Polarization neutral point pairs of the solar corona and the lunar disc observed during the total solar eclipse on 11 August 1999 in Hungary.

During the total solar eclipses on 11 August 1999 in Kecel (Hungary) and on 29 March 2006 in Side (Turkey), two Hungarian groups performed full-sky imaging polarimetric measurements of the eclipsed sky. They observed the spatiotemporal change of the celestial polarization pattern and detected three polarization neutral points as well as two points with maximal polarization of the sky. Parallel to these studies, the polarization pattern in front of the lunar disc, the solar corona, and the surrounding sky have also been measured.

Mapping microscopic order in plant and mammalian cells and tissues: novel differential polarization attachment for new generation confocal microscopes (DP-LSM).

Elucidation of the molecular architecture of complex, highly organized molecular macro-assemblies is an important, basic task for biology. Differential polarization (DP) measurements, such as linear (LD) and circular dichroism (CD) or the anisotropy of the fluorescence emission (r), which can be carried out in a dichrograph or spectrofluorimeter, respectively, carry unique, spatially averaged information about the molecular organization of the sample. For inhomogeneous samples-e.

On the trail of Vikings with polarized skylight: experimental study of the atmospheric optical prerequisites allowing polarimetric navigation by Viking seafarers.

Between AD 900 and AD 1200 Vikings, being able to navigate skillfully across the open sea, were the dominant seafarers of the North Atlantic. When the Sun was shining, geographical north could be determined with a special sundial. However, how the Vikings could have navigated in cloudy or foggy situations, when the Sun's disc was unusable, is still not fully known.

Confocal fluorescence detected linear dichroism imaging of isolated human amyloid fibrils. Role of supercoiling.

Amyloids are highly organized insoluble protein aggregates that are associated with a large variety of degenerative diseases. In this work, we investigated the anisotropic architecture of isolated human amyloid samples stained with Congo Red. This was performed by fluorescence detected linear dichroism (FDLD) imaging in a laser scanning confocal microscope that was equipped with a differential polarization attachment using high frequency modulation of the polarization state of the laser beam and a demodulation circuit.

Imaging anisotropy using differential polarization laser scanning confocal microscopy.

We have constructed differential polarization (DP) attachments to a laser scanning microscope (LSM) for imaging the main DP quantities of anisotropic microscopic objects. The DP-LSM operates with high-frequency modulation and subsequent demodulation and displays the main DP quantities pixel by pixel. These, for linearly polarized light, include: (i) linear birefringence (LB), which is exhibited by structurally and/or optically anisotropic material; (ii) linear dichroism (LD), which carries information on the anisotropic distribution of the molecules, i.