An optical device comprising optical and electronic variable magnification

An optical device with adjustable magnification with a mechanism for optically variable magnification with an adjustable lens (14), which is built in an objective optical system that is present at the front end of an endoscope to generate an optical manner a magnified image, and a circuit (30) for electronically adjustable magnification for electronic zoom detected by the objective optical system image, comprising: - a switch (21A, 21B) for adjustable magnification for changing the magnification by means of the mechanism for adjustable optical magnification and the mechanism for electronically adjustable magnification; and - a control circuit (20) for controlling the executed upon actuation of the switch for adjustable magnification operation for adjustable magnification to stop this operation temporarily when switching between optical and electronic variable magnification, while the switch is operated for adjustable magnification.