How to separate linear birefringence from linear biextinction (linear dichroism) with the polarized light microscope

We reported magnetooptical properties of Tb3+in single crystals of Tb3Fe5O12and Tb3Ga5O12for ion occupying sites of D2symmetry in the garnets structure. It is shown that in the employed Voigt geometry the magnetic linear birefringence and the dichroism reach values 10-4, and have a strong dependence on the wavelength and a strong anisotropy. The absorption spectra were obtained at temperatures of 30K, 100K using magnetic field up to 25 kOe applied parallel and perpendiculare to the electric vector E linearly polarized light on the7F67F0and7F67F1optical transitions region. The aim of this research was revealing of a role of contributions of exchange interaction and a crystal field in splitting of energy levels of the basic condition7F6ion Tb3+multiplet in Tb ferrite-garnet by studying of character of spectra magnetic linear dichroism (MLD) paramagnetic and ferrimagnetic crystals placed in an external magnetic field. More over, the assumption about nonreciprocity of magnetic linear birefringence (MLB) spectra and dichroism with the change of the relative orientation of the magnetization vector I and the light wave vector has been experimentally confirmed. This effect may use as a base for the design of the different transducers, for example, magnetooptical optical channels commutator.

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Anisotropy of the Linear Magnetic Birefridence of Europium Iron Garnet

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.605.548 ◽

2014 ◽

Vol 605 ◽

pp. 548-552

Author(s):

Natalia Tsidaeva ◽

Viktorija Abaeva ◽

Anatoly Turiev ◽

Elena Enaldieva ◽

Tengiz Butkhuzi ◽

...

Keyword(s):

Single Crystal ◽

Polarized Light ◽

Magnetization Vector ◽

Linear Dichroism ◽

Linear Birefringence ◽

Optical Channels ◽

Iron Garnets ◽

Linearly Polarized ◽

Magnetic Linear Dichroism ◽

Iron Garnet

The results of investigation of magnetic linear birefringence (MLB) and magnetic linear dichroism (MLD) of Eu3Fe5O12(EuIG) iron garnet on7F07F6optical transitions upon variation of the directions of the magnetization vector I relative to the electric vector E linearly polarized light that propagates through single crystal iron garnets are presented. The measurements were made on Eu3Fe5O12single-crystal samples in the form of plates 100 μm thick cut in the (110) and (100) plane at the temperatures T = 82 and in a magnetic field H= 25 kOe. The absorption spectra of the linearly polarized light were studied. It is shown that MLB and dichroism in the region of the7F07F6absorption band reach values 10-3. First experimentally discovered nonreciprocity of MLB spectra and dichroism with the change of the relative orientation of the magnetization vector I and the light wave vector. This effect may use as a base for the design of the different transducers, for example, magnetooptical optical channels commutator.

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High-resolution measurement of birefringent fine structure in living cells using a new polarized light microscope

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100136647 ◽

1995 ◽

Vol 53 ◽

pp. 54-55

Author(s):

Rudolf Oldenbourg

Keyword(s):

Light Microscope ◽

Fluorescent Dyes ◽

Polarized Light ◽

Processing System ◽

Video Camera ◽

Molecular Organization ◽

Computer Assisted ◽

Image Recording ◽

Birefringent Crystal ◽

Technological Advances

The recent renaissance of the light microsope is fueled in part by technological advances in components on the periphery of the microscope, such as the laser as illumination source, electronic image recording (video), computer assisted image analysis and the biochemistry of fluorescent dyes for labeling specimens. After great progress in these peripheral parts, it seems timely to examine the optics itself and ask how progress in the periphery facilitates the use of new optical components and of new optical designs inside the microscope. Some results of this fruitful reflection are presented in this symposium.We have considered the polarized light microscope, and developed a design that replaces the traditional compensator, typically a birefringent crystal plate, with a precision universal compensator made of two liquid crystal variable retarders. A video camera and digital image processing system provide fast measurements of specimen anisotropy (retardance magnitude and azimuth) at ALL POINTS of the image forming the field of view. The images document fine structural and molecular organization within a thin optical section of the specimen.

