Endoscopic imaging system in which still image-specific or motion picture-specific expansion unit can be coupled to digital video output terminal in freely uncoupled manner

An endoscopic imaging system, comprising:

• an endoscope including an elongated insertion unit having a terminal portion.
• an illumination optical system located at the terminal portion of the elongated insertion unit for emitting illumination light,
• an objective optical system located at the terminal portion of said insertion unit for forming an optical image of an object illuminated with the illumination light, and
• an imaging device for photoelectrically converting the optical image either directly upon formation or after being transmitted through the insertion unit;
• a signal processing apparatus for driving said imaging device, processing an image signal output from said imaging device, producing a digital video signal and an analog video signal, and outputting the video signals through a digital video signal output terminal and analog video signal output terminal, respectively;
• a monitor for displaying an object image represented by the analog video signal in response to input of the analog video signal output through said analog video signal output terminal;
• a digital interface unit to be coupled to said digital video signal output terminal in a freely detachable manner, the digital interface unit including
• a memory in which said digital video signal is stored temporarily,
• a controller for controlling a read operation and a write operation to be performed relative to said memory, and
• a digital interface output unit for outputting the digital video signal upon being read from said memory in a form acceptable by an external device;
• and
• an external storage/recording device coupled to said digital video output terminal for storing or recording said digital video signal.