| 摘要 |
In an optical endoscope having an image guide transmitting to the exit end surface an optical image formed by an objective optical system, a video signal of an imaging circuit built in an externally fitted camera is displayed by a displaying device so that, even in case the optical image range of the imaging surface is different, the displayed video signal may be of a proper brightness by a light adjusting element variably controlling the illuminating light amount fed to the optical endoscope on the basis of the output signals of a detector for detecting the optical image range on the imaging surface and a detector for detecting the level of the video signal. |
