The LBTEK Quartz True Zero-Order Quarter-Wave Plate is made from a single piece of quartz crystal, with a thickness on the micrometer scale and a low mechanical strength, but it allows for a larger incident angle. When a beam of linearly polarized light is incident perpendicularly on a waveplate made of uniaxial crystal, it splits into o-light and e-light that propagate along the original direction but vibrate perpendicularly to each other, with corresponding refractive indices no and ne. Due to the different velocities of the two lights in the crystal, the phase retardation produced after passing through a waveplate of thickness d is δ = (2π/λ)|no - ne|d. Here, |no - ne|d is the optical path difference, and the optical path difference produced by a quarter-waveplate is (2m + 1)λ/4, with a phase retardation of δ = (2m + 1)π/2, where m is a non-negative integer. For a true zero-order quarter-wave plate, m is 0. The LBTEK Quartz True Zero-Order Quarter-Wave Plate is commonly used to convert linearly polarized light into circularly polarized light. Compared to quartz multi-order waveplates, the quartz true zero-order waveplate is insensitive to temperature and incident angle, making it suitable for high-power applications. Additionally, the quartz true zero-order waveplates sold by LBTEK come with a mechanical housing that is non-removable for ease of use. Besides the standard quartz true zero-order quarter-wave plates, LBTEK also offers various customization services, including special dimensions, design wavelengths, and phase retardation specifications. For customization needs, please contact LBTEK Technical Support.