The present invention is directed to an apparatus and method for measuring the haze value of transmissive samples. The apparatus comprises a first light source selectively configurable to emit a first light beam, a second light source selectively configurable to emit a second light beam, an integrating sphere having an outer surface and an inner surface, the inner surface configured to reflect light incident upon the inner surface, the inner surface further enclosing an interior volume. The integrating sphere is further equipped with an exit port configured to emit light from the interior volume of the integrating sphere. The exit port is positioned such that light from the first light source exits the integrating sphere without obstruction, and light from the second light source is diffused on the interior surface of the integrating sphere prior to exiting the exit port. A light detector is also included and is configured to generate a light-intensity signal when light exiting the integrating sphere has passed through a sample and is incident on the light detector. The apparatus further includes a processor configured to receive the light-intensity signal and generate an output signal to a user indicating the haze value. The present invention is also directed to a method of calculating the haze value of a sample using a stored calibration value, a diffuse transmission value (sample-absent diffuse light-intensity value), a direct transmission value (sample-absent direct light-intensity value), a measured diffuse transmission value (sample-present diffuse light-intensity value) and a measured direct transmission value (sample-present direct light-intensity value).