Plate beamsplitters are commonly used with its convenience of utilizing standard optomechanical mounts for most applications. Newport offers a wide range of plate beamsplitters to cover the entire spectrum from UV (250 ~450 nm) to IR (2 µm - 14 µm) regions, in round or square shapes with multiple sizes to choose from. Different types of substrate are offered for different application. UV Grade Fused Silica is the best choice to use in the UV region due to its high transmissivity for UV light and low absorption. The UV beamsplitter are available in 50/50 or 30/70 reflectance/transmittance ratio. Two substrates are available for the IR beamsplitters. CaF2 has a transmission above 90% between 0.25 µm and 7 µm, making it a good choice for deep UV to infrared applications. In addition, with its low absorption and high damage threshold, CaF2 is commonly used for excimer laser applications. ZnSe is the best choice for IR lens with its broad wavelength range. Due to its low absorptions and low thermal expansion properties, ZnSe can also be used with the output of the CO2 laser. Newport Laser Line Non-Polarizing Beamsplitters are insensitive to the polarization of an incoming beam, making them exceptionally useful for higher power applications where cemented cube beamsplitters fail.
Unlike broadband dielectric beamsplitters, which are extremely polarization sensitive, Newport's Laser-Line Non-Polarizing beamsplitters provide a true 50/50 split regardless of the incoming polarization. The polarization components are matched to within 5%. Near zero absorption in these dielectric beamsplitters results in true 50/50 split of the beam and high damage threshold. They are especially useful for higher power applications where cemented cube beamsplitters may fail. These beamsplitters are manufactured using high-precision BK 7 substrates to minimize wavefront distortion. A slight wedge in the substrate helps eliminate back reflections to the laser. The front surface is coated with a multilayer all-dielectric non-polarizing beamsplitter coating optimized for a specific laser line. The back surface is coated with a multilayer dielectric antireflection coating to minimize surface reflection losses and eliminate ghost images. Non-polarizing beamsplitters are available for eleven common laser wavelengths. They are offered in a 25.4 mm diameter size to conveniently mount in Newport ULTIMA® Series, PERFORMA Series, and GM Series mounts.