42,581 research outputs found
Axial plane optical microscopy.
We present axial plane optical microscopy (APOM) that can, in contrast to conventional microscopy, directly image a sample's cross-section parallel to the optical axis of an objective lens without scanning. APOM combined with conventional microscopy simultaneously provides two orthogonal images of a 3D sample. More importantly, APOM uses only a single lens near the sample to achieve selective-plane illumination microscopy, as we demonstrated by three-dimensional (3D) imaging of fluorescent pollens and brain slices. This technique allows fast, high-contrast, and convenient 3D imaging of structures that are hundreds of microns beneath the surfaces of large biological tissues
Towards the 3D-Imaging of Sources
Geometric details of a nuclear reaction zone, at the time of particle
emission, can be restored from low relative-velocity particle-correlations,
following imaging. Some of the source details get erased and are a potential
cause of problems in the imaging, in the form of instabilities. These can be
coped with by following the method of discretized optimization for the restored
sources. So far it has been possible to produce 1-dimensional emission source
images, corresponding to the reactions averaged over all possible spatial
directions. Currently, efforts are in progress to restore angular details.Comment: Talk given at the Int. Workshop on Hot and Dense Matter in
Relativistic Heavy Ion Collisions, March 24-27, 2004, Budapest; 10 pages, 6
figure
3D Imaging of a Phase Object from a Single Sample Orientation Using an Optical Laser
Ankylography is a new 3D imaging technique, which, under certain
circumstances, enables reconstruction of a 3D object from a single sample
orientation. Here, we provide a matrix rank analysis to explain the principle
of ankylography. We then present an ankylography experiment on a microscale
phase object using an optical laser. Coherent diffraction patterns are acquired
from the phase object using a planar CCD detector and are projected onto a
spherical shell. The 3D structure of the object is directly reconstructed from
the spherical diffraction pattern. This work may potentially open the door to a
new method for 3D imaging of phase objects in the visible light region.
Finally, the extension of ankylography to more complicated and larger objects
is suggested.Comment: 22 pages 5 figure
Spectroscopy and 3D imaging of the Crab nebula
Spectroscopy of the Crab nebula along different slit directions reveals the 3
dimensional structure of the optical nebula. On the basis of the linear radial
expansion result first discovered by Trimble (1968), we make a 3D model of the
optical emission. Results from a limited number of slit directions suggest that
optical lines originate from a complicated array of wisps that are located in a
rather thin shell, pierced by a jet. The jet is certainly not prominent in
optical emission lines, but the direction of the piercing is consistent with
the direction of the X-ray and radio jet. The shell's effective radius is ~ 79
seconds of arc, its thickness about a third of the radius and it is moving out
with an average velocity 1160 km/s.Comment: 21 pages, 14 figures, submitted to ApJ, 3D movie of the Crab nebula
available at http://www.fiz.uni-lj.si/~vidrih
Single exposure 3D imaging of dusty plasma clusters
We have worked out the details of a single camera, single exposure method to
perform three-dimensional imaging of a finite particle cluster. The procedure
is based on the plenoptic imaging principle and utilizes a commercial Lytro
light field still camera. We demonstrate the capabilities of our technique on a
single layer particle cluster in a dusty plasma, where the camera is aligned
inclined at a small angle to the particle layer. The reconstruction of the
third coordinate (depth) is found to be accurate and even shadowing particles
can be identified.Comment: 6 pages, 7 figures. Submitted to Rev. Sci. Inst
3D Imaging of Gems and Minerals by Multiphoton Microscopy
Many optical approaches have been used to examine the composition and
structure of gemstones, both recently and throughout history. The nonlinear
optical behavior of different gemstones has not been investigated, and the
higher order terms to the refractive index represent an unused tool for
qualifying and examining a stone. We have used a multiphoton microscope to
examine the nonlinear optical properties of 36 different gemstones and
demonstrate that it is a useful tool for imaging them three-dimensionally up to
the millimeter scale below the sample surface. The polarization dependence of
second harmonic generation signals was used to examine the crystal orientations
inside the minerals.Comment: 9 pages, five figure
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