Our Polarizing filters for industrial cameras are constructed with dichroic sheets of laminated polymers, that are fixed between protective glasses. The direction of the linear polarization can be adjusted by turning the top ring of the filter. This ring can be fixed by a screw, to make sure that the linear polarization filter direction stays fixed.
When to use a Polarizing Filter?
A linear polarizing filter is used to remove reflections from light sources on shiny objects. When a linear polarized light source hit a surface it gets again polarized in all directions, except the direct reflection. The direct reflection will stay in its original polarized direction. Mounting on the lens of the camera a linear polarized filter, that is polarized in a different direction than the direct reflection of the light source, the direct reflection will be blocked. As a result, the image will have no reflection of the light source.