US Patent 7907170 Electronic endoscope

An electronic endoscope has a light source that radiates illuminating light, a movie-image processor, a still-image processor, an image-change processor, and provisional image displayer. The still-image processor that alternately reads odd-line image-pixel signals and even-line image-pixel signals over two field interval to generate a still image on the basis of one frame worth of image-pixel signals generated by a one-time still image exposure. The illuminating light being blocked for a latter filed interval in the two field interval. The image change processor switches between a performance of the movie-image processor for displaying the movie-image and a performance of the still-image processor for displaying the still-image. While the still-image processor reads the odd-line and even-line image-pixel signals over the two field intervals, the provisional image displayer displays a provisional image on the basis of at least one of odd-field image-pixel signals and even-field image-pixel signals, which are obtained by an exposure before the still image exposure.