Broadband Polarizing Cube Beamsplitters

These beamsplitters consist of a pair of precision right-angle prisms carefully cemented together to minimize wavefront distortion. The hypotenuse of one of the prisms is coated with a metal-dielectric hybrid beamsplitter coating optimized over a broad wavelength range. The four faces are antireflection coated with a broadband multilayer dielectric coating to minimize surface reflection losses over the wavelength range. Due to the metallic nature of the hybrid coating, these beamsplitters are not intended for use with higher power lasers.

Cube beamsplitters are formed by cementing two right angle prisms together. One of the two prisms has the partially reflective metal-dielectric coating applied to its hypotenuse. In Newport's cube beamsplitters the coated prism is marked with a visible dot. Incident light should enter the prism with the coated hypotenuse in order to minimize power passing through the optical cement. Alternatively, a beam entering via the uncoated prism results in more than triple the fluence in the cement (the transmitted component, plus a double pass by the reflected component). With higher power beams this can result in degradation of the cement.

Four broadband multilayer coatings are offered covering the 420–680 nm, 620–1000 nm, 900–1300 nm, and 1200-1600 nm wavelength ranges