Image forming apparatus

An image forming apparatus including an optical unit including a light source and an optical system which focuses light emitted from the light source onto a photosensitive body, the apparatus comprising:

• a vibration adjustment unit which adjusts a natural frequency of the optical system;
• a measuring unit which measures vibrational information indicating change in vibration;
• a controller which independently drives each of units including a predetermined drive system;
• and
• a memory unit which stores a drive frequency of each of the units including the predetermined drive system,
• wherein the controller comprises:
• a first measurement control unit which controls the measuring unit to measure the vibrational information after the vibration adjustment unit adjusts the natural frequency of the optical system to a drive frequency of each unit, which is stored in the memory unit, at an initial state;
• an initial value memory control unit which stores the vibrational information measured through control of the first measurement control unit in the memory unit as initial vibrational information;
• a second measurement control unit which controls the measuring unit to measure the vibrational information after the vibration adjustment unit adjusts the natural frequency of the optical system to a drive frequency of a unit to be checked, which is stored in the memory unit;
• a comparing unit which compares the vibrational information measured through control of the second measurement control unit and the initial vibrational information measured after adjustment of the natural frequency of the optical system to the drive frequency of the unit to be checked among the stored initial vibrational information;
• and
• an abnormality determination unit which determines abnormality in the unit to be checked according to comparison made by the comparing unit.