Simulation of errors in automated photoelasticity

In automated photoelasticity, there are some advantages in using white light; however, the theory underlying many such systems, namely phase stepping, is based on monochromatic light. The effect of using white light has been investigated both by experiment and by a simulation of a polariscope. The simulation has been validated and used to explore the use of bandwidth filters to control the errors caused by using white light. These errors were found to be dependent on the form of the spectrum of the light and to be large for high fringe orders.