US 12,436,380 B2
Optical scanning device and control method thereof
Takayuki Naono, Kanagawa (JP)
Assigned to FUJIFILM Corporation, Tokyo (JP)
Filed by FUJIFILM Corporation, Tokyo (JP)
Filed on Dec. 20, 2022, as Appl. No. 18/068,765.
Claims priority of application No. 2022-002608 (JP), filed on Jan. 11, 2022.
Prior Publication US 2023/0221546 A1, Jul. 13, 2023
Int. Cl. G02B 26/08 (2006.01); G02B 26/10 (2006.01)
CPC G02B 26/101 (2013.01) [G02B 26/0858 (2013.01)] 5 Claims
OG exemplary drawing
 
1. An optical scanning device comprising:
a mirror device that has a mirror portion, which is swingable around a first axis and a second axis orthogonal to each other, having a reflecting surface reflecting incident light, a first actuator causing the mirror portion to swing around the first axis by applying a rotational torque around the first axis to the mirror portion, and a second actuator causing the mirror portion to swing around the second axis by applying a rotational torque around the second axis to the mirror portion; and
a processor that provides a first driving signal to the first actuator and provides a second driving signal to the second actuator,
wherein the processor causes the mirror portion to perform a spiral rotation operation with the first driving signal and the second driving signal as cyclic voltage signals, and
in a case where a resonance frequency and a resonance Q value of a resonance mode, among resonance modes accompanied by mirror tilt swing around the first axis, closest to a frequency of the cyclic voltage signal are respectively set as fr1 and Q1, a resonance frequency and a resonance Q value of a resonance mode, among resonance modes accompanied by mirror tilt swing around the second axis, closest to the frequency of the cyclic voltage signal are respectively set as fr2 and Q2, and the frequency of the cyclic voltage signal is fd, a relationship of Q1≠Q2, fr2<fr1, and fr2×(1−1/(1.2×Q2))≤fd≤fr1×(1+1/(6×Q1)) is satisfied.