LBTEK's Quartz True Zero-Order Quarter-Wave Plates are fabricated from a single crystalline quartz plate with micron-scale thickness. While this design has limited mechanical strength, it allows for a significantly larger angle of incidence (AOI). When a linearly polarized beam is normally incident on a uniaxial crystal wave plate, its electric field resolves into two orthogonal components—the ordinary (o) and extraordinary (e) waves. These waves propagate along the original optical axis but experience different refractive indices, no and ne, respectively. Due to the distinct velocities of these two waves within the crystal, a phase retardance δ = (2π/λ)|no - ne|d is accumulated after traversing a wave plate of thickness d. Here, |no - ne|d represents the optical path difference (OPD). For a quarter-wave plate, the OPD is defined as (2m + 1)λ/4, resulting in a phase retardance of δ = (2m + 1)π/2, where m is a non-negative integer. For a true zero-order quarter-wave plate, m is 0. LBTEK's Quartz True Zero-Order Quarter-Wave Plates are commonly used to convert linearly polarized light into circularly polarized light. Compared to quartz multi-order wave plates, these true zero-order devices are less sensitive to temperature fluctuations and AOI, making them ideal for high-power applications. Additionally, LBTEK offers these wave plates in non-removable mechanical housings for ease of use. In addition to our standard quartz true zero-order quarter-wave plates, LBTEK offers comprehensive custom capabilities, including specialized dimensions, operating wavelengths, and tailored retardance values. For specific inquiries, please contact LBTEK Technical Support.