Medical control device and medical observation system using a different wavelength band than that of fluorescence of an observation target to control focus or brightness

A medical control method comprising:

• determining whether an image sensor is operating in a first mode or a second mode;
• in response to the image sensor being in the first mode, acquiring a captured image of an observation target based on excitation light in a first wavelength band;
• in response to the image sensor being in the second mode, controlling an operation of a light source configured to simultaneously emit excitation light in the first wavelength band and light in a second wavelength band different from the first wavelength band;
• acquiring a captured image obtained by capturing an image of the observation target irradiated with light in the first wavelength band and in the second wavelength band emitted from the light source, wherein the observation target fluoresces in response to the excitation light to output light in a third wavelength band and reflects light in the second wavelength band to output light in the second wavelength band, the captured image including light components in the second and third wavelengths bands, the second and third wavelength bands being different;
• calculating, based on the captured image acquired while the observation target is irradiated with light in the first wavelength band and in the second wavelength band, an evaluation value used for at least one of a first control for controlling a focal position of the image sensor configured to generate the captured image or a second control for controlling a brightness of the captured image, wherein a component of the light in the second wavelength band is used for the calculation of the evaluation value;
• after calculating the evaluation value, removing the component of the light in the second wavelength band contained in the captured image;
• performing, based on the evaluation value, at least one of the first control or the second control;
• and
• outputting the captured image with the component of the light in the second wavelength band removed as an image to be displayed.

A non-transitory computer readable storage device having computer readable instructions that when executed by a processor cause the processor to:

• determine whether an image sensor to capture an image is operating in a first mode in which a fluorescent image of an observation target is to be captured at a predetermined frame rate and a second mode in which parameters of the image to be captured are controlled;
• in response to the image sensor being in the first mode,
• control an operation of a light source to emit excitation light in a first wavelength band,
• acquire a captured image of an observation target irradiated with light in the first wavelength band, wherein the observation target fluoresces in response to the excitation light to output light in a third wavelength band, and
• perform first image processing on the captured image of the observation target irradiated with the light in the first wavelength band which light in the third wavelength band;
• in response to the image sensor being in the second mode,
• control the operation of the light source to simultaneously emit excitation light in the first wavelength band and light in a second wavelength band different from the first wavelength band;
• acquire a captured image obtained by capturing an image of an observation target irradiated with light in the first wavelength band and in the second wavelength band emitted from the light source, wherein the observation target fluoresces in response to the excitation light to output light in a third wavelength band and reflects light in the second wavelength band to output light in the second wavelength band, the captured image including light components in the second and third wavelengths bands, the second and third wavelength bands being different;
• perform the first image processing on the captured image of light in the second and third wavelength bands;
• calculate, based on the captured image acquired while the observation target is irradiated with light in the first wavelength band and in the second wavelength band, an evaluation value used for at least one of a first control for controlling a focal position of the image sensor configured to generate the captured image or a second control for controlling a brightness of the captured image, wherein a component of the light in the second wavelength band is used for the calculation of the evaluation value;
• and
• perform, based on the evaluation value, at least one of the first control or the second control on the captured image of light in the second and third wavelength band subjected to the first image processing.