Polariscope Strain Viewer for Glass and Plastics

Presto's Glass & Plastic Polariscope - Strain Viewer is the best and highly effective testing device which is used to measure the residual stresses and strains that are introduced during the manufacturing process of the products that severely affects the strength of the product. These effects can be harmful as it may contribute to the product’s failure in service or it can be beneficial, as for example in the inducement of compressive stresses in the surface layers of toughened glass to increase its strength in service.

One of the most powerful methods, where the product is made of transparent glass or plastics, is based upon the photoelastic technique which involves the passing of polarized light through the product and interpreting, qualitatively or quantitatively, the resulting optical interference pattern. In the case of glass products, it is usually the residual stresses which are measured whilst in the case of plastics molding, casting or extrusions it is the strains which generally are of importance. The testing instrument is manufactured by considering relevant parameters and various standards that are introduced by standardized and reputed authorities.

Standard

Material

Industry

Test