Blur detection device, imaging device, lens device, imaging device main body, blur detection method, and blur detection program

A blur detection device comprising:

• an angular velocity detector that detects an angular velocity of an imaging device;
• a posture detector that detects a posture of the imaging device with respect to an Earth's rotation axis;
• a rotation angular velocity component calculator that calculates an Earth's rotation angular velocity component superimposed on an output of the angular velocity detector based on the posture of the imaging device detected by the posture detector;
• a subtractor that subtracts the rotation angular velocity component calculated by the rotation angular velocity component calculator from the output of the angular velocity detector;
• a blur amount calculator that calculates a blur amount of the imaging device based on an output of the subtractor;
• a first high pass filter that performs high pass filter processing on the output of the subtractor, a cutoff frequency of the first high pass filter being set to be a value higher than a frequency of blurring caused by Earth's rotation;
• a second high pass filter that performs high pass filter processing on the output of the subtractor, a cutoff frequency of the second high pass filter being set to be a value lower than the frequency of the blurring caused by the Earth's rotation;
• and
• a switcher that switches an output destination of the subtractor to the first high pass filter or the second high pass filter based on an imaging condition.

A blur detection device comprising:

• an angular velocity detector that detects an angular velocity of an imaging device;
• a posture detector that detects a posture of the imaging device with respect to an Earth's rotation axis;
• a rotation angular velocity component calculator that calculates an Earth's rotation angular velocity component superimposed on an output of the angular velocity detector based on the posture of the imaging device detected by the posture detector;
• a subtractor that subtracts the rotation angular velocity component calculated by the rotation angular velocity component calculator from the output of the angular velocity detector;
• a blur amount calculator that calculates a blur amount of the imaging device based on an output of the subtractor;
• a first high pass filter that performs high pass filter processing on the output of the subtractor, a cutoff frequency of the first high pass filter being set to be a value higher than a frequency of blurring caused by Earth's rotation;
• a second high pass filter that performs high pass filter processing on the output of the subtractor, a cutoff frequency of the second high pass filter being set to be a value lower than the frequency of the blurring caused by the Earth's rotation;
• and
• a setter that sets an output destination of the subtractor to the first high pass filter or the second high pass filter.

A blur detection method comprising:

• a step of detecting an angular velocity of an imaging device;
• a step of detecting a posture of the imaging device with respect to an Earth's rotation axis;
• a step of calculating an Earth's rotation angular velocity component superimposed on a detection result of the angular velocity of the imaging device based on the detected posture of the imaging device;
• a step of subtracting the calculated rotation angular velocity component from the detection result of the angular velocity of the imaging device;
• a step of calculating a blur amount of the imaging device based on the subtracted detection result of the angular velocity of the imaging device;
• and
• a step of performing high pass filter processing on the subtracted detection result of the angular velocity of the imaging device, a cutoff frequency of the high pass filter processing being set to be a value lower than a frequency of blurring caused by Earth's rotation.

A non-transitory computer-readable recording medium causing a computer to execute:

• in a case where a command stored in the non-transitory computer-readable recording medium is read by the computer,
• a function of receiving an output from an angular velocity detector that detects an angular velocity of an imaging device;
• a function of receiving an output of a posture detector that detects a posture of the imaging device with respect to an Earth's rotation axis;
• a function of calculating an Earth's rotation angular velocity component superimposed on an output of the angular velocity detector based on the posture of the imaging device detected by the posture detector;
• a function of subtracting the calculated rotation angular velocity component from the output of the angular velocity detector;
• a function of calculating a blur amount of the imaging device based on the subtracted output of the angular velocity detector;
• and
• a function of performing high pass filter processing on the subtracted output of the angular velocity detector, a cutoff frequency of the high pass filter processing being set to be a value lower than a frequency of blurring caused by Earth's rotation.