Instrument Systems developed a complete family of integrating spheres in the ISP series with the objective of marketing a broad spectrum of sizes and functionalities. Integrating spheres with diameters from 75 mm to 2 m therefore allow the characterization of a wide range of different light sources with a very high level of precision.

All integrating spheres are coated with barium sulfate (BaSO4) with a reflectance of approximately 97% in the photometric spectral range. The coating exhibits inimal ageing effects and has a particularly low fluorescence level. It covers a wide spectral range from 240 to 2600 nm.

The complete model range can be used with all spectroradiometers from Instrument Systems. A fiber bundle is generally used to connect the sphere to a spectroradiometer which is optimized for the relevant spectral range.

Integrating spheres from Instrument Systems are in conformity with the guidelines CIE 127:2007,
CIE S 025 and IES LM-79-08 in respect of concept, construction and functionality. The complete ISP series has a measuring port at the side to determine luminous flux in 2π configuration. In accordance with the recommendations referred to, this measuring port is always less than 1/3 of the diameter of the sphere limiting the maximum dimension of the luminaire being measured to an optimal amount.