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New polarized-light microscope for fast and orientation independent measurement of birefringent fine structure

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100146254 ◽

1993 ◽

Vol 51 ◽

pp. 82-83

Author(s):

Rudolf Oldenbourg

Keyword(s):

Light Microscope ◽

Polarized Light ◽

Video Camera ◽

Limited Range ◽

Image Point ◽

Computer Assisted ◽

Optical Modulators ◽

Anisotropic Structures ◽

Long Time ◽

Computer Assisted Image

The polarized light microscope has the unique potential to measure submicroscopic molecular arrangements dynamically and non-destructively in living cells and other specimens. With the traditional pol-scope, however, single images display only those anisotropic structures that have a limited range of orientations with respect to the polarization axes of the microscope. Furthermore, rapid measurements are restricted to a single image point or single area that exhibits uniform birefringence or other form of optical anisotropy, while measurements comparing several image points take an inordinately long time.We are developing a new kind of polarized light microscope which combines speed and high resolution in its measurement of the specimen anisotropy, irrespective of its orientation. The design of the new pol-scope is based on the traditional polarized light microscope with two essential modifications: circular polarizers replace linear polarizers and two electro-optical modulators replace the traditional compensator. A video camera and computer assisted image analysis provide measurements of specimen anisotropy in rapid succession for all points of the image comprising the field of view.

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Light microscopy of ceramics

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010015037x ◽

1993 ◽

Vol 51 ◽

pp. 908-909

Author(s):

Walter C. McCrone

Keyword(s):

Refractive Index ◽

Light Microscopy ◽

Light Microscope ◽

Polarized Light ◽

Refractive Indices ◽

Complete Coverage ◽

The Subject ◽

Lower Refractive Index

An excellent chapter on this subject by V.D. Fréchette appeared in a book edited by L.L. Hench and R.W. Gould in 1971 (1). That chapter with the references cited there provides a very complete coverage of the subject. I will add a more complete coverage of an important polarized light microscope (PLM) technique developed more recently (2). Dispersion staining is based on refractive index and its variation with wavelength (dispersion of index). A particle of, say almandite, a garnet, has refractive indices of nF = 1.789 nm, nD = 1.780 nm and nC = 1.775 nm. A Cargille refractive index liquid having nD = 1.780 nm will have nF = 1.810 and nC = 1.768 nm. Almandite grains will disappear in that liquid when observed with a beam of 589 nm light (D-line), but it will have a lower refractive index than that liquid with 486 nm light (F-line), and a higher index than that liquid with 656 nm light (C-line).

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Study on the Crystalline Morphology of HDPE/E-TMB Blends

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.200.406 ◽

2012 ◽

Vol 200 ◽

pp. 406-410

Author(s):

Wei Hua Fan ◽

Ren Jie Wang ◽

Yu Kun Liu ◽

Kai Guo ◽

Jin Zhou Chen ◽

...

Keyword(s):

Crystallite Size ◽

Light Microscope ◽

Polarized Light ◽

Crystalline Morphology ◽

Master Batch

HE1/E-TMB and HE2/E-TMB blends are prepared by thermal mechanical blending of toughening master batch (E-TMB) with 2200JHDPE (HE1) and 5000SHDPE (HE2), respectively. The crystalline morphology of HE1/E-TMB and HE2/E-TMB blends were studied with polarized light microscope (PLM), and compared with those of HE1/E-SMB and HE2/E-SMB blends. The results showed that the crystallite size of HDPE/E-TMB and HE/E-SMB blends was remarkably smaller than that of the pure HDPE, while the number of the crystals increased. At the same elastomer content, the refined extend of the crystallite of HE2/E-TMB blends obviously increased than that of the HE1/E-TMB blends. The number of the crystal gradually increased and the crystallite size substantially reduced with the elastomers ratio (M/N) increasing. The refined extend of the crystallite of HDPE/E-TMB blends gradually enhanced and the number of the crystal substantially increased as the elastomer content gradually growing.

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