References in periodicals archive ?
This source can be either an integrating sphere with known spectral radiance at its exit port or a diffuse reflector, of known reflectance factor, illuminated by a source of known spectral irradiance.
Distances of up to 600 feet between emitter and receiver can be handled with through-beam systems; spaces as small as millimeters can be measured with fiber-optic proximity or diffuse reflectors.
Furukawa's MCPET is able to achieve the highest-class reflectance ratio of all diffuse reflectors by featuring extra-fine bubble diameters of 10 microns or less.

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