3d polarized glasses are not all the same. Despite the inherent differences between linear polarized and circular polarized, I've noticed a difference in the amount of polarized light filtered when switching between my LG TV glasses and my Acer glasses. In playing a 3d game I can put my character up against a background with a much different color and contrast and I can notice a slight ghosting at times. If I switch to my LG glasses this ghosting comes through even more. I think there is a bit of light that isn't getting filtered out and being noticed in these situations. Since my higher quality Acer 3d polarized glasses even has light get through, I would still be interested in finding a better pair. When and if this market ever gets better I imagine they will rate these glasses by how efficient they are at filtering the polarized light.
Added later: Turns out I'm wrong, so scrap what I wrote above. I put my LG TV on the Smart app called Yabazam which shows 3d trailers and my LG glasses showed least amount of ghosting and the Acer glasses a lot more. They must be different types of polarization. Funny that they both work on each , it's just in different areas the glasses not designed for each monitor/TV showed ghosting or more ghosting in particular areas.
Added even later: (maybe I need to know what I'm talking about before I post :-D) I can tilt my head with the Acer glasses on when viewing my TV and the ghosting will disappear. Some articles I read state this means they are linear polarized and I wonder if each of the glasses just have the polarization at a different angle. But I'm not sure, maybe circular polarized will show some ghosting with head tilts on big differences in contrast??