Patent ID: 7505699

Claim:
An image forming apparatus comprising: an image bearing member on which an electrostatic latent image is capable of being formed; a developer accommodating container for accommodating a developer for developing the electrostatic latent image; a detecting device for detecting a remaining amount of the developer in said developer accommodating container, wherein said detecting device detects the remaining amount during a period in which no image forming operation is performed; and a developer stirring member for stirring the developer in said developer accommodating container, said developer stirring member being rotatable at a speed which is lower during detection of the remaining amount than when an image forming operation is performed, wherein said detecting device detects first, second and third developer remaining amounts in first, second and third remaining amount detecting periods, respectively, in the order named, and wherein an interval between the second detection period and the third detection period is changed on the basis of the first and second remaining amounts, wherein said detecting device detects the remaining amount of developer by detecting light passing through a transmission port provided in said developer accommodating container.