Endoscope and endoscope cap with recessed focal point

摘要

A cap of an endoscope has an end part. On an inner periphery of the end part, a reference mark showing an ideal focus position and six marks are formed with regular intervals. When a circular end surface of the cap is pressed against a mucous membrane, the mucous membrane swells to the reference mark. Therefore, the mucous membrane can be kept at the ideal focus position for an object optical system.