An endoscope includes: an insertion unit； an imaging unit to image a subject under examination and output an electrical image signal； a light modulation device to output an optical image signal based on the electrical image signal output from the imaging unit； a first light cable inserted in the insertion unit to transmit light emitted by a communication light source to the light modulation device； and a second light cable inserted in the insertion unit to transmit the optical image signal output from the light modulation device outside the insertion unit. The communication light source is different from an illumination light source emitting an illumination light for illuminating the subject under examination. The light modulation device modulates the light transmitted by the first light cable to generate the optical image signal.
