Electro Magnetic Compatibility Noise Free Endoscope Using Optical Fiber Communication Technology

Abstract

Recently, the number of pixels for an image sensor has exceeded more than 1 megapixel in the field of video endoscopes, while analog signal transmission bands that use existing electric wires will face physical limitations from the perspective of signal bandwidth and electro magnetic compatibility (EMC) noise. In order to solve these problems, we have developed a bi-directional digital optical communication endoscope system that employs both an image sensor and a single line optical fiber. In addition, due to the fiber's high-speed image signal transmission, we have incorporated a digital circuit for serial modulation and deserial demodulation. Consequently, we confirmed that transmission speeds of a 1 Gbps downlink image signal and a 110 kbps uplink control signal were achieved as a result of simultaneous communication. We also designed and tested a compact, co-axial bi-directional optical transmitter and receiver module that can be built into the distal side of a scope. The optical communication module size is less than φ4×10 mm2. It was confirmed that this module could be installed in the distal tip of a current endoscope.