Device and method for electrophotographic image generation

• Main Author: KOSHIO; TAKESHI
• Format: Patent
• Language: English
• Published: 25.04.2000
• Edition: 7
• Subjects: CINEMATOGRAPHY; ELECTROGRAPHY; ELECTROPHOTOGRAPHY; HOLOGRAPHY; MAGNETOGRAPHY; PHOTOGRAPHY; PHYSICS

An electrophotographic image generation device such as an electrophotographic printer comprises an image bearing belt, a development section, a toner image transfer section, a toner concentration sensor, and an electrical charge control section. A latent image due to variations in electric potential is formed on the image bearing belt by irradiation of photo image light. The development section applies a liquid developing agent on the surface of the image bearing belt and thereby changes the latent image into a visible toner image. The toner image transfer section transfers the toner image on the surface of the image bearing belt to the surface of a sheet and thereby executes printing to the sheet. The toner concentration sensor detects the concentration of toner particles in the liquid developing agent. The electrical charge control section controls the amount of electrical charges on the toner particles in the liquid developing agent in the development section, according to the toner concentration detected by the toner concentration sensor. The electrical charge control is executed very quickly, for example, by controlling a development bias voltage applied to a development roller. Therefore, the density of printed picture images can be maintained constant even if the toner concentration in the liquid developing agent varied.