Light deflection device

An light deflection device comprising:

• an light deflector having a mirror unit, a first piezoelectric actuator configured to cause the mirror unit to reciprocatingly turn around a first axis resonantly, and a second piezoelectric actuator configured to cause the mirror unit to reciprocatingly turn around a second axis non-resonantly, the second axis being in an intersecting relationship with the first axis;
• a drive unit configured to supply a first drive voltage and a second drive voltage to the first piezoelectric actuator and the second piezoelectric actuator, respectively, of the light deflector;
• a voltage fluctuation width detection unit configured to detect a second drive voltage fluctuation width;
• a swing angle fluctuation width detection unit configured to detect a first swing angle fluctuation width as a fluctuation width of a swing angle of the mirror unit around the first axis;
• a sensitivity equivalent value detection unit configured to detect a sensitivity equivalent value on the basis of a detected value of the second drive voltage fluctuation width and a detected value of the first swing angle fluctuation width, the sensitivity equivalent value being a ratio of the first swing angle fluctuation width to the second drive voltage fluctuation width;
• and
• a determination unit configured to determine whether a second axis side swing state of the mirror unit around the second axis is normal, on the basis of a detected value of the sensitivity equivalent value.