Headlight controller

A headlight controller configured to control a headlight unit of a vehicle, the headlight unit including a low beam unit configured to emit a low beam and a high beam unit configured to emit a high beam and being configured to illuminate a predetermined range in front of the vehicle, the headlight controller comprising:

• an inter-vehicle distance obtainer configured to acquire an inter-vehicle distance between the vehicle and a vehicle in front of the vehicle;
• a light distribution controller configured to set, by an adaptive driving beam (ADB) control, a light distribution pattern that partially dims or shades, within an illumination range of the high beam unit, a range corresponding to a position of the front vehicle;
• an optical axis adjuster configured to adjust optical axes of the low beam unit and the high beam unit;
• and
• an illumination controller configured to, when the inter-vehicle distance is less than a first distance, control the optical axis adjuster to adjust downward by a predetermined amount at least the optical axis of the low beam unit so as to displace downward by the predetermined amount at least an illumination range of the low beam unit, independently of whether the light distribution controller is carrying out the ADB control.