US 12,007,556 B2
Light deflection device
Atsuhiko Chikaoka, Tokyo (JP)
Assigned to STANLEY ELECTRIC CO., LTD., Tokyo (JP)
Filed by STANLEY ELECTRIC CO., LTD., Tokyo (JP)
Filed on Apr. 9, 2021, as Appl. No. 17/226,242.
Claims priority of application No. 2020-076083 (JP), filed on Apr. 22, 2020.
Prior Publication US 2021/0333542 A1, Oct. 28, 2021
Int. Cl. G02B 26/10 (2006.01); B81B 3/00 (2006.01); B81B 7/00 (2006.01); B81B 7/02 (2006.01); G02B 26/08 (2006.01)
CPC G02B 26/101 (2013.01) [B81B 3/0021 (2013.01); B81B 3/0045 (2013.01); B81B 3/0062 (2013.01); B81B 7/008 (2013.01); B81B 7/02 (2013.01); G02B 26/0858 (2013.01); B81B 2201/042 (2013.01)] 8 Claims
OG exemplary drawing
 
1. 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.