A Glan-Taylor polarizer produces linearly polarized light. It’s made of a pair of right angle prisms which are separated on their hypotenuses with an air gap. The optical axes of the optical crystals are aligned parallel to the plane of reflection. S-polarized light encounters a total internal reflection at the air gap; therefore only p-polarized light is transmitted. While the transmitted beam is 100% p-polarized, the reflected beam is not totally s-polarized.