A quarter- or half-wave retarder made from two plates of quartz with their fast axes crossed, the difference in thickness between the two plates determines the retardance. Zero-order retarders provide accurate retardance over a broad range of wavelengths and are more durable than single-element retarders.

Advantages:

• Double Retardation Plates
• Broad Spectral Bandwidth
• Wide Temperature Bandwidth 
•  AR Coated

Specification:

                                                            *  Other sizes and coatings are available upon requirements.