Polariscope Strain Viewer computerised is utilized for conducting Quality and Transparency test. It is used to identify and evaluate residual strain in PET preforms, bottles and similar products.

It works on the standard principle of using polarized light to identify strain in preforms. The Polariscope incorporates a polarizing filter to convert white light into a straight lined polarized beam which is directed through the sample. Actual level of stress in the specimen can easily be determined by comparing colours exhibited during the test with those produced by calibrated defect chart.