Polarization-entangled photon pairs are generated using crossed Beta Barium Borate crystals analogous to Dehlinger and Mitchell’s method. The polarization state of the entangled pairs is projected onto the basis of two polarizers introduced in the signal and idler arms. The cosine-squared dependance of the probability amplitude of the entangled state on the relative polarizer angle is theoretically explained and verified. The relative phase between the horizontal and vertical polarizations is minimized by adjusting the quartz plate. A test of the Clauser, Horne, Shimony and Holt version of the Bell Inequality finds S = 2.198, in clear violation of hidden variable theories.