Control device for actuator, lamp, and calibration method for same

A calibration method for a lamp including a lamp unit, an actuator capable of tilting the lamp unit such that an emission direction of light of the lamp unit is inclined in a vertical direction, a triaxial acceleration sensor that is tilted together with the lamp unit and outputs a signal related to a vector indicating a gravity direction, a memory that stores information related to a reference horizontal vector indicating a horizontal direction parallel to a vertical plane parallel to the emission direction in a coordinate system of the acceleration sensor in a first state where an orientation of the emission direction in the vertical direction is a predetermined direction, and a measurement unit that measures an inclination angle of the emission direction in the vertical plane based on the signal and the information related to the reference horizontal vector,

• the method comprising:
• a first arrangement step of placing the lamp in the first state;
• a first acquisition step of obtaining information related to a first vector indicating a gravity direction in the coordinate system of the acceleration sensor in the first state;
• a second arrangement step of bringing the lamp into a second state where the emission direction is inclined by a predetermined angle in the vertical plane from the first state;
• a second acquisition step of obtaining information related to a second vector indicating a gravity direction in the coordinate system of the acceleration sensor in the second state;
• a third acquisition step of obtaining information related to a third vector that is included in a plane including the first vector and the second vector and is perpendicular to the first vector;
• and
• a storage step of causing the memory to store the information related to the third vector as the information related to the reference horizontal vector.