Step-by-step guide to reduce spatial coherence of laser light using a rotating ground glass diffuser

Dutch-belted 1 to 2.5 kg anesthetized rabbits were exposed to either xenon or argon laser light administered in a broad band, designed to cover large areas of the retina. For laser exposure, the pupil was dilated with atropine sulfate 1% and pheny lephrine 10%. All of the laser generated power was within a band centered at 5145.0 Anstroms. Established threshold for 4 hour exposures to laser irradiation are in the order of 25-35 microwatts/cm2. Animals examined for ultrastructural changes received 4 hour threshold doses. These animals exhibited ERG, opthalmascopic, and histological changes consistent with threshold damage.One month following exposure the rabbits were killed with pentobarbitol. The eyes were immediately enucleated and dissected while bathed in 3% phosphate buffered gluteraldehyde.

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Quanitative aspects of electron diffraction using electron holography

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139457 ◽

1995 ◽

Vol 53 ◽

pp. 616-617

Author(s):

E. Völkl ◽

L.F. Allard ◽

B. Frost ◽

T.A. Nolan

Keyword(s):

Electron Beam ◽

Electron Diffraction ◽

Software Package ◽

Spatial Coherence ◽

Electron Holography ◽

Image Intensity ◽

Interference Fringes ◽

Complex Image ◽

The Difference ◽

Recorded Image

Off-axis electron holography has the well known ability to preserve the complex image wave within the final, recorded image. This final image described by I(x,y) = I(r) contains contributions from the image intensity of the elastically scattered electrons IeI (r) = |A(r) exp (iΦ(r)) |, the contributions from the inelastically scattered electrons IineI (r), and the complex image wave Ψ = A(r) exp(iΦ(r)) as:(1) I(r) = IeI (r) + Iinel (r) + μ A(r) cos(2π Δk r + Φ(r))where the constant μ describes the contrast of the interference fringes which are related to the spatial coherence of the electron beam, and Φk is the resulting vector of the difference of the wavefront vectors of the two overlaping beams. Using a software package like HoloWorks, the complex image wave Ψ can be extracted.

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Estimation of the noise in TEM image recorded on “imaging plate”

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100128055 ◽

1987 ◽

Vol 45 ◽

pp. 748-749

Author(s):

T. Oikawa ◽

N. Mori ◽

T. Katoh ◽

Y. Harada ◽

J. Miyahara ◽

...

Keyword(s):

Low Dose ◽

Quantum Noise ◽

Laser Light ◽

Imaging Plate ◽

Total System ◽

Electron Dose ◽

X Ray ◽

Image Recording ◽

Recording Material ◽

Highly Sensitive

The “Imaging Plate”(IP) is a highly sensitive image recording plate for X-ray radiography. It has been ascertained that the IP has superior properties and high practicability as an image recording material in a TEM. The sensitivity, one of the properties, is about 3 orders higher than that of conventional photo film. The IP is expected to be applied to low dose techniques. In this paper, an estimation of the quantum noise on the TEM image which appears in case of low electron dose on the IP is reported.In this experiment, the JEM-2000FX TEM and an IP having the same size as photo film were used.Figure 1 shows the schematic diagram of the total system including the TEM used in this experiment. In the reader, He-Ne laser light is scanned across the IP, then blue light is emitted from the IP.

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The influence of temporal and spatial coherence on object representations

PsycEXTRA Dataset ◽

10.1037/e536982012-018 ◽

1997 ◽

Author(s):

Ken Seergobin ◽

Steve Joordens

Keyword(s):

Spatial Coherence ◽

Object Representations ◽

Temporal And Spatial

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