In this experiment a polarizing filter, set to o deg., is placed before the left slit of a double slit and a polarizing filter, set at 45 deg., is placed before the right slit.
UPDATE: Having possibly demonstrated near field interference, first using mirrors and second using baffles, it seems that it should also be possible to demonstrate it using polarity.
Separately Polarized Double Slit Experiment In this experiment a polarizing filter, set to o deg., is placed before the left slit of a double slit and a polarizing filter, set at 45 deg., is placed before the right slit. This produces a scattered pattern of individual double slit interference spacing. Then a polarizing filter is placed in front of the target screen, set to 135 deg. or at 45 deg., perpendicular to one or the other slit filters. Half of the double slit patterns remain. Sense only most of the light from one of the slits can reach the target screen the double slit interference pattern between the two paths must have been formed prior to reaching the target screen. The disappearance of light from some of the other previously separated, or individual, pattern areas makes the path through which slit determinable for those areas. Because the filter in front of the target screen will diffuse the double slit patterns in a short distance, it is necessary to place the filter close to the screen, less than 2 cm. It is also necessary to have a large distance between the double slits and the target filter, 10m to 15m, to create large patterns for the same reason. This is a tertiary experiment sense the filters are not a 100% effective. However, they are effective enough to demonstrate the principle and to suggest the value of eventual more controlled experiments. Below is included a diagram of the experiment and a photograph of the scattered double slit patterns without the target polarizing filter.
