Optical Specifications	Value
Transmission Band 1	Tavg > 65% 270 – 290 nm
Blocking Band 1	ODavg > 5 200 – 260 nm
Blocking Band 2	ODavg > 5 310 – 380 nm
Blocking Band 3	ODavg > 4 380 – 700 nm
Center Wavelength 1	280 nm
Guaranteed Minimum Bandwidth 1	20 nm
FWHM Bandwidth 1 (nominal)	22 nm
General Filter Specifications	Value
Angle of Incidence	0 ± 5 degrees
Cone Half-angle	7 degrees
Optical Damage Rating	Testing has proven to show no signs of degradation when exposed to at least 6.0 W of power from an unfiltered xenon arc lamp over a 25 mm diameter (corresponding to 1.2 W/cm2) for over 500 hours.
Physical Filter Specifications	Value
Transverse Dimensions (diameter)	25 mm
Transverse Tolerance	+ 0.0 / – 0.1 mm
Filter Thickness (mounted)	5.0 mm
Filter Thickness Tolerance (mounted)	± 0.1 mm
Clear Aperture	≥ 21 mm
Scratch-Dig	60-40
Filter Thickness (unmounted)	2.0 mm
Filter Thickness Tolerance (unmounted)	± 0.1 mm
Orientation	Arrow on ring indicates preferred direction of propagation of light

Topic	Description
Cleaning Optical Filters	Instructions for cleaning hard coated optical filters
Filter Reliability	Compares the performance and reliability of hard coated filters to traditional soft-coated filters and provides information about the testing standards for Semrock filters
Working with Optical Density	Tables to describe the relationship between OD and transmission with tips for quickly calculating OD

280/20 nm BrightLine® single-band bandpass filter

Specifications