optical discs have birefringence, which may also cause polarization of the reflected beam. So, the reflected beam is polarized due to the birefringence and the liquid crystal panel. As a result, the reflected beam is elliptically polarized due to the birefringence rather than being linearly polarized by the liquid crystal panel. In other words, the reflected beam contains vertical as well as parallel components in the polarization angle of the laser beam.
As a result of the polarization due to the birefringence, the amount of light received by the photo detector decreases due to the phase differences. For example, when the phase difference caused by the birefringence is xcfx80 radian, no beam is guided to the photo detector, and the information recorded on the optical disc cannot be read.New York Rangers forward Rick Nash was injured Friday during a game in Switzerland, his agent told TSN.

"Rick was taken out of the game for precautionary measures and will be re-evaluated over the next couple of days," Nash's agent Joe Resnick said, according to the network.

Nash signed with HC Davos of the Swiss National League A earlier this month. TSN reported Nash was injured nine minutes into the game against HC Lugano after being hit into the glass.