High-pass optical filter

Long and Short Pass Edge Filters * High transmission and high rejection for complete isolation * Available at every 50nm throughout the visible and near-IR * Cut-on and cut-off wavelengths guaranteed to within 10nm * May be tilt tuned to shorter cut-on/cut-off wavelengths These are interference filters which provide a sharp cut-off either above or below a particular wavelength. They are useful for isolating regions of the spectrum. These filters are specified by their center (50% transmission) wavelength. The transmission of the long pass filters is 85% from a wavelength that is 3% greater than the specified wavelength to 2000nm. The transmission of the short pass filters is 85% from a wavelength that is 3% less than the specified wavelength to 425nm (except for the 400nm filter). The width of the transition from cut-on to cut-off is typically 6% or less of the center (specified) wavelength.