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Welcome to the PSA section of the Stress Photonics home page. This section is a complete guide to the new Grey-field polariscope by Stress Photonics. Read on to see how the new GFP 1000 is making photoelasticity a truly "Paint and Shoot" technique.

GFP 1000 is a strain measurement system based on photoelasticity. Although the measurement instrument is very different than those of the past, the technique is well founded in the fundamentals of photoelasticity that have been used for decades. After a thin plastic coating is applied to the surface of the part, an instrument called a polariscope measures the strain induced birefringence to create a full-field strain map.

Key Points about Photoelasticity
  • Full-field
  • Thin plastic coating
  • In-plane shear strains
  • Directions of principal strains
  • Simple static loads including assembly stresses
  • Should view normal to surface
  • Can measure residual stress in glass and plastic

Key Features of the GFP 1000
  • Automated full-field strain measurement
  • Compatible with all coatings
  • Thickness measurement via tinted coatings
  • 20 microstrain resolution typical
  • Sub-fringe or multi-fringe
  • Simple static loading
  • Traceable system calibration
  • No fringes to analyze
  • Automatic measurement of coating thickness
  • Fully computerized digital system
  • Thin easier to apply coatings