TSRF Total Spectral Radiant Flux
TLF Total Luminous Flux


The TSRF series of total spectral radiant flux standards are designed for use with integrating spheres with diameters ranging from 100mm to 2m.

Standard calibration range is 380-800nm, but this can be extended to cover 300-2500nm range.

The calibration is performed with respect to National Physical Laboratory (NPL Teddington UK) calibrated lamps held by Bentham. Alternatively, direct NPL calibration can be offered.

For non-spectral measurement lamp photometry the lamps can be supplied with total luminous flux calibration (lumens).

The TSRF and TLF require a precision constant current DC power supply and we recommend the Bentham 610 Power supply.

Units Model No. Lamp rating Power supply current Typical lumens Spectral range Certificate units Typical sphere diameter
mW/nm TSRF4 20W 1.666A 480 380-800nm (ext.300-2500nm) mW/nm 100mm
lm TLF4 20W 1.666A 480 V/λ lm 100mm
mW/nm TSRF8 50W 4.000A 1350 380-800nm (ext.300-2500nm) mW/nm 200mm
lm TLF8 50W 4.000A 1350 V/λ lm 200mm
mW/nm TSRF20 100W 8.500A 2800 380-800nm (ext.300-2500nm) mW/nm 500mm
lm TLF20 100W 8.500A 2800 V/λ lm 500mm
mW/nm TSRF1000 100W 8.500A 2800 380-800nm (ext.300-2500nm) mW/nm 1000mm
lm TLF1000 100W 8.500A 2800 V/λ lm 1000mm
mW/nm TSRF1800 250W 10.400A 9000 380-800nm (ext.300-2500nm) mW/nm 2000mm
lm TLF1800 250W 10.400A 9000 V/λ lm 2000mm