The 70677 Uniform Source Integrating Sphere can be placed at the output of a light source and you have an almost perfectly uniform Lambertian, broadband source. Typical radiance uniformity is within 1-2% of the average over the 2 inch (51 mm) diameter exit port as long as the FOV of the imaging system stays on the baffle within the sphere. Irradiance uniformity at the port is also better than 1-2%. For a tunable, uniform light source, couple the sphere to the input of a monochromator or motorized filter wheel. You'll need the 77829 Coupling Ring to attach one of these to an Oriel Monochromator. To make a uniform calibration source with several orders of luminance range, attach a filter wheel with neutral density filters to the sphere's input. The input port of the sphere has a 1.5 Inch Series male flange so it can be mated to an Oriel Light Source. The output port is a 2 inch (51 mm) diameter port frame for simple mounting of samples. This 8 inch diameter sphere has a Barium Sulfate coating for a 350 to 1300 nm range, and (3) 2 inch ports.