Electronic endoscope system having variable power function

The electronic endoscope system having a variable power function comprising:

• an objective optical system for optically magnifying an image to be observed by using a variable power lens;
• an electronic variable power circuit for electronically magnifying an image obtained via an image pick-up element by signal processing;
• common variable power operating means for operating optical variable power and electronic variable power;
• switching point setting means for setting a depth of field at the switching time between optical variable power and electronic variable power at an arbitrary value;
• a control circuit which continuously operates optical variable power and electronic variable power based on the operation of said variable power operating means, and controls the switching between optical variable power and electronic variable power with said arbitrary value of a depth of field being a switching point;
• and
• wherein the control for switching between optical variable power and electronic variable power is carried out in a depth field preference mode by the arbitrary value of depth of field, and said field depth preference mode can be set separately from an ordinary mode in which after said variable power lens is moved to a Near end, electronic variable power is executed.

An electronic endoscope system having a variable power function, comprising:

• an objective optical system for optically magnifying an image to be observed by using a variable power lens;
• an electronic variable power circuit for electronically magnifying an image obtained via an image pick-up element by signal processing;
• common variable power operating means for operating optical variable power and electronic variable power;
• switching point setting means for setting a depth of field of view at an arbitrary value by setting an enlargement ratio at the switching time between optical variable power and electronic variable power at an arbitrary value;
• a control circuit which continuously operates optical variable power and electronic variable power based on the operation of said variable power operating means, and controls the switching between optical variable power and electronic variable power with said arbitrary value of enlargement ratio being a switching point;
• and
• wherein said switching point setting means sets the depth of field at an arbitrary value by an operating member on an operating section.

The electronic endoscope system having a variable power function comprising:

• an objective optical system for optically magnifying an image to be observed by using a variable power lens;
• an electronic variable power circuit for electronically magnifying an image obtained via an image pick-up element by signal processing;
• common variable power operating means for operating optical variable power and electronic variable power;
• switching point setting means for setting an enlargement ratio at the switching time between optical variable power and electronic variable power at an arbitrary value;
• a control circuit which continuously operates optical variable power and electronic variable power based on the operation of said variable power operating means, and controls the switching between optical variable power and electronic variable power with said arbitrary setting value of enlargement ratio being a switching point;
• and
• wherein the control for switching between optical variable power and electronic variable power is carried out in a depth field preference mode by the arbitrary value of enlargement ratio, and said field depth preference mode can be set separately from an ordinary mode in which after said variable power lens is moved to the Near end, electronic variable power is executed.