A method of measuring the refractive index of extraordinary ray in uniaxial crystal with optic axis at an arbitrary orientation

A linear relation has been established between the plane of focus for schlieren optics in the ultracentrifuge cell along the optic axis, and the refractive index of the liquid contained in the cell. Such a relation shows that there occurs a defocussing effect when a large change in refractive index is generated in the liquid column during centrifugation of multi-component systems.

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Birefrince Characteristics of an Optical Element

International Journal of Innovative Technology and Exploring Engineering - Special Issue ◽

10.35940/ijitee.i3166.0789s319 ◽

2019 ◽

Vol 8 (9S3) ◽

pp. 801-803

Keyword(s):

Phase Difference ◽

Optical Element ◽

Uniaxial Crystal ◽

Optic Axis ◽

Intensity Measurement ◽

Double Refraction ◽

Varying Thickness

Phase difference variation in uniaxial crystal is investigated for varying thickness. Using double refraction property and optic axis method leads to the intensity measurement. The periphery example got when a unique (or focalized) shaft experiences an example of birefringent gem between two polarizers contains data which is intrinsic of the crystalline example under examination.

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Conical extinction curves: a new universal stage technique

Mineralogical Magazine and Journal of the Mineralogical Society ◽

10.1180/minmag.1964.033.265.03 ◽

1964 ◽

Vol 33 (265) ◽

pp. 853-867 ◽

Cited By ~ 4

Author(s):

N. Joel ◽

F. E. Tocher

Keyword(s):

Uniaxial Crystal ◽

Optic Axis ◽

Circular Cone ◽

Biaxial Crystal ◽

Universal Stage

SummaryNew generalized extinction curves, derived from wave-normals located on a circular cone, are presented. They may be used with the universal stage for the accurate location of up to all three of the indicatrix axes, α, β, γ, of any biaxial crystal, or the optic axis of any uniaxial crystal.

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The measurement of large optic axial angles with the universal stage

Mineralogical Magazine and Journal of the Mineralogical Society ◽

10.1180/minmag.1966.035.273.12 ◽

1966 ◽

Vol 35 (273) ◽

pp. 763-769

Author(s):

M. Munro

Keyword(s):

Refractive Index ◽

Rapid Method ◽

High Refractive Index ◽

Optic Axis ◽

Relative Speed ◽

Accuracy And Precision ◽

Direct Location ◽

Speed Accuracy ◽

Universal Stage ◽

Low Refractive Index

SummaryA comparison has been made of the relative speed, accuracy, and precision of several methods of measuring large optic axial angles with the universal stage. It is concluded that a method based on the direct location of a single optic axis and the application of the Biot-Fresnel law will frequently be the most satisfactory when only the standard, low refractive index centre plate for the stage is available. If a centre plate of high refractive index is employed, however, good results can normally be obtained by using the more rapid method based on the direct location of both optic axes.

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Directional Dispersion and Assignment of Optical Phonons in LiNbO3

Zeitschrift für Naturforschung A ◽

10.1515/zna-1972-8-904 ◽

1972 ◽

Vol 27 (8-9) ◽

pp. 1187-1192 ◽

Cited By ~ 25

Author(s):

R. Claus ◽

J. Brandmüller ◽

G. Borstel ◽

E. Wiesendanger ◽

L. Steffan

Keyword(s):

Short Wavelength ◽

Uniaxial Crystal ◽

Optic Axis ◽

Optical Phonons ◽

Dispersion Theory ◽

Phonon Modes ◽

Phonon Wave Vector ◽

Complete Assignment ◽

Firm Basis ◽

Degenerate Type

Abstract From the general polariton dispersion theory it can be shown that in an uniaxial crystal the frequencies of optical phonons * which are identical to those of the short wavelength polaritons depend on the angle Θ between the optic axis and the phonon wave vector. For Θ=0 and Θ=Π/2 the phonons are exactly transversal or longitudinal so that they can be assigned to be of totally symmetric or twofold degenerate type. Careful measurements of the directional dispersion of all phonon modes of LiNbO3 form a firm basis for a new complete assignment. 6 of the total number of 13 dispersion branches previously given in the literature had to be reassigned.

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Three-dimensional birefringence imaging with a microscope tilting-stage. I. Uniaxial crystals

Journal of Applied Crystallography ◽

10.1107/s0021889806007758 ◽

2006 ◽

Vol 39 (3) ◽

pp. 326-337 ◽

Cited By ~ 17

Author(s):

L. A. Pajdzik ◽

A. M. Glazer

Keyword(s):

Refractive Index ◽

Polycrystalline Material ◽

Three Dimensional ◽

Preferred Orientation ◽

Optic Axis ◽

Crystalline Material ◽

Stage I ◽

Specific Group ◽

Optical Indicatrix ◽

Crystalline Materials

The development of a microscope tilting-stage suitable for use with birefringence imaging is described, thus enabling precise three-dimensional birefringence information of uniaxial crystals to be obtained. Equations have been derived for uniaxial crystals in any orientation. The technique enables precise values of the birefringence Δn=ne−no(difference between extraordinary and ordinary refractive index) and orientation of the optic axis to be obtained. The sign of the optical indicatrix may be unambiguously identified. The method is also able to obtain information on preferred orientation in a polycrystalline material. In addition to this, an unknown crystalline material may be identified, or at least classified within a specific group of crystalline materials.

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