Zero-Order Quarter Wave Plate, Quartz, 25.4 mm Diameter, 850 nm

The 10RP04-30 Zero-Order Quartz Wave Plate is a temperature insensitive phase retarder for moderate bandwidth applications. This zero-order wave plate is constructed of two quartz plates, air-spaced to allow for use with high-power lasers. The assembly is held in a 1 inch (25.4 mm) diameter black anodized aluminum housing to protect the optic and permit convenient handling and mounting. The wave plate is antireflection coated to maximize transmission at the 850 nm wavelength, and has a λ/4 retardation. Retardation in zero-order wave plates is insensitive to temperature since thermal changes between the multiple-order wave plates tend to cancel. A typical zero-order wave plate has a temperature coefficient of 0.0001 λ/°C compared to 0.0015 λ/°C for a multiple-order wave plate, providing less change in retardation over an extended temperature range. Zero-order wave plates offer several distinct advantages over multiple order wave plates. The primary benefit is a moderate insensitivity to wavelength change, making them ideal for laser diode or tunable laser applications. For example, a zero-order wave plate designed for 780 nm will provide useful retardance from 765–795 nm. By combining two wave plates whose retardations differ by exactly λ/4 or λ/2, a true λ/4 or λ/2 wave plate results. The fast axis of one plate is aligned with the slow axis of the other, so that the net retardation is the difference of the two retardations.