Polarizing Optics

For a single H-V type depolarizer, it cannot depolarize all polarized light, particularly linearly polarized light in horizontal and vertical orientations, thus limiting its application scope. A single H-V depolarizer can be regarded as a Wollaston prism with an extremely small structural angle. As shown in Figure 1, light is split into light beams o and e in the front half, propagating orthogonally and in the same direction; in the rear half, it is further divided into two beams—oe and eo—which are linearly polarized with opposite refraction directions. The intensities of these two beams vary with the azimuth angle according to sine or cosine laws, typically differing from each other, resulting in significant polarization correlation. Therefore, when using an H-V depolarizer for monochromatic light depolarization, an azimuth angle of 45° is required.   Figure 1   Based on the principle of H-V type depolarizers, two H-V type depolarizers are combined through a 45-degree rotation to form a dual Babynett-type depolarizer, as shown in Figure 2. This design enables the second H-V type depolarizer to effectively depolarize the horizontal or vertical linear polarization components in the first H-V type depolarizer, thereby overcoming the functional limitations of a single H-V type depolarizer.   Figure 2: Structural diagram of the dual Babynine-type depolarizer