Polka Dot Beamsplitters
Optometrics’ polka-dot beamsplitters provide constant reflection to transmission ratio over the entire 250 to 2000nm range using a fused silica substrate or 400 to 2000nm wavelength range on SCHOTT B270® ultra-white glass substrate. The “polka dot” appearance of these beam splitters comes from the combination of a photolithography process and the vacuum deposition of aluminum. The result is a precise pattern of small aluminum “dots” on the glass substrate. The beam is split by reflection from the aluminized dots and transmission through the non-aluminized portion of the substrate. The design angle for these polka-dot beamsplitters is 45 degrees. The reflectance will be slightly less at zero degrees but with an insignificant impact on split ratio. These patterned area metallic beamsplitters exhibit minimal angle and wavelength sensitivity giving them a big advantage over other beamsplitters.
