Optometrics USA Inc. has introduced a 50/50 reflecting/transmitting beamsplitter that maintains a constant reflection-to-transmission ratio over the UV to IR region. It consists of a UV-grade fused-silica substrate with an aluminum coating that is applied in certain-size apertures, giving the beamsplitter a "polka dot" appearance. The beam is split evenly by reflection from the aluminized coating and transmitted through the nonaluminized portion. The beamsplitter's net loss and 50% splitting ratio are virtually flat over the entire 250- to 2500-nm wavelength range. It is suitable for any broadband extended source such as tungsten or xenon, and for ratioing and sampling in monochromators, spectrophotometers and radiometers.