Method of controlling endoscope and endoscope

摘要

An endoscope 100 includes a first light source 45 that emits white illumination light, a second light source 47 that emits narrow-band light and an imaging section that has an imaging device 21 having plural detection pixels and images a region to be observed. The imaging section is caused to output a captured image signal including both a return light component of the white illumination light from the region to be observed by and a return light component of the narrow-band light the white illumination light. From the captured image signal, the return light component of the narrow-band light is selectively extracted, and a brightness level of the extracted return light component of the narrow-band light is changed by changing a light amount of light emitted from the second light source 47.

主权项

1. A method of controlling an endoscope comprising a first light source section that emits white illumination light, a second light source section that emits narrow-band light having a wavelength band narrower than that of the white illumination light, and an imaging section that captures a region to be observed by an imaging device comprising detection pixels of plural colors, the method comprising:
causing the imaging section to output a captured image signal including a return light component of the white illumination light from the region to be observed and a return light component of the narrow-band light from the region to be observed, wherein the captured image signal comprises a red image signal, a green image signal, and a blue image signal; generating captured images of red, green, and blue colors based on the red, green, and blue image signals, respectively, wherein the captured images include a first captured image, and of the captured images, the first captured image contains a most return light component of the narrow-band light emitted from the second light source; changing a brightness level of the first captured image relatively to brightness levels of captured images based on the red and green signals; dividing the first captured image and a second captured image which has a different reference color from that of the first captured image into common plural image areas; integrating brightness values in each image area of the first captured image to obtain an integrated brightness value of each image area of the first captured image; integrating brightness values in each image area of the second captured image to obtain an integrated brightness value of each image area of the second captured image; obtaining a ratio of the integrated brightness value of each image area of the first captured image and the integrated brightness value of the image area, having a same image positional relationship with each image area of the first captured image, of the second captured image; extracting image areas, of the first and second captured images, whose ratio is equal to or larger than a threshold value, as characteristic image areas; and selectively changing a brightness level of the characteristic image area of the first captured image.