The polarization of the light is a physical property that characterizes the way in which light waves oscillate. This property is not visible by the human eye, but some materials scatter light differently depending on the polarization of the light they receive : they are called optical filters because they filter the light depending on its polarization. See the Polarization section for more details on polarization.

Predict Matter supports different types of optical filters :

• Linear polarizer : transmits light if it is polarized linearly at the given angle.

• Circular polarizer (left or right) : transmits light if it is polarized circularly in the given direction.

• Retarder : induces a phase shift to the light polarization at the given angle. Half and quarter wave plates are retarders that induce a half wave or a quarter wave phase shift.

• Diattenuator : modifies the light intensity differently depending on the polarization. The intensity will be multiplied by a cosinus or a sinus of gamma whether it is polarized at the given angle or orthogonal to the given angle. With a gamma of 45°, the diattenuator is equivalent to a neutral density filter.

• Rotator : induces a rotation of a given angle to the polarization state.

• Neutral density filter : modifies the light intensity without regard to its polarization.

• Depolarizer : modifies the light intensity and depolarize the light completely.

• Custom optical filters : custom filter defined by its transmission Mueller matrix.