Patent ID: 6603934
Filing Date: 2003-08-05
Classification: G03G

Abstract:
An electrophotographic developing apparatus which develops a latent image on a photosensitive body by use of a toner liquid in which toner is dispersed in a non-polarity solvent and which forms a toner image on the photosensitive body, said electrophotographic developing apparatus comprising:a photosensitive body which holds an electrostatic image; a charging unit which provides the photosensitive body with a predetermined potential; an exposure unit which forms an electrostatic image on the photosensitive body; a developing unit which includes a developing roller opposing the photosensitive body with a predetermined gap maintained, and which supplies a toner liquid to the electrostatic image formed on the photosensitive body such that toner is selectively attached to the electrostatic image, thereby forming a toner image; a developing bias source which applies a predetermined bias voltage to the developing unit; a toner layer thickness-detecting mechanism which detects the thickness of toner constituting the toner image, said toner layer thickness-detecting mechanism including an emission system which emits polarized light toward the toner image formed by the developing unit, and a reception system which receives the polarized light reflected by the toner image and produces an electric signal; an image formation condition-controlling device which controls at least one of an output from the charging unit, an output from the exposure unit and the bias voltage applied by the developing bias source, on the basis of the thickness of the toner layer detected by the toner layer thickness-detecting mechanism; and a toner liquid replenishment mechanism which supplies the developing unit with a toner liquid whose toner density is a predetermined value, said toner density being a ratio representing how much the toner is dispersed in the non-polarity solvent.