Patent ID: 8086126

Claim:
An image forming apparatus comprising: a developer container containing a developer for developing an electrostatic latent image that has been formed on an image carrier; a developer carrier for developing the electrostatic latent image by supplying the image carrier with the developer within said developer container; an electrode member opposing said developer carrier via a space accommodating the developer inside the developer container; a high-voltage power supply including: an AC voltage generating circuit for generating an AC voltage by switching a DC voltage; a transformer; a rectifying circuit for rectifying the AC voltage received from said AC voltage generating circuit via said transformer and generating a DC voltage; and an AC voltage applying unit for applying the AC voltage, which is output from said transformer, to said electrode member; and a developer remaining-amount detection unit for detecting an amount of developer remaining inside said developer container based on electrostatic capacitance between said developer carrier and said electrode member.