A METHOD AND AN APPARATUS FOR DETECTING CONCENTRATIONS OF FIRST AND SECOND TONER PARTICLES IN A DISPERSION

摘要

Concentration detection of first and second toner particles in a dispersion, including illuminating the dispersion with linearly polarized light having a given polarization direction, detecting an amount of light passed through the dispersion and through an analyzer set at a predetermined angle to the given polarization direction and determining at least the concentration of one of the toner particles utilizing the detected amount of light. Additionally the concentration detection may include further illuminating the dispersion with unpolarized light, and further detecting a second amount of light passed through the dispersion illuminated with the unpolarized light, where both of the toner particle concentrations are determined from the detected and the second detected amounts of light.