Phase Shift ◽

Additional Phase

Unwin has used a metallized non-conducting thread in the back focal plane of the objective lens that stops out a portion of the unscattered beam, takes on a localized positive charge and thus produces an additional phase shift to give a different transfer function of the lens. Under the particular conditions Unwin used, the phase contrast image was shifted to bright phase contrast for optimum focus.We have investigated the characteristics of this type of electrostatic phase plate, both analytically and experimentally, as functions of the magnitude of charge and defocus. Phase plates have been constructed by using Wollaston wire to mount 0.25μ diameter platinum wires across apertures ranging from 50 to 200μ diameter and vapor depositing SiO and gold on the mounted wires to give them the desired charging characteristics. The net charge was varied by adjusting only the bias on the Wehnelt shield of the gun, and hence the beam currents and effective size of the source.

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A simple way for producing holographic filters suitable for image improvement

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100108271 ◽

1978 ◽

Vol 36 (1) ◽

pp. 226-227

Author(s):

K.-H. Herrmann ◽

E. Reuber ◽

P. Schiske

Keyword(s):

Transfer Functions ◽

Diffraction Order ◽

Lateral Position ◽

Simple Method ◽

Spatial Frequencies ◽

Resolution Electron ◽

Wiener Filters ◽

Image Improvement ◽

Optical Reconstruction ◽

Set Up

Aposteriori deblurring of high resolution electron micrographs of weak phase objects can be performed by holographic filters [1,2] which are arranged in the Fourier domain of a light-optical reconstruction set-up. According to the diffraction efficiency and the lateral position of the grating structure, the filters permit adjustment of the amplitudes and phases of the spatial frequencies in the image which is obtained in the first diffraction order.In the case of bright field imaging with axial illumination, the Contrast Transfer Functions (CTF) are oscillating, but real. For different imageforming conditions and several signal-to-noise ratios an extensive set of Wiener-filters should be available. A simple method of producing such filters by only photographic and mechanical means will be described here.A transparent master grating with 6.25 lines/mm and 160 mm diameter was produced by a high precision computer plotter. It is photographed through a rotating mask, plotted by a standard plotter.

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Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099192 ◽

1981 ◽

Vol 39 ◽

pp. 550-551

Author(s):

Dean A. Handley ◽

Jack T. Alexander ◽

Shu Chien

Keyword(s):

Cell Growth ◽

Cell Cultures ◽

Molecular Interactions ◽

Convenient Method ◽

Petri Dish ◽

Simple Method ◽

Thin Section Microscopy ◽

Thin Sectioning ◽

Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

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Performance and applications of the holography electron microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100151222 ◽

1993 ◽

Vol 51 ◽

pp. 1078-1079

Author(s):

Akira Tonomura

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Phase Measurement ◽

Electron Holography ◽

Imaging Method ◽

High Contrast ◽

Magnetic Lens ◽

High Brightness ◽

Holographic Imaging ◽

Dynamic Observation

Electron holography is a two-step imaging method. However, the ultimate performance of holographic imaging is mainly determined by the brightness of the electron beam used in the hologram-formation process. In our 350kV holography electron microscope (see Fig. 1), the decrease in the inherently high brightness of field-emitted electrons is minimized by superposing a magnetic lens in the gun, for a resulting value of 2 × 109 A/cm2 sr. This high brightness has lead to the following distinguished features. The minimum spacing (d) of carrier fringes is d = 0.09 Å, thus allowing a reconstructed image with a resolution, at least in principle, as high as 3d=0.3 Å. The precision in phase measurement can be as high as 2π/100, since the position of fringes can be known precisely from a high-contrast hologram formed under highly collimated illumination. Dynamic observation becomes possible because the current density is high.

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