Patent ID: 8885031

Claim:
An endoscope system, comprising: a distal end portion which is inserted inside a specimen, and an external apparatus connected to the distal end portion, wherein the distal end portion has an imaging section that creates video signals, a video signal processing section that processes the video signals from the imaging section, a video transmitting section that transmits the processed video signals from the distal end portion to the external apparatus, a timing signal creation section that creates a timing signal that is needed to drive at least one of the imaging section, the video signal processing section, and the video transmitting section, and a base clock receiving section that receives a base clock, wherein the base clock is transmitted from the external apparatus to the distal end portion, wherein the base clock is received as an optical signal, wherein the timing signal is created from the base clock, and wherein the base clock receiving section converts the received optical signal into an electrical signal in the distal end portion, wherein the external apparatus has an insertion portion which guides the distal end portion into the specimen, a monitor that displays the video signals, a video processor that processes the video signals from the distal end portion and outputs them to the monitor, a base clock creation section that creates the base clock in the external apparatus, using a phase synchronization circuit that has a feedback mechanism, and a base clock transmitting section that converts the base clock into an optical signal and transmits the optical signal to the base clock receiving section, and wherein, in the endoscope system, the phase synchronization circuit is contained only within the external apparatus.