Charging method and developing device adopting the same

The charging method of a developing agent for use in image forming processes for supplying a developing agent as charged by charging means and transferring the image from the image transfer means onto the recording material, comprising the steps of:

• projecting a light onto said charging means by light-projecting means;
• charging the developing agent by electrons as generated by the photoelectric effect at an electron discharging section provided in said charging means;
• measuring the amount of electrons discharged from the electron discharging section;
• and
• adjusting the amount of light to be received from said light-projecting means by multiplying an initial amount of received light by “t”.

A developing device, comprising:

• light-projecting means for projecting light onto a developing layer thickness regulating/charging means;
• an electron-discharging means for inducing own electrons by receiving the light projected from said light-projecting means and discharging the electrons, said electron-discharging means being provided in the developing agent layer regulating/charging means;
• measuring means for measuring an amount of electrons discharged from said electron discharging section;
• and
• control means for adjusting the amount of light to be received from the light-projecting means by increasing it to “t” times of an initial amount of light received when the amount of light received is measured to be 1/t of the initial amount.

A developing device, comprising:

• transport means for transporting a developing agent held on an electrostatic latent image holding means;
• supply means for supplying the developing agent to said transport means;
• developing agent layer thickness regulating/charging means being projected with an electron discharging section for inducing own electrons by receiving light and discharging the electrons;
• electric bias means for increasing/accelerating the electrons discharged by said electron discharging section;
• and
• control means for controlling an amount of electrons discharged from the electron discharging section to be a predetermined value.