Imaging apparatus

1. An imaging apparatus comprising:

a pupil division optical system including a first pupil transmitting light of a first wavelength band and a second pupil transmitting light of a second wavelength band different from the first wavelength band, an amount of components of a transmission wavelength band of first transmittance characteristics overlapping the first wavelength band being more than an amount of components of a transmission wavelength band of the first transmittance characteristics overlapping the second wavelength band, an amount of components of a transmission wavelength band of second transmittance characteristics overlapping the first wavelength band being more than an amount of components of a transmission wavelength band of the second transmittance characteristics overlapping the second wavelength band, an amount of components of a transmission wavelength band of third transmittance characteristics overlapping the second wavelength band being more than an amount of components of a transmission wavelength band of the third transmittance characteristics overlapping the first wavelength band, the first transmittance characteristics, the second transmittance characteristics, and the third transmittance characteristics being different from each other;

an imaging sensor configured to:

generate a first signal by capturing an image of light transmitted through the pupil division optical system and a first color filter having the first transmittance characteristics;

generate a second signal by capturing an image of light transmitted through the pupil division optical system and a second color filter having the second transmittance characteristics; and

generate a third signal by capturing an image of light transmitted through the pupil division optical system and a third color filter having the third transmittance characteristics; and

a processor comprising hardware, the processor being configured to:

generate a color image including the first signal as a first channel and the second signal as a second channel and a third channel;

calculate a first coefficient on the basis of the second signal and the third signal;

generate a fourth signal by correcting, on the basis of the calculated first coefficient, the second signal used for the third channel;

generate the color image including the first signal as the first channel, the second signal as the second channel, and the fourth signal as the third channel; and

output the generated color image to a display.

2. An imaging apparatus comprising:

a pupil division optical system including a first pupil transmitting light of a first wavelength band and a second pupil transmitting light of a second wavelength band different from the first wavelength band, an amount of components of a transmission wavelength band of first transmittance characteristics overlapping the first wavelength band being more than an amount of components of a transmission wavelength band of the first transmittance characteristics overlapping the second wavelength band, an amount of components of a transmission wavelength band of second transmittance characteristics overlapping the first wavelength band being more than an amount of components of a transmission wavelength band of the second transmittance characteristics overlapping the second wavelength band, an amount of components of a transmission wavelength band of third transmittance characteristics overlapping the second wavelength band being more than an amount of components of a transmission wavelength band of the third transmittance characteristics overlapping the first wavelength band, the first transmittance characteristics, the second transmittance characteristics, and the third transmittance characteristics being different from each other;

an imaging sensor configured to:

generate a first signal by capturing an image of light transmitted through the pupil division optical system and a first color filter having the first transmittance characteristics;

generate a second signal by capturing an image of light transmitted through the pupil division optical system and a second color filter having the second transmittance characteristics; and

generate a third signal by capturing an image of light transmitted through the pupil division optical system and a third color filter having the third transmittance characteristics;

a processor comprising hardware, the processor being configured to generate a color image including the first signal as a first channel and the second signal as a second channel and a third channel and configured to output the generated color image to a display; and

a light emitting device configured to generate illumination light having a first peak of an amount of light in the first wavelength band and having a second peak of an amount of light in the second wavelength band.

3. The imaging apparatus according to claim 2 , wherein

the first wavelength band includes longer wavelengths than any wavelength included in the second wavelength band,

an amount of the illumination light at the shortest wavelength of the first wavelength band is less than the amount of the illumination light at the first peak, and

an amount of the illumination light at the longest wavelength of the second wavelength band is less than the amount of the illumination light at the second peak.

4. The imaging apparatus according to claim 2 , wherein the processor is configured to correct at least one of the second signal and the third signal on the basis of an amount of components of illumination light, the second transmittance characteristics, and the third transmittance characteristics.

5. The imaging apparatus according to claim 4 , wherein the processor is configured to:

calculate a second coefficient on the basis of the amount of the components of the illumination light, the second transmittance characteristics, and the third transmittance characteristics;

multiply the third signal by the calculated second coefficient; and

subtract the third signal multiplied by the second coefficient from the second signal.

6. The imaging apparatus according to claim 4 , wherein the processor is configured to:

calculate a third coefficient on the basis of the amount of the components of the illumination light, the second transmittance characteristics, and the third transmittance characteristics;

multiply the second signal by the calculated third coefficient; and

subtract the second signal multiplied by the third coefficient from the third signal.

7. The imaging apparatus according to claim 2 , wherein the processor is configured to:

switch between a first state in which the light emitting device generates the illumination light used for measurement and a second state in which the light emitting device generates the illumination light used for observation, and

calculate at least one of a phase difference between the first signal and the third signal and a phase difference between the second signal and the third signal when the light emitting device is in the first state.