A New Pc-Based System For Fully Automated On-Line Stress Measurement Of Heat Strengthened And Tempered Glass

Heat-strengthened and fully tempered glass can be as much as three to seven times as strong as annealed glass, depending upon such factors as actual residual surface compression. The additional strength is due to the residual compressive stress in the surface and edge layers, offsetting tension due to handling, impact and service loads. Since the increased strength is the product's main characteristic, there is an obvious need to implement systematic quality control stress testing programs to ensure conformance to US and EU specifications. This article describes how Strainoptic Technologies have met this challenge.