Photoelastic effect

The photoelastic effect is the effect in which a change of the refractive index is caused by stress. The changes 

The Miller delta formulation is soEi(ayi) = SijkPj(( i)Pk(fi 2), where the Miller coefficient, 

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Through the photoelastic effect, stress will modify the refractive index of silicon according to the relations... 

One also observes crosses in polarized light which are deformed when the stage is rotated. This has been attributed to photoelastic effects of stress applied to a point. 

Thus, by using the photoelasticity effect, we managed to ascertain for the first time that the hypercrossHnked polystyrene network can experience inner stresses of shrinkage on drying, stresses of extension on sweUing in good solvents, and also can acquire a fuUy relaxed state, totally free from any stresses, when wetted with methanol. Dusek and Prins [163] have postulated a pecuHar reference state when polymeric chains do not exert any forces on network junction points (see also Chapter 1, Section 2.2), but this state of... 

An independent method of determining stress, especially useful for materials under flow, is from the optical birefringence. Of course, it is limited to transparent materials, which precludes application to filled polymers. Because of the need for transparency, stress birefringence has been used more often for plastics than rubber. Residual anisotropy due to unrelaxed orientation can also be assessed using birefringence this is commonly known as the photoelastic effect. Generally the birefringence is directly proportional to the tme stress... 

The study of optico-mechanical properties of one of ladder polyphenyIsesquioxanes in bulk has revealed the complex nature of the photoelasticity effect in the films of this polymer. Ladder polymers are characterized by high equilibrium rigidity of double stranded chains. ... 

Muller H (1935) Theory of the photoelastic effect of cubic crystals. Phys Rev 47 947-957... 

Optical phenomena depending on crystal structure Electro-optic effect Magneto-optic effect Photoelastic effect Optical switch Display Modulator, optical deflector Optical isolator Optical circuit device (active device) Optical fiber sensor... 

Introduction Photoelastic Effect Acousto-Optic Effect... 

A material s optical index of refraction is coupled to its mechanical strain via the photoelastic effect, traditionally expressed by a fourth-rank tensor,... 

An acoustic wave can produce a strain causing a change in the index of refraction via the photoelastic effect (Dixon, 1967). It has been shown (Pinnow, 1970) that the change in the index of refraction is related to the acoustic power Pa by the expression... 

Photoelastic effect Mechanical strain in a solid causes a change in the index of refraction that can affect the phase of a light wave traveling in the strain medium. This is called the photoelastic effect. 

In the case of lateral compression, the propagated fundamental mode perfectly degenerates into x- and y-polarized modes with different propagation constants. According to the photoelastic effect and the stress strain relationship, the effective index changes of the two polarized modes ean be expressed as ... 

Variation of refractive indices with mechanical strain (photoelastic effect)... 

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