Image forming apparatus and image forming method

Abstract

In accordance with an embodiment, an image forming apparatus comprises a main scanning counter, a controller, and an interval determination section. The main scanning counter counts a first count value indicating the number of times a synchronization signal for synchronization between the apparatuses is input to itself, and registers the first count value to an initial value if a main scanning reference signal indicating a progress state of exposure in a main scanning direction is input to itself. The controller generates PreHSYNC generated at the same interval as the main scanning reference signal. The interval determination section determines that an abnormality occurs in the main scanning reference signal if the first count value satisfies a predetermined condition at a timing at which the PreHSYNC is input to itself.

Dependencies are inferred from the claim text.