Editing Photoelasticity (section)

==Plane polariscope setup==
The setup consists of two linear [[polarizer]]s and a light source. The light source can either emit monochromatic light or white light depending upon the experiment. First the light  is passed through the first polarizer which converts the light into plane polarized light. The apparatus is set up in such a way that this plane polarized light then passes through the stressed specimen. This light then follows, at each point of the specimen, the direction of principal stress at that point. The light is then made to pass through the analyzer and we finally get the fringe pattern.{{cn|date=September 2022}}

The fringe pattern in a plane polariscope setup consists of both the isochromatics and the isoclinics. The isoclinics change with the orientation of the polariscope while there is no change in the isochromatics.{{cn|date=September 2022}}

[[File:Transmission Circular Polariscope.svg|thumb|Transmission Circular Polariscope<br>The same device functions as a plane polariscope when quarter wave plates are taken aside or rotated so their axes parallel to polarization axes]]