An endoscope includes an endoscope body carrying a display device and buttons, a display control circuit, a flexible tube member, an image pickup module, and a stop pin, which has a proximal end thereof connected to the composite of the flexible tube member and the image pickup module and a distal end thereof extending out of the composite to a predetermined length. Further, the display control circuit includes a scale display procedure, which is adapted for displaying a scale on the display device and has sufficient accuracy for determining the size, area or angle of the target only when the distal end of the stop pin is stopped against the target. Thus, the stop pin can be used to establish a distance between the image pickup module and the target, enabling the scale to be used for determination of the size, area or angle of the target being displayed on the display device.
