An improved image transmission path formed of individual optical fibers bundled together in side-by-side relation and which is capable of transmitting a high-contrast image is disclosed. Each fiber consists of a core having a higher refractive index and an encircling cladding having a lower refractive index. The improvement includes a means provided within or very close to the image transmission path by which the amount of the light falling on a single core and which is transmitted through that core and can be viewed at the receiving end is made not smaller than 10<2> times the amount of that light which is transmitted through the next adjacent core.
