Control device for imaging system, imaging system, and method for controlling imaging system
A control device for an imaging system includes a video signal acquisition unit, a photometric unit, and a luminance control unit. The video signal acquisition unit is configured to acquire a video signal obtained by taking an image of fluorescence radiated from a subject under excitation by an excitation light that is emitted onto the subject. The photometric unit is configured to acquire brightness of the fluorescence based only on a color-specific video signal of one color corresponding to the fluorescence, the color-specific video signal being included in the video signal. The luminance control unit is configured to adjust luminance of a fluorescent image formed from the video signal, based on the brightness of the fluorescence acquired by the photometric unit.
1. An imaging system comprising:
a light source device configured to emit a green light, a blue light, and a red light onto a subject in a normal light observation mode, and to emit the green light, the blue light, and excitation light based on near-infrared light onto the subject in an infrared light observation mode, wherein an output intensity of the excitation light is set higher than output intensities of the green light and the blue light;
an imaging device configured to capture an image of return light of illumination light emitted from the light source device, the return light returning from the subject; and
at least one processor configured to:
acquire a video signal of the image captured by the imaging device;
perform detection processing by determining a divided video signal for each color of red, green, and blue included in the image captured by the imaging device, and (i) multiplying each divided video signal by a respective first predetermined parameter set for each color based on the mode of the light source device, the predetermined parameters forming a first specific ratio of the normal light observation mode, and (ii) multiplying each of the divided video signals of the captured image for each color by a respective second predetermined parameter set for each color forming a second specific ratio, which is different from the first specific ratio, of the infrared light observation mode;
calculate luminance based on a red image signal, a green image signal, and a blue image signal that have been subjected to the detection processing in the normal light observation mode, and calculate luminance based on a video signal that includes information of the red image signal only that has been subjected to the detection processing in the infrared light observation mode; and
adjust an electronic shutter of the imaging device so as to form an image for each field based on the calculated luminance in the normal light observation mode, and set multi-exposure settings for the imaging device so as to form an image for a plurality of fields based on the calculated luminance in the infrared light observation mode.
2. The imaging system according to claim 1 , wherein the processor is configured to set settings for gain adjustment of the video signal that has been subjected to the detection processing, based on the calculated luminance.
3. The imaging system according to claim 1 , wherein the processor is configured to set settings for outputs of the light source device based on the calculated luminance.