I recently saw two 3D movies using ‘RealD’ technology. The effect was very good. I concomitantly acquired two, presumably identical, pairs of ‘polarized glasses’. The technology is ‘RealD. The document pushes RealD but gives some information on two current alternate technologies. This gives some more detail. These ‘passive’ glasses ‘cost’ $1.50 extra and have no moving or electronic parts. (Some variations requires batteries.) Slide 19 of the first document describes Real D as using circular polarization which I had already deduced. The first chart does not even mention linear polarization.
|FRPFR||o||Light going thru two parallel right lenses in theater direction is not much attenuated, at least not much more than one lens, but it is given a slight orange hue ('o'). A single lens does not color the light.|
|FRTFR||b||The same lenses when turned give a slight blue hue ('b'), yet little attenuation.|
|FyPFz||o||Both lenses do the same, even mixing left and right.|
|FyTFz||b||ditto. (4 cases)|
|ByPBz||o||I think thermodynamics requires this considering FyPFz.|
|ByTBz||b||ditto (no one way mirrors)|
|xyPxz||o||In general (8 cases)|
|FRPBR||c||Light travels thru second lens backwards. The hue is gone ('c') “clear”. Very little additional attenuation.|
|FxPBy||c||four cases here.|
|FxTBy||0||Black! only a percent or so of blue light gets thru. Notice so far no distinction between left and right lenses!|
|BxPFx||c||clear again if we match lenses.|
|BxPFy||p||dark purple if x≠y. Perhaps 20% of light gets thru.|
|BxTFx||0||black again as for FxTBy.|
|BxTFy||c||Very clear if x≠y! no coloration.|
I am confused!
Further experiments would involve a mirror which I think I understand!