4,638 research outputs found
Cavlectometry: Towards Holistic Reconstruction of Large Mirror Objects
We introduce a method based on the deflectometry principle for the
reconstruction of specular objects exhibiting significant size and geometric
complexity. A key feature of our approach is the deployment of an Automatic
Virtual Environment (CAVE) as pattern generator. To unfold the full power of
this extraordinary experimental setup, an optical encoding scheme is developed
which accounts for the distinctive topology of the CAVE. Furthermore, we devise
an algorithm for detecting the object of interest in raw deflectometric images.
The segmented foreground is used for single-view reconstruction, the background
for estimation of the camera pose, necessary for calibrating the sensor system.
Experiments suggest a significant gain of coverage in single measurements
compared to previous methods. To facilitate research on specular surface
reconstruction, we will make our data set publicly available
Shape reconstruction from gradient data
We present a novel method for reconstructing the shape of an object from
measured gradient data. A certain class of optical sensors does not measure the
shape of an object, but its local slope. These sensors display several
advantages, including high information efficiency, sensitivity, and robustness.
For many applications, however, it is necessary to acquire the shape, which
must be calculated from the slopes by numerical integration. Existing
integration techniques show drawbacks that render them unusable in many cases.
Our method is based on approximation employing radial basis functions. It can
be applied to irregularly sampled, noisy, and incomplete data, and it
reconstructs surfaces both locally and globally with high accuracy.Comment: 16 pages, 5 figures, zip-file, submitted to Applied Optic
Planar Airy beam light-sheet for two-photon microscopy
We demonstrate the first planar Airy light-sheet microscope. Fluorescence
light-sheet microscopy has become the method of choice to study large
biological samples with cellular or sub-cellular resolution. The
propagation-invariant Airy beam enables a ten-fold increase in field-of-view
with single-photon excitation; however, the characteristic asymmetry of the
light-sheet limits its potential for multi-photon excitation. Here we show how
a planar light-sheet can be formed from the curved propagation-invariant Airy
beam. The resulting symmetric light sheet excites two-photon fluorescence
uniformly across an extended field-of-view without the need for deconvolution.
We demonstrate the method for rapid two-photon imaging of large volumes of
neuronal tissue.Comment: 7 pages, 4 figure
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