Patent ID: 8295721

Claim:
An image-forming device comprising: an image bearing member having a surface moving at a surface speed; an image-forming unit configured to form an actual test pattern on an actual position of the surface in accordance with pattern data, and configured to form an image in response to an image-forming instruction; a detecting unit configured to detect the actual position; a processor; memory storing computer readable instructions that, when executed by the processor, cause the image-forming device to: provide the pattern data indicative of a target test pattern to be formed on a target position of the surface in response to a test instruction; calculate a deviation of the actual position from the target position; perform a first determination of whether the surface speed is stable or unstable when the test instruction is received; perform a second determination of whether the surface speed when the image-forming unit receives the image-forming instruction is stable or unstable; and calculate a correction amount based on the deviation, the first determination, and the second determination; and a storing unit configured to store a first correction information including the actual position and the first determination; wherein the image-forming unit forms, in response to the image-forming instruction, an image on a position of the surface, the position being corrected based on the correction amount.