PROBLEM TO BE SOLVED: To highlight a blood vessel pattern such as a surficial fine blood vessel and display a degree of haemoglobin oxygen saturation in the blood.SOLUTION: A subject is irradiated with oxygen saturation degree measurement light and blood vessel highlighting illumination light alternately and a reflected image thereof is captured by color imaging elements. A blue signal B1, a green signal G1 and a red signal R1 are obtained in irradiation with the oxygen saturation degree measurement light, whereas a blue signal B2, a green signal G2 and a red signal R2 are obtained in irradiation with the blood vessel highlighting illumination light. A degree of haemoglobin oxygen saturation in the blood is calculated from the blue signal B1, the green signal G2 and the red signal R2. The blue signal B2 with a signal value varied according to a degree of oxygen saturation is allocated to a B channel of a display device, the green signal G2 is allocated to a G channel of the display device and the red signal G2 is allocated to an R channel of the display device. Therefore, a surficial blood vessel and a middle/deep blood vessel are highlighted and the display device also displays an image containing a degree of oxygen saturation and highlighted blood vessels in which colors of the surficial blood vessel and the middle/deep blood vessel are varied according to a degree of oxygen saturation.COPYRIGHT: (C)2014,JPO&INPIT【課題】表層微細血管などの血管パターンを強調表示するとともに、血中ヘモグロビンの酸素飽和度を表示する。【解決手段】酸素飽和度測定光と血管強調用照明光を交互に検体に照射し、その反射像をカラーの撮像素子で撮像する。酸素飽和度測定光の照射時には青色信号B1、緑色信号G1、赤色信号R1が得られ、血管強調用照明光の照射時には青色信号B2、緑色信号G2、赤色信号R2得られる。青色信号B1、緑色信号G2、赤色信号R2から血中ヘモグロビンの酸素飽和度を算出する。酸素飽和度に応じて信号値を変化させた青色信号B2を表示装置のBチャンネルに、緑色信号G2を表示装置のGチャンネルに、赤色信号G2を表示装置のRチャンネルに割り当てる。これにより、表層血管及び中深層血管が強調表示され、また、それら表層血管及び中深層血管の色が、酸素飽和度に応じて変化する酸素飽和度+血管強調画像が表示装置に表示される。【選択図】図21B
