| 摘要 |
PURPOSE:To accurately measure charge quantity possessed by toner particles, by a method wherein charged toner particles fall between parallel opposed electrode plates and laser beams are crossed at a measuring position while scattered light is photoelectrically converted to measure the charge quantity of toner as Doppler frequency. CONSTITUTION:Voltage is applied between parallel electrode plates 1a, 1b from a DC power source 3 and charged toner particles freely fall. At this time, charged toner particles 4 are attracted to the electrode plate having polarity inverse to charged polarity and the locus corresponding to the charge quantity is obtained. The laser beam 6 from a laser beam source 5 is divided into two beams 6a, 6b having almost equal intensity by a beam splitter 7 and two laser beams are crossed at a measuring position P through a first lens 8. The scattered beam from the measuring position is guided to a detector 12 to obtain an electric signal. The charge quantity per a particle size is directly proportional to Doppler frequency. |
