Improved superresolution in coherent optical systems.
Objects that temporally vary slowly can be superresolved by the use of two synchronized moving masks such as pinholes or gratings. This approach to superresolution allows one to exceed Abbe\’s limit of resolution. Moreover, under coherent illumination, superresolution requires a certain approximation based on the time averaging […]

read more from this topic.....

Nonlinear correlation for estimating the motion of multiple objects in image sequences.
A nonlinear correlation algorithm is proposed for estimating the motion of objects from an image pair. This algorithm requires no a priori information on the number, size, or shape of the moving objects and does not require feature extraction or segmentation […]

read more from this topic.....

Resolution analysis of incoherent triangular holography.
We derived the point-spread function (PSF) including the recording and reconstruction systems of the modified triangular interferometer; the modified triangular interferometer forms incoherent holograms without bias and the conjugate image. We also derived and analyzed the resolution of the modified triangular interferometer and compared it with that […]

read more from this topic.....

Holographic recording with orthogonally polarized beams in a cesium-doped (k(0.5)na(0.5))(0.2)(sr(0.75)ba(0.25))(0.9)nb(2)o(6) crystal.
Holographic recording with orthogonally polarized beams in a cesium-doped KNSBN [(K(0.5)Na(0.5))(0.2)(Sr(0.75)Ba(0.25))(0.9)Nb(2)O(6)] crystal has been studied. It was found that this kind of photorefractive crystal possesses high linear dichroism, which makes it suitable for use in polarization holography. The diffraction efficiency as a […]

read more from this topic.....

Projection-invariant pattern recognition with logarithmic harmonic function and wavelet transform.
A logarithmic harmonic filter can detect objects at different projection angles. The Mexican-hat wavelet function can extract edges of equal width for objects, regardless of their sizes. Hence incorporating wavelet filtering in the logarithmic harmonic filter can improve its performance. The theory is […]

read more from this topic.....

One-step measurement of optical fields in multimode circular fibers.
We propose to determine the optical field in multimode circular fibers by using a one-step method that measures the Wigner distribution function of a section of the field in the fiber. This method allows an estimation not only of the power carried by each […]

read more from this topic.....

Intrinsic fluorescence spectroscopy in turbid media: disentangling effects of scattering and absorption.
The fluorescence from a turbid medium such as biologic tissue contains information about scattering and absorption, as well as the intrinsic fluorescence, i.e., the fluorescence from an optically thin sample of pure fluorophores. The interplay of scattering and absorption can result […]

read more from this topic.....

Accuracy of a perturbation model to predict the effect of scattering and absorbing inhomogeneities on photon migration.
The accuracy of the perturbation model to predict the effect of scattering and absorbing inhomogeneities on photon migration has been investigated by comparisons with experimental and numerical results. Comparisons for scattering inhomogeneities showed that the model […]

read more from this topic.....

Absorbance of opaque microstructures in optically diffuse media.
In this study experimental measurements are used to determine that the observed absorbance of opaque microstructures in optically diffuse media correlates with the total surface area rather than the attenuation as calculated in a nonscattering environment. The data suggest that it may be possible to […]

read more from this topic.....

Self-mixing feedback in a laser diode for intra-arterial optical blood velocimetry.
Intra-arterial measurements of the velocity and the average flow of red-blood cells were investigated by means of a fiber-coupled laser Doppler velocimeter based on the self-mixing effect. The velocity of the red cells was calculated from the frequency of the signal that […]

read more from this topic.....