Polarised or not Polarised? This is the Problem

Selecting the Infrared Sensors I just Did not understand the difference between a Polarized Light Sensor and not Polarized type...
Can anybody help me ?

Polarized retroreflective photo-cells are typically used where the object being sensed has a very shiny, reflective surface. The polarizing filters in these sensors will ignore relflections from a shiny surface and will only "see" the depolarized reflections from its reflector target.

The polarizing filters in these sensors will ignore relflections from a shiny surface and will only "see" the depolarized reflections from its reflector target.

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Most of the time....