When I input horizontally polarized light (in the x-direction) into a 1/4-wave plate oriented at a 135-degree angle relative to the x-axis, it should generate clockwise circularly polarized light. Subsequently, after reflecting this light using a mirror, it should become counterclockwise circularly polarized. When this reflected light encounters a 1/4-wave plate, theoretically, it should result in vertically polarized light (in the y-direction). However, what I observed in the polarization pupil map is horizontally polarized light in the x-direction. Have I overlooked something, or have I misunderstood a certain definition?